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Kim SI, Chung TD. In Situ Real-Time Dendritic Growth Determination of Electrodeposits on Ultramicroelectrodes. Anal Chem 2024. [PMID: 38341845 DOI: 10.1021/acs.analchem.3c05239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2024]
Abstract
Monitoring the dendritic electrodeposition process is crucial in various fields such as energy storage devices and sensors. A variety of in situ dendritic growth monitoring methods have been developed, especially for battery applications, but they require specialized cells and equipment and are often invasive, making them unsuitable for various electrochemical systems and commercial batteries. To address these challenges, a real-time impedance analysis technique was used to determine dendritic electrodeposition on microelectrodes. The "effective size" of the electrodeposit was extracted from the impedance data, and the dendritic growth was assessed in real-time by comparing "effective size" to a theoretical radius assuming hemispherical growth. The technique was validated using scanning electron microscopy imaging and finite element method simulation. Initially applied to gold electrodeposition, the method was extended to zinc electrodeposition, demonstrating potential utilization for energy storage systems.
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Affiliation(s)
- Sung Il Kim
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
- Advanced Institutes of Convergence Technology, Suwon-Si, Gyeonggi-do 16229, South Korea
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2
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Cho W, Jung M, Yoon SH, Jeon J, Oh MA, Kim JY, Park M, Kang CM, Chung TD. On-Site Formation of Functional Dopaminergic Presynaptic Terminals on Neuroligin-2-Modified Gold-Coated Microspheres. ACS Appl Mater Interfaces 2024; 16:3082-3092. [PMID: 38206769 DOI: 10.1021/acsami.3c13829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Advancements in neural interface technologies have enabled the direct connection of neurons and electronics, facilitating chemical communication between neural systems and external devices. One promising approach is a synaptogenesis-involving method, which offers an opportunity for synaptic signaling between these systems. Janus synapses, one type of synaptic interface utilizing synaptic cell adhesion molecules for interface construction, possess unique features that enable the determination of location, direction of signal flow, and types of neurotransmitters involved, promoting directional and multifaceted communication. This study presents the first successful establishment of a Janus synapse between dopaminergic (DA) neurons and abiotic substrates by using a neuroligin-2 (NLG2)-mediated synapse-inducing method. NLG2 immobilized on gold-coated microspheres can induce synaptogenesis upon contact with spatially isolated DA axons. The induced DA Janus synapses exhibit stable synaptic activities comparable to that of native synapses over time, suggesting their suitability for application in neural interfaces. By calling for DA presynaptic organizations, the NLG2-immobilized abiotic substrate is a promising tool for the on-site detection of synaptic dopamine release.
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Affiliation(s)
- Wonkyung Cho
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Minji Jung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sun-Heui Yoon
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Joohee Jeon
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Min-Ah Oh
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji Yong Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Minjung Park
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Chung Mu Kang
- Advanced Institutes of Convergence Technology, Suwon-si 16229, Gyeonggi-do, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
- Advanced Institutes of Convergence Technology, Suwon-si 16229, Gyeonggi-do, Republic of Korea
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3
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Youn JH, Go SY, Chung H, Lee H, Chung TD, Cheong PHY, Lee HG. Dual Function of N-Iodosuccinimide for C(sp 3)-B Bond Activation. Org Lett 2024; 26:198-203. [PMID: 38153405 DOI: 10.1021/acs.orglett.3c03728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
A practical method for C(sp3)-B bond activation was developed. Using a combination of alkyl trifluoroborates and N-iodosuccinimide (NIS), various C(sp3)-heteroatom bonds were readily generated in an efficient manner. Mechanistic studies revealed the bifunctional ability of NIS: mediating the formation of reactive halogenated intermediates and activating them via halogen bonding. This electrophilic activation of the reaction center enables the utilization of general heteroatom nucleophiles, which are used in a limited capacity in traditional 1,2-metalate rearrangements.
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Affiliation(s)
- Ju Hyun Youn
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Su Yong Go
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyunho Chung
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Haeyeon Lee
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
- Advanced Institutes of Convergence Technology, Suwon-si, Gyeonggi-do 16229, Republic of Korea
| | - Paul Ha-Yeon Cheong
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
| | - Hong Geun Lee
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
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Tetteh EB, Krysiak OA, Savan A, Kim M, Zerdoumi R, Chung TD, Ludwig A, Schuhmann W. Long-Range SECCM Enables High-Throughput Electrochemical Screening of High Entropy Alloy Electrocatalysts at Up-To-Industrial Current Densities. Small Methods 2023:e2301284. [PMID: 38155148 DOI: 10.1002/smtd.202301284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/18/2023] [Indexed: 12/30/2023]
Abstract
High-entropy alloys (HEAs), especially in the form of compositional complex solid solutions (CCSS), have gained attention in the field of electrocatalysis. However, exploring their vast composition space concerning their electrocatalytic properties imposes significant challenges. Scanning electrochemical cell microscopy (SECCM) offers high-speed electrochemical analysis on surface areas with a lateral resolution down to tens of nm. However, high-precision piezo positioners often used for the motion of the tip limit the area of SECCM scans to the motion range of the piezo positioners which is typically a few tens of microns. To bridge this experimental gap, the study proposes a long-range SECCM system with a rapid gas-exchange environmental cell for high-throughput electrochemical characterization of 100 mm diameter HEA thin-film material libraries (ML) obtained by combinatorial co-sputtering. Due to the gas-liquid interface at the positioned SECCM droplet on the sample, high-throughput evaluation under industrial current density conditions becomes feasible. This allows the direct correlation between electrocatalytic activity and material composition with high statistical reliability. The multidimensional data obtained accelerates materials discovery, development, and optimization.
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Affiliation(s)
- Emmanuel Batsa Tetteh
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Olga A Krysiak
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Alan Savan
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Moonjoo Kim
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ridha Zerdoumi
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
- Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do, 16229, Republic of Korea
| | - Alfred Ludwig
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
- Center for Interface-Dominated High-Performance Materials, ZGH; Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Wolfgang Schuhmann
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
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Yoo H, Lee HR, Kang SB, Lee J, Park K, Yoo H, Kim J, Chung TD, Lee KM, Lim HH, Son CY, Sun JY, Oh SS. G-Quadruplex-Filtered Selective Ion-to-Ion Current Amplification for Non-Invasive Ion Monitoring in Real Time. Adv Mater 2023; 35:e2303655. [PMID: 37433455 DOI: 10.1002/adma.202303655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 07/08/2023] [Accepted: 07/10/2023] [Indexed: 07/13/2023]
Abstract
Living cells efflux intracellular ions for maintaining cellular life, so intravital measurements of specific ion signals are of significant importance for studying cellular functions and pharmacokinetics. In this work, de novo synthesis of artificial K+ -selective membrane and its integration with polyelectrolyte hydrogel-based open-junction ionic diode (OJID) is demonstrated, achieving a real-time K+ -selective ion-to-ion current amplification in complex bioenvironments. By mimicking biological K+ channels and nerve impulse transmitters, in-line K+ -binding G-quartets are introduced across freestanding lipid bilayers by G-specific hexylation of monolithic G-quadruplex, and the pre-filtered K+ flow is directly converted to amplified ionic currents by the OJID with a fast response time at 100 ms intervals. By the synergistic combination of charge repulsion, sieving, and ion recognition, the synthetic membrane allows K+ transport exclusively without water leakage; it is 250× and 17× more permeable toward K+ than monovalent anion, Cl- , and polyatomic cation, N-methyl-d-glucamine+ , respectively. The molecular recognition-mediated ion channeling provides a 500% larger signal for K+ as compared to Li+ (0.6× smaller than K+ ) despite the same valence. Using the miniaturized device, non-invasive, direct, and real-time K+ efflux monitoring from living cell spheroids is achieved with minimal crosstalk, specifically in identifying osmotic shock-induced necrosis and drug-antidote dynamics.
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Affiliation(s)
- Hyebin Yoo
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Hyun-Ro Lee
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Soon-Bo Kang
- Department of Materials Science & Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Juhwa Lee
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Kunwoong Park
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Hyunjae Yoo
- Department of Materials Science & Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Jinmin Kim
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, South Korea
| | - Kyung-Mi Lee
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul, 02841, South Korea
| | - Hyun-Ho Lim
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Chang Yun Son
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
- Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University, Incheon, 21983, South Korea
| | - Jeong-Yun Sun
- Department of Materials Science & Engineering, Seoul National University, Seoul, 08826, South Korea
- Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul, 08826, South Korea
| | - Seung Soo Oh
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
- Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University, Incheon, 21983, South Korea
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Kim JT, Lee CH, Jung D, Choi S, Jeong SH, Lee D, Lee Y, Chung TD. Virus-templated redox nanowire network for enzyme electrode. Biosens Bioelectron 2023; 237:115518. [PMID: 37442029 DOI: 10.1016/j.bios.2023.115518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/26/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023]
Abstract
Viruses have unique coat proteins that are genetically modifiable. Their surface can serve as a nano-template on which electroactive molecules are immobilized. In this study, we report filamentous bacteriophage as a backbone to which redox mediators are covalently and densely tethered, constructing redox nanowire, i.e. an electron conducting biomaterial. The highly ordered coat proteins of a filamentous bacteriophage provide flexible and biocompatible platform to constitute a biohybrid redox nanowire. Incorporating bacteriophage and redox molecules form an entangled assembly of nanowires enabling facile electron transfer. Electron transfer among the molecular mediators in the entangled assembly originates apparent electron diffusion of which the electron transfer rate is comparable to that observed in conventional redox polymers. Programming peptide terminals suggests further enhancement in electron mediation by increasing redox species mobility. In addition, the redox nanowire film functions as a favorable matrix for enzyme encapsulation. The stability of the enzymes entrapped in this unique matrix is substantially improved.
