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Nam J, Yoo C, Seo M. Polymerization/Depolymerization-Induced Self-Assembly under Coupled Equilibria of Polymerization with Self-Assembly. J Am Chem Soc 2024; 146:13854-13861. [PMID: 38717989 DOI: 10.1021/jacs.4c00612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
Depolymerization breaks down polymer chains into monomers like unthreading beads, attracting more attention from a sustainability standpoint. When polymerization reaches equilibrium, polymerization and depolymerization can reversibly proceed by decreasing and increasing the temperature. Here, we demonstrate that such dynamic control of a growing polymer chain in a selective solvent can spontaneously modulate the self-assembly of block copolymer micellar nano-objects. Compared to polymerization-induced self-assembly (PISA), where irreversible growth of a solvophobic polymer block from the end of a solvophilic polymer causes micellization, polymerization/depolymerization-induced self-assembly presented in this study allows us to reversibly regulate the packing parameter of the forming block copolymer and thus induce reversible morphological transitions of the nano-objects by temperature swing. Under the coupled equilibria of polymerization with self-assembly, we found that demixing of the growing polymer block in a more selective solvent entropically facilitates depolymerization at a substantially lower temperature. Taking ring-opening polymerization of δ-valerolactone initiated from the hydroxyl-terminated poly(ethylene oxide) as a model system, we show that polymerization/depolymerization/repolymerization leads to reversible morphological transitions, such as rod-sphere-rod and fiber-rod-fiber, during the heating and cooling cycle and accompanied by changes in macroscopic properties such as viscosity, suggesting their potential as dynamic soft materials.
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Affiliation(s)
- Jiyun Nam
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Changsu Yoo
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Myungeun Seo
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
- KAIST Institute for the Nanocentury, KAIST, Daejeon 34141, Republic of Korea
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2
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Ahmed M, Akram MA, Bano A, Khan MZ, Rehman R, Jan R, Javed S. A key parametric study of ultrasonic exfoliation of 2D TiB 2 using DI water as a unique medium. Heliyon 2024; 10:e29417. [PMID: 38665571 PMCID: PMC11043946 DOI: 10.1016/j.heliyon.2024.e29417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/25/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
Liquid Phase Exfoliation (LPE) is a very effective technique for the synthesis of few layered two dimensional (2D) nanosheets. There is a surge to find environment friendly solvents for efficient exfoliation of layered materials to produce 2D nanosheets. TiB2 is an important layered material with very little reported work on its 2D nanosheets. The present work is about successful LPE of TiB2 using deionized (DI) water as a clean, green and low cost dispersion medium to make TiB2 nanosheets. The impact of ultrasonication conditions i.e. input power and treatment duration for efficient synthesis of few layered 2D nanosheets in DI water is studied by Atomic Force Microscopy (AFM), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It is found that by increasing input power, the layer thickness is reduced from bulk to 34 nm with lateral dimensions as huge as up to 5 μm. The increased treatment duration has further reduced the layer thickness to 21 nm associated with a decrease in lateral dimensions to about 1 μm. The mechanism of variation in the aspect ratio of the 2D nanosheets with ultrasonication power and treatment duration is explained. The optimum conditions for the fabrication of high aspect ratio 2D nanosheets of TiB2 owe to a greater acoustic cavitation intensity, an optimum treatment duration and a homogenous distribution of the cavitation events while using an appropriate size of the sonotrode in the sonicated volume during ultrasonication.
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Affiliation(s)
- Marghoob Ahmed
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
| | - Muhammad Aftab Akram
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
- Department of Materials Science and Engineering, Pak-Austria Fachhochschule Institute of Applied Sciences and Technology, Mang Haripur, 22620, Khyber Pakhtunkhwa, Pakistan
| | - Afsar Bano
- Department of Physics, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, LUMS, 54792, Lahore, Pakistan
| | - Muhammad Zafar Khan
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
| | - Rafia Rehman
- Section of Phytochemistry and Natural Products, Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, 46000, Punjab, Pakistan
| | - Rahim Jan
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
| | - Sofia Javed
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
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3
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Verma AK, Sharma BB. Experimental and Theoretical Insights into Interfacial Properties of 2D Materials for Selective Water Transport Membranes: A Critical Review. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7812-7834. [PMID: 38587122 DOI: 10.1021/acs.langmuir.4c00061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Interfacial properties, such as wettability and friction, play critical roles in nanofluidics and desalination. Understanding the interfacial properties of two-dimensional (2D) materials is crucial in these applications due to the close interaction between liquids and the solid surface. The most important interfacial properties of a solid surface include the water contact angle, which quantifies the extent of interactions between the surface and water, and the water slip length, which determines how much faster water can flow on the surface beyond the predictions of continuum fluid mechanics. This Review seeks to elucidate the mechanism that governs the interfacial properties of diverse 2D materials, including transition metal dichalcogenides (e.g., MoS2), graphene, and hexagonal boron nitride (hBN). Our work consolidates existing experimental and computational insights into 2D material synthesis and modeling and explores their interfacial properties for desalination. We investigated the capabilities of density functional theory and molecular dynamics simulations in analyzing the interfacial properties of 2D materials. Specifically, we highlight how MD simulations have revolutionized our understanding of these properties, paving the way for their effective application in desalination. This Review of the synthesis and interfacial properties of 2D materials unlocks opportunities for further advancement and optimization in desalination.