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Affiliation(s)
- Ji Tae Kim
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chang Heon Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Dongwook Jung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sejong Choi
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sung Hee Jeong
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea
| | - Dahye Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yan Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea; Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea; Electrochemistry Laboratory, Advanced Institutes of Convergence Technology, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea.
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Kim M, Batsa Tetteh E, Krysiak OA, Savan A, Xiao B, Piotrowiak TH, Andronescu C, Ludwig A, Dong Chung T, Schuhmann W. Acidic Hydrogen Evolution Electrocatalysis at High-Entropy Alloys Correlates with its Composition-Dependent Potential of Zero Charge. Angew Chem Int Ed Engl 2023; 62:e202310069. [PMID: 37537136 DOI: 10.1002/anie.202310069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/05/2023]
Abstract
The vast possibilities in the elemental combinations of high-entropy alloys (HEAs) make it essential to discover activity descriptors for establishing rational electrocatalyst design principles. Despite the increasing attention on the potential of zero charge (PZC) of hydrogen evolution reaction (HER) electrocatalyst, neither the PZC of HEAs nor the impact of the PZC on the HER activity at HEAs has been described. Here, we use scanning electrochemical cell microscopy (SECCM) to determine the PZC and the HER activities of various elemental compositions of a Pt-Pd-Ru-Ir-Ag thin-film HEA materials library (HEA-ML) with high statistical reliability. Interestingly, the PZC of Pt-Pd-Ru-Ir-Ag is linearly correlated with its composition-weighted average work function. The HER current density in acidic media positively correlates with the PZC, which can be explained by the preconcentration of H+ in the electrical double layer at potentials negative of the PZC.
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Affiliation(s)
- Moonjoo Kim
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Emmanuel Batsa Tetteh
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Olga A Krysiak
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Alan Savan
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
| | - Bin Xiao
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
| | - Tobias Horst Piotrowiak
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
| | - Corina Andronescu
- Technical Chemistry III and CENIDE Center for Nanointegration, Faculty of Chemistry, University of Duisburg-Essen, Carl-Benz-Straße 199, D-45141, Duisburg, Germany
| | - Alfred Ludwig
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
- ZGH, Ruhr, University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
- Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do 16229, Republic of Korea
| | - Wolfgang Schuhmann
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
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Cho W, Yoon SH, Chung TD. Streamlining the interface between electronics and neural systems for bidirectional electrochemical communication. Chem Sci 2023; 14:4463-4479. [PMID: 37152246 PMCID: PMC10155913 DOI: 10.1039/d3sc00338h] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 04/13/2023] [Indexed: 05/09/2023] Open
Abstract
Seamless neural interfaces conjoining neurons and electrochemical devices hold great potential for highly efficient signal transmission across neural systems and the external world. Signal transmission through chemical sensing and stimulation via electrochemistry is remarkable because communication occurs through the same chemical language of neurons. Emerging strategies based on synaptic interfaces, iontronics-based neuromodulation, and improvements in selective neurosensing techniques have been explored to achieve seamless integration and efficient neuro-electronics communication. Synaptic interfaces can directly exchange signals to and from neurons, in a similar manner to that of chemical synapses. Hydrogel-based iontronic chemical delivery devices are operationally compatible with neural systems for improved neuromodulation. In this perspective, we explore developments to improve the interface between neurons and electrodes by targeting neurons or sub-neuronal regions including synapses. Furthermore, recent progress in electrochemical neurosensing and iontronics-based chemical delivery is examined.
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Affiliation(s)
- Wonkyung Cho
- Department of Chemistry, Seoul National University Seoul 08826 Republic of Korea
| | - Sun-Heui Yoon
- Department of Chemistry, Seoul National University Seoul 08826 Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University Seoul 08826 Republic of Korea
- Advanced Institutes of Convergence Technology Suwon-si 16229 Gyeonggi-do Republic of Korea
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Kim M, Tetteh EB, Savan A, Xiao B, Ludwig A, Schuhmann W, Chung TD. Reorganization energy in a polybromide ionic liquid measured by scanning electrochemical cell microscopy. J Chem Phys 2023; 158:134707. [PMID: 37031154 DOI: 10.1063/5.0143018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
Room temperature ionic liquids (RT-ILs) are promising electrolytes for electrocatalysis. Understanding the effects of the electrode–electrolyte interface structure on electrocatalysis in RT-ILs is important. Ultrafast mass transport of redox species in N-methyl- N-ethyl-pyrrolidinium polybromide (MEPBr2n+1) enabled evaluation of the reorganization energy ( λ), which reflects the solvation structure in the inner Helmholtz plane (IHP). λ was achieved by fitting the electron transfer rate-limited voltammogram at a Pt ultramicroelectrode (UME) to the Marcus–Hush–Chidsey model for heterogeneous electron transfer kinetics. However, it is time-consuming or even impossible to prepare electrode materials, including alloys of numerous compositions in the form of UME, for each experiment. Herein, we report a method to evaluate the λ of MEPBr2n+1 by scanning electrochemical cell microscopy (SECCM), which allows high throughput electrochemical measurements using a single electrode with high spatial resolution. Fast mass transport in the nanosized SECCM tip is critical for achieving heterogeneous electron transfer-limited voltammograms. Furthermore, investigating λ on a high-entropy alloy materials library composed of Pt, Pd, Ru, Ir, and Ag suggests a negative correlation between λ and the work function. Given that the potential of zero charge correlates with the work function of electrodes, this can be attributed to the surface-charge sensitive ionic structure in the IHP of MEPBr2n+1, modulating the solvation energy of the redox-active species in the IHP.
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Affiliation(s)
- Moonjoo Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
- Analytical Chemistry – Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
| | - Emmanuel Batsa Tetteh
- Analytical Chemistry – Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
| | - Alan Savan
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
| | - Bin Xiao
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
| | - Alfred Ludwig
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
- ZGH, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
| | - Wolfgang Schuhmann
- Analytical Chemistry – Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstraße 150, Bochum, Germany
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
- Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do 16229, Republic of Korea
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Lee S, Lee H, Yeon SY, Chung TD. Enhanced adhesion of functional layers by controlled electrografting of ethylenediamine on ITO for electrochemical immunoassay in microfluidic channel. Biosens Bioelectron 2023; 229:115201. [PMID: 36947919 DOI: 10.1016/j.bios.2023.115201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/26/2023] [Accepted: 03/04/2023] [Indexed: 03/11/2023]
Abstract
Two-electrode (2E) system of the interdigitated electrode array (IDA), which operates neither reference nor counter electrodes, has great potential to miniaturize multiplex immunoassay in a microfluidic chip for point-of-care testing. However, it is necessary to firmly immobilize the mediator layer on IDA made of indium tin oxide (ITO) which is chemically inert. It is important because the mediator determines the electrochemical potential in the 2E system, but the layer is easy to be detached during the washing processes of immunoassay. Here, we controlled the concentration of ethylenediamine (EDA) to generate a permeable and robust film to adhere to mediators on the ITO IDA chip. Electrooxidation of EDA yielded thin oligomeric ethyleneimine (OEI) film and it provided amine groups for immobilizing the mediator, poly(toluidine blue) (pTB), via common conjugation reaction. Despite repeated flows in the microchannel, which are essential for sensitive immunoassay, the pTB/OEI layer was hardly washed and still remained on the ITO IDA. Myoglobin was measured down to ∼ pg/mL level. Therefore, the ITO IDA modified with the OEI film in the 2E system constituted a stable platform that withstands washing steps for sensitive electrochemical detection in the miniaturized immunoassay.
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Affiliation(s)
- Sunmi Lee
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea
| | - Haeyeon Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Song Yi Yeon
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Taek Dong Chung
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea; Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea; Advanced Institute of Convergence Technology, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea.
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Xu G, Xia X, Torresi RMM, Opallo M, Feliu JM, Chung TD. Editorial: Special Issue in Honour of Prof. Shaojun Dong’s 90th Birthday. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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12
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Lee J, Hwang DW, Cho W, Seo D, Won S, Chung TD. Anodic deposition of highly efficient nickel iron oxide electrocatalysts for water oxidation and role of anions in catalyst deposition. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Go SY, Chung H, Shin SJ, An S, Youn JH, Im TY, Kim JY, Chung TD, Lee HG. A Unified Synthetic Strategy to Introduce Heteroatoms via Electrochemical Functionalization of Alkyl Organoboron Reagents. J Am Chem Soc 2022; 144:9149-9160. [PMID: 35575552 DOI: 10.1021/jacs.2c03213] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Based on systematic electrochemical analysis, an integrated synthetic platform of C(sp3)-based organoboron compounds was established for the introduction of heteroatoms. The electrochemically mediated bond-forming strategy was shown to be highly effective for the functionalization of sp3-hybridized carbon atoms with significant steric hindrance. Moreover, virtually all the nonmetallic heteroatoms could be utilized as reaction partners using one unified protocol. The observed reactivity stems from the two consecutive single-electron oxidations of the substrate, which eventually generates an extremely reactive carbocation as the key intermediate. The detailed reaction profile could be elucidated through multifaceted electrochemical studies. Ultimately, a new dimension in the activation strategies for organoboron compounds was accomplished through the electrochemically driven reaction development.
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Affiliation(s)
- Su Yong Go
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Hyunho Chung
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Samuel Jaeho Shin
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Sohee An
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Ju Hyun Youn
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Tae Yeong Im
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Ji Yong Kim
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea.,Advanced Institutes of Convergence Technology, Suwon-si, Gyeonggi-do 16229 Republic of Korea
| | - Hong Geun Lee
- Department of Chemistry, College of Natural Science, Seoul National University, 1 Gwanak-ro, Seoul 08826, Republic of Korea
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14
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Yeon SY, Seo M, Kim Y, Hong H, Chung TD. Paper-based electrochromic glucose sensor with polyaniline on indium tin oxide nanoparticle layer as the optical readout. Biosens Bioelectron 2022; 203:114002. [DOI: 10.1016/j.bios.2022.114002] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/12/2022] [Accepted: 01/13/2022] [Indexed: 01/26/2023]
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15
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Yeon SY, Rho J, Kim Y, Chung TD. Reverse electrodialysis for emerging applications. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Song Yi Yeon
- Department of Chemistry Seoul National University Seoul Republic of Korea
| | - Jihun Rho
- Department of Chemistry Seoul National University Seoul Republic of Korea
| | - Yunju Kim
- Department of Chemistry Seoul National University Seoul Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry Seoul National University Seoul Republic of Korea
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16
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Seo D, Won S, Kim JT, Chung TD. Adopting Back Reduction Current as an Additional Output Signal for Achieving Photoelectrochemical Differentiated Detection. Anal Chem 2022; 94:2063-2071. [PMID: 35029970 DOI: 10.1021/acs.analchem.1c04129] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Photoelectrochemical (PEC) sensors are usually based on a single output signal, that is, the photocurrent change caused by the (photoelectro)chemical reaction between target analytes and photoelectrodes. However, the photocurrent may be influenced by redox species other than the target analyte; therefore, modifying the surface of photoelectrodes with probes that selectively bind to the analyte is essential. Moreover, even though various surface modification methods have been developed, distinguishing molecularly similar chemicals using PEC sensing systems remains a significant challenge. To address these selectivity issues, we proposed a photoanode-based PEC sensor that utilizes a cathodic transient current as a second output signal in addition to the photocurrent, which arises from the back reduction of photo-oxidized species. Factors influencing the back reduction were investigated by observing the transient photocurrent of hematite photoanodes in the presence of model redox probes. The chemical environment around the electrode-electrolyte interface was manipulated by altering the electrolyte composition or modifying the electrode surface. The favorable interaction between the electrode surface and redox species led to an increase in the extent of back reduction and the cathodic transient current. In addition, the extent of back reduction also depends on the chemical identity of the redox species, such as the kinetics of subsequent chemical reactions. Therefore, the synergistic combination of the photocurrent and the cathodic transient current enabled the differentiated detection of various catecholamine neurotransmitters with a single pristine photoelectrode, which has never been achieved using traditional PEC methods. Revisiting the transient photocurrent can complement conventional PEC applications and offers possibilities for more effective semiconductor-based applications.
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Affiliation(s)
- Daye Seo
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Sunghwan Won
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Ji Tae Kim
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea.,Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do 16229, Korea
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17
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Kim M, Park S, Chung TD. Heterogeneous electron transfer reorganization energy at the inner Helmholtz plane in a polybromide redox-active ionic liquid. Chem Sci 2022; 13:8821-8828. [PMID: 35975145 PMCID: PMC9350599 DOI: 10.1039/d2sc01410f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/30/2022] [Indexed: 11/21/2022] Open
Abstract
In ionic liquids (ILs), the electric double layer (EDL) is where heterogeneous electron transfer (ET) occurs. Nevertheless, the relationship between the EDL structure and its kinetics has been rarely studied, especially for ET taking place in the inner Helmholtz plane (IHP). This is largely because of the lack of an appropriate model system for experiments. In this work, we determined the reorganization energy (λ) of Br2 reduction in a redox-active IL 1-ethyl-1-methylpyrrolidinium polybromide (MEPBr2n+1) based on the Marcus–Hush–Chidsey model. Exceptionally fast mass transport of Br2 in MEPBr2n+1 allows voltammograms to be obtained in which the current plateau is regulated by electron-transfer kinetics. This enables investigation of the microscopic environment in the IHP of the IL affecting electrocatalytic reactions through reorganization energy. As a demonstration, TiO2-modified Pt was employed to show pH-dependent reorganization energy, which suggests the switch of major ions at the IHP as a function of surface charges of electrodes. Ultrafast transport of Br2 in a polybromide redox-active ionic liquid allows electron transfer-limited voltammograms of Br2 reduction. The reorganization energy at the inner-Helmholtz plane can be determined based on the Marcus–Hush–Chidsey model.![]()
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Affiliation(s)
- Moonjoo Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sangmee Park
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-si, Gyeonggi-do 16229, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-si, Gyeonggi-do 16229, Republic of Korea
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18
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Shin SJ, An S, Lee S, Lee JG, Chung TD. Direct electrodeposition of various metal nanocrystals on silicon oxide dielectric layer and insights into electrochemical behavior. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Samuel J. Shin
- Department of Chemistry Seoul National University Seoul South Korea
| | - Sohee An
- Department of Chemistry Seoul National University Seoul South Korea
| | - Sul Lee
- Advanced Institutes of Convergence Technology Suwon South Korea
| | - Jae Gyeong Lee
- Department of Chemistry Seoul National University Seoul South Korea
| | - Taek Dong Chung
- Department of Chemistry Seoul National University Seoul South Korea
- Advanced Institutes of Convergence Technology Suwon South Korea
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19
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Shin SJ, Chung TD. Electrochemistry of the Silicon Oxide Dielectric Layer: Principles, Electrochemical Reactions, and Perspectives. Chem Asian J 2021; 16:3014-3025. [PMID: 34402214 DOI: 10.1002/asia.202100798] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/11/2021] [Indexed: 01/26/2023]
Abstract
Electrochemistry of the silicon oxide dielectric layer, a notable insulator often used as a gate oxide, is counterintuitive, but addresses fundamental questions to yield novel scientific discoveries. In this minireview, the fundamental electron transfer mechanism of silicon oxide in the electrolyte solution is elucidated. The possible electrochemical reactions to date are discussed in detail, providing numerous potential areas of application which are elaborated and justified. This minireview not only provides background but also guides future research.
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Affiliation(s)
- Samuel J Shin
- Department of Chemistry, Seoul National University, Seoul, 08826, Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Korea.,Advanced Institutes of Convergence Technology, Suwon-si, Gyeonggi-do, 16229, Korea
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20
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Seo D, Kim JT, Hwang DW, Kim DY, Lim SY, Chung TD. Enhanced H 2 Evolution at Patterned MoS x-Modified Si-Based Photocathodes by Incorporating the Interfacial 3D Nanostructure of Ag. ACS Appl Mater Interfaces 2021; 13:46499-46506. [PMID: 34559532 DOI: 10.1021/acsami.1c08867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Photoelectrochemical cells represent one of the promising ways to renewably produce hydrogen (H2) as a future chemical fuel. The design of a catalyst/semiconductor junction for the hydrogen evolution reaction (HER) requires various factors for high performance. In catalytic materials, an intrinsic activity with fast charge-transfer kinetics is important. Additionally, their thermodynamic property and physical adhesion should be compatible with the underlying semiconductor for favorable band alignment and stability during vigorous H2 bubble formation. Moreover, catalysts, especially non-noble materials that demand a large amount of loading, should be adequately dispersed on the semiconductor surface to allow sufficient light absorption to generate excitons. One of the methods to simultaneously satisfy these conditions is to adopt an interfacial layer between the semiconductor and active materials in HER. The interfacial layer efficiently extracts the electrons from the semiconductor and conveys those to the catalytically active surface. We demonstrate Ag as a 3D interfacial nanostructure of patterned MoSx catalysts for photoelectrochemical HER. The nanostructured porous Ag layer was introduced by a simple chemical process, followed by photoelectrochemical deposition of MoSx to form MoSx/Ag nanostructures in cross-shaped catalyst pattern arrays. Ag modulated the surface electronic property of MoSx to improve the reaction kinetics as well as helped a charge transport at the Ag|p-Si(100) junction. The physically stable adhesion of catalysts was also achieved despite the ∼40 nm thick catalysts owing to the interfacial Ag nanostructure. This work contributes to further understand the complex multistep HER from light absorption to charge transfer to protons, helping to develop cost-effective and efficient photocathodes.
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Affiliation(s)
- Daye Seo
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Ji Tae Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Dae-Woong Hwang
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Da Yeon Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Sung Yul Lim
- Department of Chemistry and Research Institute for Basic Science, Kyung Hee University, Seoul 02447, Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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21
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Lim SY, Seo D, Jang MS, Chung TD. Functional Integration of Catalysts with Si Nanowire Photocathodes for Efficient Utilization of Photogenerated Charge Carriers. ACS Omega 2021; 6:22311-22316. [PMID: 34497920 PMCID: PMC8412901 DOI: 10.1021/acsomega.1c03014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Low-cost catalysts with high activity and durability are necessary to achieve efficient large-scale energy conversion in photoelectrochemical cell (PEC) systems. An additional factor that governs the construction of photoelectrodes for PECs is the spatial control of the catalysts for efficient utilization of photogenerated charge carriers. Here, we demonstrate spatial decoupling of the light-absorbing and catalytic components in hierarchically structured Si-based photocathodes for the hydrogen evolution reaction (HER). By simply modifying a well-known metal-assisted chemical etching procedure, we fabricated a Si nanowire (NW) array-based photocathode with Ag-Pt catalysts at the base and small amounts of the Pt catalyst at the NW tips. This approach simultaneously mitigates the parasitic light absorption by the catalytic layers and recombination of charge carriers owing to the long transport distance, resulting in improved photoelectrochemical HER performance under simulated AM 1.5G illumination.
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Affiliation(s)
- Sung Yul Lim
- Department
of Chemistry and Research Institute for Basic Science, Kyung Hee University, Seoul 02447, Korea
| | - Daye Seo
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Min Seok Jang
- School
of Electrical Engineering, Korea Advanced
Institute Science and Technology (KAIST), Daejeon 34141, Korea
| | - Taek Dong Chung
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
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22
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Lee J, Kim H, Park H, Kim T, Hwang SH, Seo D, Chung TD, Choi TL. Universal Suzuki-Miyaura Catalyst-Transfer Polymerization for Precision Synthesis of Strong Donor/Acceptor-Based Conjugated Polymers and Their Sequence Engineering. J Am Chem Soc 2021; 143:11180-11190. [PMID: 34264077 DOI: 10.1021/jacs.1c05080] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Catalyst-transfer polymerization has revolutionized the field of polymer synthesis due to its living character, but for a given catalyst system, the polymer scope is rather narrow. Herein we report a highly efficient Suzuki-Miyaura catalyst-transfer polymerization (SCTP) that covers a wide range of monomers from electron-rich (donor, D) to electron-deficient (acceptor, A) (hetero)arenes by rationally designing boronate monomers and using commercially available Buchwald RuPhos and SPhos Pd G3 precatalysts. Initially, we optimized the controlled polymerization of 3,4-propylenedioxythiophene (ProDOT), benzotriazole (BTz), quinoxaline (QX), and 2,3-diphenylquinoxaline (QXPh) by introducing new boronates, such as 4,4,8,8-tetramethyl-1,3,6,2-dioxazaborocane and its N-benzylated derivative, to modulate the reactivity and stability of the monomers. As a result, PProDOT, PBTz, PQX, and PQXPh were prepared with controlled molecular weight and narrow dispersity (Đ < 1.29) in excellent yield (>85%). A detailed investigation of the polymer structures using 1H NMR and MALDI-TOF spectrometry supported the chain-growth mechanism and the high initiation efficiency of the SCTP method. In addition, the use of RuPhos-Pd showing excellent catalyst-transfer ability on both D/A monomers led to unprecedented controlled D-A statistical copolymerization, thereby modulating the HOMO energy level (from -5.11 to -4.80 eV) and band gap energy (from 1.68 to 1.91 eV) of the resulting copolymers. Moreover, to demonstrate the living nature of SCTP, various combinations of D-A and A-A block copolymers (PBTz-b-PProDOT, PQX-b-PProDOT, and PQX-b-PBTz) were successfully prepared by the sequential addition method. Finally, simple but powerful one-shot D-A block copolymerization was achieved by maximizing the rate difference between a fast-propagating pinacol boronate donor and a slow-propagating acceptor to afford well-defined poly(3-hexylthiophene)-b-poly(benzotriazole).
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Affiliation(s)
- Jaeho Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Hwangseok Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyunwoo Park
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Taehyun Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Soon-Hyeok Hwang
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Daye Seo
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea.,Advanced Institutes of Convergence Technology, 16229 Suwon-Si, Gyeonggi-do, Republic of Korea
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
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23
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Lee CH, Seok H, Jang W, Kim JT, Park G, Kim HU, Rho J, Kim T, Chung TD. Bioaerosol monitoring by integrating DC impedance microfluidic cytometer with wet-cyclone air sampler. Biosens Bioelectron 2021; 192:113499. [PMID: 34311208 PMCID: PMC8275843 DOI: 10.1016/j.bios.2021.113499] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 06/27/2021] [Accepted: 07/08/2021] [Indexed: 12/17/2022]
Abstract
The recent outbreak of COVID-19 has highlighted the seriousness of airborne diseases and the need for a proper pathogen detection system. Compared to the ample amount of research on biological detection, work on integrated devices for air monitoring is rare. In this work, we integrated a wet-cyclone air sampler and a DC impedance microfluidic cytometer to build a cyclone-cytometer integrated air monitor (CCAM). The wet-cyclone air sampler sucks the air and concentrates the bioaerosols into 10 mL of aqueous solvent. After 5 min of air sampling, the bioaerosol-containing solution was conveyed to the microfluidic cytometer for detection. The device was tested with aerosolized microbeads, dust, and Escherichia coli (E. coli). CCAM is shown to differentiate particles from 0.96 to 2.95 μm with high accuracy. The wet cyclone air-sampler showed a 28.04% sampling efficiency, and the DC impedance cytometer showed 87.68% detection efficiency, giving a total of 24.59% overall CCAM efficiency. After validation of the device performance, CCAM was used to detect bacterial aerosols and their viability without any separate pretreatment step. Differentiation of dust, live E. coli, and dead E. coli was successfully performed by the addition of BacLight bacterial viability reagent in the sampling solvent. The usage could be further extended to detection of specific species with proper antibody fluorescent label. A promising strategy for aerosol detection is proposed through the constructive integration of a DC impedance microfluidic cytometer and a wet-cyclone air sampler.
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Affiliation(s)
- Chang Heon Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hyunho Seok
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Woohyuk Jang
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ji Tae Kim
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Geunsang Park
- School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hyeong-U Kim
- Plasma Engineering Laboratory, Korea Institute of Machinery and Materials, Daejeon, 32103, Republic of Korea
| | - Jihun Rho
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Taesung Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon, 16419, Republic of Korea; School of Mechanical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea.
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea.
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24
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Bang JJ, Han D, Shin J, Chung TD, Bae JH. Selective Enhancement of Electrochemical Signal Based on the Size of Alcohols Using Nanoporous Platinum. ChemElectroChem 2021. [DOI: 10.1002/celc.202100250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Jae Jin Bang
- Sakti3 Inc. Ann Arbor Michigan 48108 United States
| | - Donghoon Han
- Department of Chemistry The Catholic University of Korea Bucheon, Gyeonggi-do 14662 Republic of Korea
| | - Jinsik Shin
- Graduate School of Analytical Science and Technology Chungnam National University Daejeon 34134 Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry Seoul National University Seoul 08826 Republic of Korea
- Electrochemistry Laboratory Advanced Institutes of Convergence Technology Suwon, Gyeonggi-do 16229 Republic of Korea
| | - Je Hyun Bae
- Graduate School of Analytical Science and Technology Chungnam National University Daejeon 34134 Republic of Korea
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25
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Bang JJ, Han D, Shin J, Chung TD, Bae JH. Cover Feature: Selective Enhancement of Electrochemical Signal Based on the Size of Alcohols Using Nanoporous Platinum (ChemElectroChem 13/2021). ChemElectroChem 2021. [DOI: 10.1002/celc.202100691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jae Jin Bang
- Sakti3 Inc. Ann Arbor Michigan 48108 United States
| | - Donghoon Han
- Department of Chemistry The Catholic University of Korea Bucheon, Gyeonggi-do 14662 Republic of Korea
| | - Jinsik Shin
- Graduate School of Analytical Science and Technology Chungnam National University Daejeon 34134 Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry Seoul National University Seoul 08826 Republic of Korea
- Electrochemistry Laboratory Advanced Institutes of Convergence Technology Suwon, Gyeonggi-do 16229 Republic of Korea
| | - Je Hyun Bae
- Graduate School of Analytical Science and Technology Chungnam National University Daejeon 34134 Republic of Korea
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26
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Oh MA, Shin CI, Kim M, Kim J, Kang CM, Han SH, Sun JY, Oh SS, Kim YR, Chung TD. Inverted Ion Current Rectification-Based Chemical Delivery Probes for Stimulation of Neurons. ACS Appl Mater Interfaces 2021; 13:26748-26758. [PMID: 34078075 DOI: 10.1021/acsami.1c04949] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ion current rectification (ICR), diodelike behavior in surface-charged nanopores, shows promise in the design of delivery probes for manipulation of neural networks as it can solve diffusive leakages that might be critical in clinical and research applications. However, it has not been achieved because ICR has restrictions in nanosized dimension and low electrolyte concentration, and rectification direction is inappropriate for delivery. Herein, we present a polyelectrolyte gel-filled (PGF) micropipette harnessing inverted ICR as a delivery probe, which quantitatively transports glutamate to stimulate primary cultured neurons with high efficiency while minimizing leakages. Since the gel works as an ensemble of numerous surface-charged nanopores, the current is rectified in the micro-opening and physiological environment. By extending the charge-selective region using the gel, inverted ICR is generated, which drives outward deliveries of major charge carriers. This study will help in exploring new aspects of ICR and broaden its applications for advanced chemical delivery.
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Affiliation(s)
- Min-Ah Oh
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Chang Il Shin
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Moonjoo Kim
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Jayol Kim
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Chung Mu Kang
- Electrochemistry Laboratory, Advanced Institutes of Convergence Technology, 16229 Suwon-Si, Gyeonggi-do, Republic of Korea
| | - Seok Hee Han
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Jeong-Yun Sun
- Department of Materials Science & Engineering, Seoul National University, 08826 Seoul, Republic of Korea
- Research Institute of Advanced Materials, Seoul National University, 08826 Seoul, Republic of Korea
| | - Seung Soo Oh
- Department of Materials Science and Engineering, Pohang University of Science and Technology, 37673 Pohang, Gyeongbuk, South Korea
| | - Yang-Rae Kim
- Department of Chemistry, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
- Electrochemistry Laboratory, Advanced Institutes of Convergence Technology, 16229 Suwon-Si, Gyeonggi-do, Republic of Korea
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27
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Jeon J, Yoon SH, Oh MA, Cho W, Kim JY, Shin CI, Kim EJ, Chung TD. Neuroligin-1-Modified Electrodes for Specific Coupling with a Presynaptic Neuronal Membrane. ACS Appl Mater Interfaces 2021; 13:21944-21953. [PMID: 33909393 DOI: 10.1021/acsami.1c01298] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Coordination of synapses onto electrodes with high specificity and maintaining a stable and long-lasting interface have importance in the field of neural interfaces. One potential approach is to present ligands on the surface of electrodes that would be bound through a protein-protein interaction to specific areas of neuronal cells. Here, we functionalize electrode surfaces with genetically engineered neuroligin-1 protein and demonstrate the formation of a nascent presynaptic bouton upon binding to neurexin-1 β on the presynaptic membrane of neurons. The resulting synaptically connected electrode shows an assembly of presynaptic proteins and comparable exocytosis kinetics to that of native synapses. Importantly, a neuroligin-1-induced synapse-electrode interface exhibits type specificity and structural robustness. We envision that the use of synaptic adhesion proteins in modified neural electrodes may lead to new approaches in the interfacing of neural circuity and electronics.
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Affiliation(s)
- Joohee Jeon
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sun-Heui Yoon
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Min-Ah Oh
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Wonkyung Cho
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji Yong Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Chang Il Shin
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Eun Joong Kim
- Advanced Institute of Convergence Technology, Suwon-Si 16229, Gyeonggi-do, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
- Advanced Institute of Convergence Technology, Suwon-Si 16229, Gyeonggi-do, Republic of Korea
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28
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Affiliation(s)
- Je Hyun Bae
- Graduate School of Analytical Science and Technology Chungnam National University 34134 Daejeon Republic of Korea
| | - Kayeon Kim
- Helsinki Institute of Life Sciences Neuroscience Center University of Helsinki PO Box 63 FI-00271 Helsinki Finland
| | - Donghoon Han
- Department of Chemistry The Catholic University of Korea 14662 Bucheon Gyeonggi-do Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry Seoul National University 08826 Seoul Republic of Korea
- Electrochemistry Laboratory Advanced Institutes of Convergence Technology 16229 Suwon Gyeonggi-do Republic of Korea
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Han SH, Kim SI, Lee HR, Lim SM, Yeon SY, Oh MA, Lee S, Sun JY, Joo YC, Chung TD. Hydrogel-Based Iontronics on a Polydimethylsiloxane Microchip. ACS Appl Mater Interfaces 2021; 13:6606-6614. [PMID: 33496567 DOI: 10.1021/acsami.0c19892] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In response to the extensive utilization of ionic circuits, including in iontronics and wearable devices, a new method for fabricating a hydrogel-based ionic circuit on a polydimethylsiloxane (PDMS) microchip is reported. Prolonged UV/ozone oxidation combined with proper surface functionalizations and a novel microchip bonding method using thiol-epoxy click reaction enable the robust attachment of the photopolymerized hydrogel to the microchannel surface for eventual operation in electrolytes as an ionic circuit. The stretchable ionic diode constructed on the PDMS microchip shows a superior rectification ratio even under tensile stress and long-term storage stability. Furthermore, the combination of the ionic circuit and unique material properties of PDMS allows us to maximize the versatility and diversify the functionalities of the iontronic device, as demonstrated in a pressure-driven ionic switch and chip-integrated ionic regulator. Its iontronic signal transmission mimicking the excitatory and inhibitory synapses also evinces the potential of the hydrogel-based iontronics on the PDMS microchip as developed toward an aqueous neuromimetic information processor while opening up new opportunities for various bioinspired applications.
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Affiliation(s)
- Seok Hee Han
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Sung Il Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Hae-Ryung Lee
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
- Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 08826, Korea
| | - Seung-Min Lim
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
- Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 08826, Korea
| | - Song Yi Yeon
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Min-Ah Oh
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Sunmi Lee
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-si, Gyeonggi-do 16229, Korea
| | - Jeong-Yun Sun
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
- Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 08826, Korea
| | - Young-Chang Joo
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
- Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 08826, Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-si, Gyeonggi-do 16229, Korea
- Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do 16229, Korea
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30
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Lee D, Jeong SH, Yun S, Kim S, Sung J, Seo J, Son S, Kim JT, Susanti L, Jeong Y, Park S, Seo K, Kim SJ, Chung TD. Totally implantable enzymatic biofuel cell and brain stimulator operating in bird through wireless communication. Biosens Bioelectron 2020; 171:112746. [PMID: 33113388 DOI: 10.1016/j.bios.2020.112746] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/16/2020] [Accepted: 10/18/2020] [Indexed: 02/07/2023]
Abstract
Animals digest food to fuel brain neurometabolism via cellular respiration. This study demonstrates the combination of a biofuel cell (BFC) and an animal brain stimulator (ABS) implanted in a pigeon. Glucose oxidation and oxygen reduction in an enzymatic BFC supplied electrical power to the ABS. Power from the BFC reached 0.12 mW in vitro and 0.08 mW in vivo using only the natural glucose and oxygen in the pigeon's body. A power management integrated circuit is used to harvest energy from the in vivo BFC at a rate of 28.4 mJ over 10 min, which is sufficient for intermittent neurostimulation.
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Affiliation(s)
- Dahye Lee
- Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea
| | - Sung Hee Jeong
- Graduate School of Convergence Science and Technology, Seoul National University, 16229, Suwon-si, Gyeonggi-do, Republic of Korea
| | - Seunghyeon Yun
- Department of Electrical and Computer Engineering, Seoul National University, 08826, Seoul, Republic of Korea
| | - Sunhyo Kim
- Department of Veterinary Clinical Sciences, Seoul National University, 08826, Seoul, Republic of Korea
| | - Jaehoon Sung
- Department of Electrical and Computer Engineering, Seoul National University, 08826, Seoul, Republic of Korea; Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Jungmin Seo
- Department of Electrical and Computer Engineering, Seoul National University, 08826, Seoul, Republic of Korea
| | - Suyeon Son
- Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea
| | - Ji Tae Kim
- Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea
| | - Lina Susanti
- Department of Veterinary Clinical Sciences, Seoul National University, 08826, Seoul, Republic of Korea
| | - Youngseok Jeong
- Department of Veterinary Clinical Sciences, Seoul National University, 08826, Seoul, Republic of Korea
| | - Sanghyun Park
- Department of Veterinary Clinical Sciences, Seoul National University, 08826, Seoul, Republic of Korea
| | - Kangmoon Seo
- Department of Veterinary Clinical Sciences, Seoul National University, 08826, Seoul, Republic of Korea
| | - Sung June Kim
- Department of Electrical and Computer Engineering, Seoul National University, 08826, Seoul, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea; Graduate School of Convergence Science and Technology, Seoul National University, 16229, Suwon-si, Gyeonggi-do, Republic of Korea; Electrochemistry Laboratory, Advanced Institutes of Convergence Technology, 16229, Suwon-Si, Gyeonggi-do, Republic of Korea.
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31
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Yun J, Lee JG, Oh K, Kang K, Chung TD. Aqueous ionic effect on electrochemical breakdown of Si-dielectric-electrolyte interface. Sci Rep 2020; 10:16795. [PMID: 33033305 PMCID: PMC7544892 DOI: 10.1038/s41598-020-73880-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/17/2020] [Indexed: 11/10/2022] Open
Abstract
The breakdown of thin dielectric films (SiO2, Si3N4, HfO2) immersed in aqueous electrolyte was investigated. The current and the kinetics of dielectric breakdown caused by large cathodic electric field applied across the dielectric layer reveal the electrochemical nature of dielectric materials. Electrolytes play a huge role in the established dielectric-electrolyte interface with respect to the overall electrical behavior of the system. Although aqueous cations are considered as spectator ions in most electrochemical systems, in dielectric interfaces the current-potential characteristics depend on the type of cation. Computer simulation based on density functional theory and molecular dynamics showed cations affect the dielectric strength. The responses of various dielectric films to solution components provide invaluable information for dielectric-incorporated electrochemical systems.
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Affiliation(s)
- Jeongse Yun
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jae Gyeong Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kyungbae Oh
- Department of Materials Science and Engineering, Research Institute for Advanced Materials (RIAM), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Kisuk Kang
- Department of Materials Science and Engineering, Research Institute for Advanced Materials (RIAM), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
- Institute of Engineering Research, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea.
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32
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Lee Y, Yun J, Seo M, Kim SJ, Oh J, Kang CM, Sun HJ, Chung TD, Lee B. Full-Color-Tunable Nanophotonic Device Using Electrochromic Tungsten Trioxide Thin Film. Nano Lett 2020; 20:6084-6090. [PMID: 32603122 DOI: 10.1021/acs.nanolett.0c02097] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Color generation based on strategically designed plasmonic nanostructures is a promising approach for display applications with unprecedented high-resolution. However, it is disadvantageous in that the optical response is fixed once the structure is determined. Therefore, obtaining high modulation depth with reversible optical properties while maintaining its fixed nanostructure is a great challenge in nanophotonics. In this work, dynamic color tuning and switching using tungsten trioxide (WO3), a representative electrochromic material, are demonstrated with reflection-type and transmission-type optical devices. Thin WO3 films incorporated in simple stacked configurations undergo dynamic color change by the adjustment of their dielectric constant through the electrochromic principle. A large resonance wavelength shift up to 107 nm under an electrochemical bias of 3.2 V could be achieved by the reflection-type device. For the transmission-type device, on/off switchable color pixels with improved purity are demonstrated of which transmittance is modulated by up to 4.04:1.
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Affiliation(s)
- Yohan Lee
- Inter-University Semiconductor Research Center and School of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Jeongse Yun
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Minjee Seo
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Sun-Je Kim
- Inter-University Semiconductor Research Center and School of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
| | - Jaehyun Oh
- Department of Material Science and Engineering, Kunsan National University, Kunsan 54151, South Korea
| | - Chung Mu Kang
- Advanced Institute of Convergence Technology, Suwon 16229, South Korea
| | - Ho-Jung Sun
- Department of Material Science and Engineering, Kunsan National University, Kunsan 54151, South Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
- Advanced Institute of Convergence Technology, Suwon 16229, South Korea
| | - Byoungho Lee
- Inter-University Semiconductor Research Center and School of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea
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33
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Han SH, Rho J, Lee S, Kim M, Kim SI, Park S, Jang W, Lee CH, Chang BY, Chung TD. In Situ Real-Time Monitoring of ITO Film under a Chemical Etching Process Using Fourier Transform Electrochemical Impedance Spectroscopy. Anal Chem 2020; 92:10504-10511. [PMID: 32489093 DOI: 10.1021/acs.analchem.0c01294] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As a novel approach to the in situ real-time investigation of an ITO electrode during the wet etching process, step-excitation Fourier-transform electrochemical impedance spectroscopy (FT-EIS) was implemented. The equivalent circuit parameters (e.g., Rct, Cdl) continuously obtained by the FT-EIS measurements during the entire etching process showed an electrode activation at the initial period as well as the completion of etching. The FT-EIS results were further validated by cyclic voltammograms and impedance measurements of partially etched ITO films using ferri- and ferrocyanide solution in combination with FESEM imaging, EDS, XRD analyses, and COMSOL simulation. We also demonstrated that this technique can be further utilized to obtain intact interdigitated array (IDA) electrodes in a reproducible manner, which is generally considered to be quite tricky due to delicacy of the pattern. Given that the FT-EIS allows for instantaneous snapshots of the electrode at every moment, this work may hold promise for in situ real-time examination of structural, electrokinetic, or mass transfer-related information on electrochemical systems undergoing constantly changing, transient processes including etching, which would be impossible with conventional electroanalytical techniques.
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Affiliation(s)
- Seok Hee Han
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Jihun Rho
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Sunmi Lee
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do 16229, South Korea
| | - Moonjoo Kim
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Sung Il Kim
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Sangmee Park
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do 16229, South Korea
| | - Woohyuk Jang
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Chang Heon Lee
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - Byoung-Yong Chang
- Department of Chemistry, Pukyong University, Busan 48513, South Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea.,Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do 16229, South Korea.,Advanced Institute of Convergence Technology, Suwon-Si, Gyeonggi-do 16229, South Korea
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34
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Affiliation(s)
- Jihun Rho
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Song Yi Yeon
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
- Advanced Institutes of Convergence Technology, Suwon-Si, Gyeonggi-do 16229, Republic of Korea
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35
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Shin SJ, Koo JJ, Lee JK, Chung TD. Unique Luminescence of Hexagonal Dominant Colloidal Copper Indium Sulphide Quantum Dots in Dispersed Solutions. Sci Rep 2019; 9:20144. [PMID: 31882977 PMCID: PMC6934773 DOI: 10.1038/s41598-019-56762-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 11/14/2019] [Indexed: 12/04/2022] Open
Abstract
Luminescent hexagonal dominant copper indium sulphide (h-dominant CIS) quantum dots (QDs) by precursor-injection of mixed metal-dialkyldithiocarbamate precursors. Owing to the different reactivity of the precursors, this method allowed the CIS QDs to grow while retaining the crystallinity of the hexagonal nucleus. The photoluminescence (PL) spectra exhibited dual emission (600–700 nm red emission and 700–800 nm NIR emission) resulting from the combined contributions of the hexagonal (wurtzite) h-CIS and tetragonal (chalcopyrite) t-CIS QDs, i.e. the NIR and red emissions were due to the h-CIS QDs and coexisting t-CIS QDs (weight ratio of h-CIS/t-CIS ~ 10), respectively. The PL intensities of the h-CIS as well as t-CIS QDs were enhanced by post-synthetic heat treatment; the t-CIS QDs were particularly sensitive to the heat treatment. By separating h-CIS and t-CIS successfully, it was demonstrated that this phenomenon was not affected by size and composition but by the donor-acceptor pair states and defect concentration originating from their crystal structure. The h-dominant CIS QDs in this work provide a new technique to control the optical property of Cu-In-S ternary NCs.
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Affiliation(s)
- Samuel Jaeho Shin
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ja-Jung Koo
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jin-Kyu Lee
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul, 08826, Republic of Korea.,Technology Research Centre, LG Chem, Seoul, 07796, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, College of Natural Science, Seoul National University, Seoul, 08826, Republic of Korea. .,Advanced Institutes of Convergence Technology, Suwon-Si, Gyeonggi-do, 16229, Republic of Korea.
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36
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Lim SM, Yoo H, Oh MA, Han SH, Lee HR, Chung TD, Joo YC, Sun JY. Ion-to-ion amplification through an open-junction ionic diode. Proc Natl Acad Sci U S A 2019; 116:13807-13815. [PMID: 31221759 PMCID: PMC6628834 DOI: 10.1073/pnas.1903900116] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
As biological signals are mainly based on ion transport, the differences in signal carriers have become a major issue for the intimate communication between electrical devices and biological areas. In this respect, an ionic device which can directly interpret ionic signals from biological systems needs to be designed. Particularly, it is also required to amplify the ionic signals for effective signal processing, since the amount of ions acquired from biological systems is very small. Here, we report the signal amplification in ionic systems as well as sensing through the modified design of polyelectrolyte hydrogel-based ionic diodes. By designing an open-junction structure, ionic signals from the external environment can be directly transmitted to an ionic diode. Moreover, the minute ionic signals injected into the devices can also be amplified to a large amount of ions. The signal transduction mechanism of the ion-to-ion amplification is suggested and clearly verified by revealing the generation of breakdown ionic currents during an ion injection. Subsequently, various methods for enhancing the amplification are suggested.
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Affiliation(s)
- Seung-Min Lim
- Department of Materials Science & Engineering, Seoul National University, 08826 Seoul, Republic of Korea
| | - Hyunjae Yoo
- Department of Materials Science & Engineering, Seoul National University, 08826 Seoul, Republic of Korea
| | - Min-Ah Oh
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Seok Hee Han
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
| | - Hae-Ryung Lee
- Department of Materials Science & Engineering, Seoul National University, 08826 Seoul, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, 08826 Seoul, Republic of Korea
- Electrochemistry Laboratory, Advanced Institutes of Convergence Technology, 16229 Suwon-Si, Gyeonggi-do, Republic of Korea
| | - Young-Chang Joo
- Department of Materials Science & Engineering, Seoul National University, 08826 Seoul, Republic of Korea
- Research Institute of Advanced Materials, Seoul National University, 08826 Seoul, Republic of Korea
| | - Jeong-Yun Sun
- Department of Materials Science & Engineering, Seoul National University, 08826 Seoul, Republic of Korea;
- Research Institute of Advanced Materials, Seoul National University, 08826 Seoul, Republic of Korea
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37
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Jeon J, Oh MA, Cho W, Yoon SH, Kim JY, Chung TD. Robust Induced Presynapse on Artificial Substrates as a Neural Interfacing Method. ACS Appl Mater Interfaces 2019; 11:7764-7773. [PMID: 30707832 DOI: 10.1021/acsami.8b20405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Over the recent years, the development of neural interface systems has stuck to using electrical cues to stimulate neurons and read out neural signals, although neurons relay signals via chemical release and recognition at synapses. In addition, conventional neural interfaces are vulnerable to cell migration and glial encapsulation due to the absence of connection anchoring the neuron into the device unlike synapses, which are firmly sustained by protein bonding. To close this discrepancy, we conducted an intensive investigation into the induced synapse interface by employing engineered synaptic proteins from a neural interface perspective. The strong potential of induced synaptic differentiation as an emerging neural interfacing technique is demonstrated by exploring its structural features, chemical release kinetics, robustness, and scalability to the brain tissue. We show that the exocytosis kinetics of induced synapses is similar to that of endogenous synapses. Moreover, induced synapses show remarkable stability, despite cell migration and growth. The synapse-inducing technique has broad applications to cultured hippocampal and cortex tissues and suggests a promising method to integrate neural circuits with digital elements.
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Affiliation(s)
- Joohee Jeon
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Min-Ah Oh
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Wonkyung Cho
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Sun-Heui Yoon
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Ji Yong Kim
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
- Advanced Institutes of Convergence Technology , Suwon-Si , Gyeonggi-do 16229 , Republic of Korea
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38
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Lim SY, Ha K, Ha H, Lee SY, Jang MS, Choi M, Chung TD. Three-dimensionally patterned Ag–Pt alloy catalyst on planar Si photocathodes for photoelectrochemical H2 evolution. Phys Chem Chem Phys 2019; 21:4184-4192. [DOI: 10.1039/c8cp07304j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three-dimensionally patterned Ag–Pt alloy catalyst improves a junction quality of electrolyte/SiOx/Si photocathodes for H2 evolution.
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Affiliation(s)
- Sung Yul Lim
- Department of Chemistry
- Seoul National University
- Seoul 08826
- Korea
| | - Kyungyeon Ha
- Department of Mechanical and Aerospace Engineering
- Seoul National University
- Seoul 08826
- Korea
- Global Frontier Center for Multiscale Energy Systems
| | - Heonhak Ha
- School of Electrical Engineering
- Korea Advanced Institute Science and Technology (KAIST)
- Daejeon 34141
- Korea
| | - Soo Youn Lee
- Department of Chemistry
- Seoul National University
- Seoul 08826
- Korea
| | - Min Seok Jang
- School of Electrical Engineering
- Korea Advanced Institute Science and Technology (KAIST)
- Daejeon 34141
- Korea
| | - Mansoo Choi
- Department of Mechanical and Aerospace Engineering
- Seoul National University
- Seoul 08826
- Korea
- Global Frontier Center for Multiscale Energy Systems
| | - Taek Dong Chung
- Department of Chemistry
- Seoul National University
- Seoul 08826
- Korea
- Advanced Institutes of Convergence Technology (AICT)
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39
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Yeon SY, Yun J, Yoon SH, Lee D, Jang W, Han SH, Kang CM, Chung TD. A miniaturized solid salt reverse electrodialysis battery: a durable and fully ionic power source. Chem Sci 2018; 9:8071-8076. [PMID: 30542555 PMCID: PMC6238720 DOI: 10.1039/c8sc02954g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 08/27/2018] [Indexed: 01/07/2023] Open
Abstract
A novel pump-free miniaturized reverse electrodialysis (RED) system was designed to provide lasting power transduced from salinity gradients, named solid salt RED (ssRED), and this quasi-battery uses a solid salt instead of electrolyte solution for streamlined usage. It is portable, flexible, comparable in size to a universal serial bus flash drive, and easily activated with a small amount of water. It maintains a constant ionic concentration gradient through precipitation reactions between a pair of different salts. This precipitation-assisted solid salt RED (PssRED) is an unprecedented ionic power source as it can generate steady electricity in the absence of a driving pump. The PssRED was successfully coupled with bipolar electrode (BPE) microchip sensors which require stable ionic electricity and a polyelectrolyte ionic diode to realize a fully ionic circuit. It is envisioned that the range of application could be expanded to supply electromotive force to various devices through an ionic charge flow.
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Affiliation(s)
- Song Yi Yeon
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
| | - Jeongse Yun
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
| | - Sun-Heui Yoon
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
| | - Dahye Lee
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
| | - Woohyuk Jang
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
| | - Seok Hee Han
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
| | - Chung Mu Kang
- Advanced Institute of Convergence Technology , Suwon-si , Gyeonggi-do 16229 , Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry , Seoul National University , Seoul , 08826 , Republic of Korea .
- Advanced Institute of Convergence Technology , Suwon-si , Gyeonggi-do 16229 , Republic of Korea
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40
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Seo D, Lim SY, Lee J, Yun J, Chung TD. Robust and High Spatial Resolution Light Addressable Electrochemistry Using Hematite (α-Fe 2O 3) Photoanodes. ACS Appl Mater Interfaces 2018; 10:33662-33668. [PMID: 30230316 DOI: 10.1021/acsami.8b10812] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Light addressable/activated electrochemistry (LAE) has recently attracted attention as it can provide spatially resolved electrochemical information without using pre-patterned electrodes whose sizes and positions are unchangeable. Here, we propose hematite (α-Fe2O3) as the photoanode for LAE, which does not require any sort of surface modification for protection or facilitating charge transfer. As experimentally confirmed with various redox species, hematite is stable enough to be used for repetitive electroanalytical measurements. More importantly, it offers exceptionally high spatial resolution so that the "virtual electrode" is exactly as large as the light spot owing to the short diffusion length of the minority carriers. Quantitative analysis of dopamine in this study shows that the hematite-based photoanode is a promising platform for many potential LAE applications including spatially selective detection of oxidizable biomolecules.
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Affiliation(s)
- Daye Seo
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Sung Yul Lim
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Jihye Lee
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Jeongse Yun
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Taek Dong Chung
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
- Advanced Institutes of Convergence Technology , Suwon-si , Gyeonggi-do 16229 , Korea
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41
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Baek S, Kwon SR, Yeon SY, Yoon SH, Kang CM, Han SH, Lee D, Chung TD. Miniaturized Reverse Electrodialysis-Powered Biosensor Using Electrochemiluminescence on Bipolar Electrode. Anal Chem 2018. [PMID: 29521095 DOI: 10.1021/acs.analchem.7b05425] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We suggest an electrochemiluminescence (ECL)-sensing platform driven by ecofriendly, disposable, and miniaturized reverse electrodialysis (RED) patches as an electric power source. The flexible RED patches composed of ion-exchange membranes (IEMs) can produce voltage required for ECL sensing by simply choosing the appropriate number of IEMs and the ratio of salt concentrations. We integrate the RED patch with a bipolar electrode on the microfluidic chip to demonstrate the proof-of-concept, i.e., glucose detection in the range of 0.5-10 mM by observing ECL emissions with naked eyes. The miniaturized RED-powered biosensing system is widely applicable for electrochemical-sensing platforms. This is expected to be a solution for practical availability of battery-free electrochemical sensors for disease diagnosis in developing countries.
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Affiliation(s)
- Seol Baek
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Seung-Ryong Kwon
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Song Yi Yeon
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Sun-Heui Yoon
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Chung Mu Kang
- Advanced Institutes of Convergence Technology , Suwon-Si , Gyeonggi-do 16229 , Korea
| | - Seok Hee Han
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Dahye Lee
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea
| | - Taek Dong Chung
- Department of Chemistry , Seoul National University , Seoul 08826 , Korea.,Advanced Institutes of Convergence Technology , Suwon-Si , Gyeonggi-do 16229 , Korea
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42
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Lee D, Lee S, Rho J, Jang W, Han SH, Chung TD. 3D interdigitated electrode array in the microchannel free of reference and counter electrodes. Biosens Bioelectron 2018; 101:317-321. [DOI: 10.1016/j.bios.2017.09.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 09/22/2017] [Accepted: 09/27/2017] [Indexed: 01/05/2023]
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43
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Yun J, Cho YB, Jang W, Lee JG, Shin SJ, Han SH, Lee Y, Chung TD. Dielectric Breakdown and Post-Breakdown Dissolution of Si/SiO 2 Cathodes in Acidic Aqueous Electrochemical Environment. Sci Rep 2018; 8:1911. [PMID: 29382915 PMCID: PMC5789982 DOI: 10.1038/s41598-018-20247-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/10/2018] [Indexed: 11/17/2022] Open
Abstract
Understanding the conducting mechanisms of dielectric materials under various conditions is of increasing importance. Here, we report the dielectric breakdown (DB) and post-breakdown mechanism of Si/SiO2, a widely used semiconductor and dielectric, in an acidic aqueous electrochemical environment. Cathodic breakdown was found to generate conduction spots on the Si/SiO2 surface. Using scanning electrochemical microscopy (SECM), the size and number of conduction spots are confirmed to increase from nanometer to micrometer scale during the application of negative voltage. The morphologies of these conduction spots reveal locally recessed inverted-pyramidal structures with exposed Si{111} sidewalls. The pits generation preceded by DB is considered to occur via cathodic dissolution of Si and exfoliation of SiO2 that are induced by local pH increases due to the hydrogen evolution reaction (HER) at the conduction spots. The HER at the conduction spots is more sluggish due to strongly hydrogen-terminated Si{111} surfaces.
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Affiliation(s)
- Jeongse Yun
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yun-Bin Cho
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Woohyuk Jang
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jae Gyeong Lee
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Samuel Jaeho Shin
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seok Hee Han
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Youngmi Lee
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 03760, Republic of Korea.
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea. .,Advanced Institutes of Convergence Technology, Suwon-si, Gyeonggi-do, 16229, Republic of Korea.
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44
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45
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Affiliation(s)
- Jihun Rho
- Department of Chemistry; Seoul National University; 1 Gwanak-ro, Gwanak-gu Seoul 08826 Korea
| | - Sung Yul Lim
- Department of Chemistry; Seoul National University; 1 Gwanak-ro, Gwanak-gu Seoul 08826 Korea
| | - Inseong Hwang
- Department of Chemistry; Seoul National University; 1 Gwanak-ro, Gwanak-gu Seoul 08826 Korea
| | - Jeongse Yun
- Department of Chemistry; Seoul National University; 1 Gwanak-ro, Gwanak-gu Seoul 08826 Korea
| | - Taek Dong Chung
- Department of Chemistry; Seoul National University; 1 Gwanak-ro, Gwanak-gu Seoul 08826 Korea
- Advanced Institutes of Convergence Technology; Suwon-Si Gyeonggi-do 16229 Korea
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46
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Rho J, Jang W, Hwang I, Lee D, Lee CH, Chung TD. Multiplex immunoassays using virus-tethered gold microspheres by DC impedance-based flow cytometry. Biosens Bioelectron 2017; 102:121-128. [PMID: 29128714 DOI: 10.1016/j.bios.2017.11.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/31/2017] [Accepted: 11/06/2017] [Indexed: 11/17/2022]
Abstract
Bead-based multiplex immunoassays for common use require enhanced sensitivity and effective prevention of non-specific adsorption, as well as miniaturization of the detection device. In this work, we have implemented virus-tethered gold microspheres for multiplex immunoassay applications, employing a DC impedance-based flow cytometer as a detection element. The advantages of virus-tethered gold microspheres, including excellent prevention of non-specific adsorption, are extended to signal enhancement arising from the large quantity of antibody loading on each virion, and to flexible movement of filamentous virus. Individual virus-tethered beads generate their own DC impedance and fluorescence signals, which are simultaneously detected by a chip-based microfluidic flow cytometer. This system successfully realized multiplex immunoassays involving four biomarkers: cardiac troponin I (cTnI), prostate specific antigen (PSA), creatine kinase MB (CK-MB), and myoglobin in undiluted human sera, elevating sensitivity by up to 5.7-fold compared to the beads without virus. Constructive integration between filamentous virus-tethered Au-layered microspheres and use of a microfluidic cytometer suggests a promising strategy for competitive multiplex immunoassay development based on suspension arrays.
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Affiliation(s)
- Jihun Rho
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Woohyuk Jang
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Inseong Hwang
- InSol Co., Ltd., Yangjae-daero 85-gil, Gangdong-gu, Seoul 05408, Republic of Korea
| | - Dahye Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Chang Heon Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea; Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-Si, Gyeonggi-do 16229, Republic of Korea; Advanced Institutes of Convergence Technology, Suwon-Si, Gyeonggi-do 16229, Republic of Korea.
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47
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Han DH, Park S, Kim EJ, Chung TD. In situ Confocal Microscopy of Electrochemical Generation and Collision of Emulsion Droplets in Bromide Redox System. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.08.132] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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48
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Lee JG, Lee JY, Yun J, Lee Y, Lee S, Shin SJ, Bae JH, Chung TD. Conduction through a SiO2 layer studied by electrochemical impedance analysis. Electrochem commun 2017. [DOI: 10.1016/j.elecom.2017.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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49
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Kim EJ, Jeon CS, Hwang I, Chung TD. Translocation Pathway-Dependent Assembly of Streptavidin- and Antibody-Binding Filamentous Virus-Like Particles. Small 2017; 13:1601693. [PMID: 27762503 DOI: 10.1002/smll.201601693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 09/13/2016] [Indexed: 06/06/2023]
Abstract
Compared to well-tolerated p3 fusion, the display of fast-folding proteins fused to the minor capsid p7 and the major capsid p8, as well as in vivo biotinylation of biotin acceptor peptide (AP) fused to p7, are found to be markedly inefficient using the filamentous phage. Here, to overcome such limitations, the effect of translocation pathways, amber mutation, and phage and phagemid display systems on p7 and p8 display of antibody-binding domains are examined, while comparing the level of in vivo biotinylation of AP fused to p7 or p3. Interestingly, the in vivo biotinylation of AP occurs only in p3 fusion and the fast-folding antibody-binding scaffolds fused to p7 and p8 are best displayed via a twin-arginine translocation pathway in TG1 cells. The lower the expression level of the wild-type p8 and the smaller the size of the guest protein, the better the display of Z-domain fused to the recombinant p8. The in vivo biotinylated multifunctional filamentous virus-like particles can be vertically immobilized on streptavidin (SAV)-coated microspheres to resemble cellular microvilli-like structures, which reportedly enhance protein-protein interactions due to dramatically expanded flexible surface area.
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Affiliation(s)
- Eun Joong Kim
- Department of Chemistry, Seoul National University, Seoul, 08826, Korea
| | - Chang Su Jeon
- Samsung Electronics Co., Ltd, Samsungjeonja-ro 1, Hwaseong-si, Gyeonggi-do, 18448, Korea
| | - Inseong Hwang
- Department of Chemistry, Seoul National University, Seoul, 08826, Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Korea
- Advanced Institutes of Convergence Technology, Suwon-si, Gyeonggi-do, 16229, Korea
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50
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Kim BJ, Kim YR, Seo M, Kim EJ, Jeon J, Chung TD. Electrochemical Impedance Spectroscopy at Well-Controlled dc Bias for Nanoporous Platinum Microelectrodes in Rat Embryo Brain. ChemElectroChem 2016. [DOI: 10.1002/celc.201600404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Beom Jin Kim
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Yang-Rae Kim
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
| | - Minjee Seo
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Eun Joong Kim
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Joohee Jeon
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
- Advanced Institutes of Convergence Technology; Suwon-Si Gyeonggi-do 16229 Republic of Korea
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