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Affiliation(s)
- Ashutosh Kumar Verma
- School of Chemical Engineering, Oklahoma State University, Stillwater, Oklahoma 74078, United States
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Akeredolu B, Ahemen I, Amah A, Onojah A, Shakya J, Gayathri H, Ghosh A. Improved liquid phase exfoliation technique for the fabrication of MoS 2/graphene heterostructure-based photodetector. Heliyon 2024; 10:e24964. [PMID: 38322969 PMCID: PMC10845704 DOI: 10.1016/j.heliyon.2024.e24964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 01/11/2024] [Accepted: 01/17/2024] [Indexed: 02/08/2024] Open
Abstract
2D nanosheets produced using liquid phase exfoliation method offers scalable and cost effective routes to optoelectronics devices. But this technique sometimes yields high defect, low stability, and compromised electronic properties. In this work, we employed an innovative approach that improved the existing liquid phase exfoliation method for fabricating MoS2/graphene heterostructure-based photodetector with enhanced optoelectronic properties. This technique involves hydrothermally treating MoS2 before dispersing it in a carefully chosen and environmentally friendly IPA/water solvent for ultrasonication exfoliation through an optomechanical approach. Thereafter, heterostructure nanosheets of MoS2 and graphene were formed through sequential deposition technique for the fabrication of vertical heterojunctions. Furthermore, we achieved a vertically stacked MoS2/graphene photodetector and a bare MoS2 photodetector. The MoS2/graphene hybrid nanosheets were characterized using spectroscopic and microscopic techniques. The results obtained show the size of the nanosheets is between 350 and 500 nm on average, and their thickness is less than or equal to 5 nm, and high crystallinity in the 2H semiconducting phase. The photocurrent, photoresponsivity, external quantum efficiency (EQE), and specific detectivity of MoS2/graphene heterostructure at 4 V bias voltage and 650 nm illumination wavelength were 3.55 μA, 39.44 mA/W, 7.54 %, and 2.02 × 1010 Jones, respectively, and that of MoS2 photodetector are 0.55 μA, 6.11 mA/W, 1.16 %, and 3.4 × 109 Jones. The results presented indicate that the photoresponse performances of the as-prepared MoS2/graphene were greatly improved (about 7-fold) compared to the photoresponse of the sole MoS2. Again, the MoS2/graphene heterostructure fabricated in this work show better optoelectronic characteristics as compared to the similar heterostructure prepared using the conventional solution processed method. The results provide a modest, inexpensive, and efficient method to fabricate heterojunctions with improved optoelectronic performance.
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Affiliation(s)
- B.J. Akeredolu
- Department of Physics Joseph Sarwuan Tarka University, Makurdi, P.M.B. 2373, Nigeria
- Department of Pure and Applied Physics Federal University, Wukari, P.M.B 1020, Nigeria
- Department of Physics, Indian Institute of Science, Bangalore, 560012, India
| | - I. Ahemen
- Department of Physics Joseph Sarwuan Tarka University, Makurdi, P.M.B. 2373, Nigeria
| | - A.N. Amah
- Department of Physics Joseph Sarwuan Tarka University, Makurdi, P.M.B. 2373, Nigeria
| | - A.D. Onojah
- Department of Physics Joseph Sarwuan Tarka University, Makurdi, P.M.B. 2373, Nigeria
| | - Jyoti Shakya
- Department of Physics, Indian Institute of Science, Bangalore, 560012, India
| | - H.N. Gayathri
- Department of Physics, Indian Institute of Science, Bangalore, 560012, India
| | - Arindam Ghosh
- Department of Physics, Indian Institute of Science, Bangalore, 560012, India
- Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore, 560012, India
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5
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Noureen S, Rehman SU, Batool SM, Ali J, Zhang Q, Batool SS, Wang Y, Li C. Tailoring Bi 2Se 3 Topological Insulator for Visible-NIR Photodetectors with Schottky Contacts Using Liquid Phase Exfoliation. ACS APPLIED MATERIALS & INTERFACES 2024; 16:8158-8168. [PMID: 38301155 DOI: 10.1021/acsami.3c15315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Layered semiconductors of the V-VI group have attracted considerable attention in optoelectronic applications owing to their atomically thin structures. They offer thickness-dependent optical and electronic properties, promising ultrafast response time, and high sensitivity. Compared to the bulk, 2D bismuth selenide (Bi2Se3) is recently considered a highly promising material. In this study, 2D nanosheets are synthesized by prolonged sonication in two different solvents, such as N-methyl-2-pyrrolidone (NMP) and chitosan-acetic acid solution (CS-HAc), using the liquid-phase exfoliation (LPE) method. X-ray diffraction confirms the amorphous nature of exfoliated 2D nanosheets with maximum peak intensity at the same position (015) crystal plane as that obtained in its bulk counterpart. SEM confirms the thin 2D nanosheet-like morphology. Successful exfoliation of Bi2Se3 nanosheets up to five layers is achieved using CS-HAc solvent. The as-synthesized 2D nanosheets in different solvents are employed to fabricate the photodetector. At minimum selected power density, the photodetector fabricated using exfoliated ultrathin 2D nanosheets exhibits the highest range of responsivity, varying from 15 to 2.5 mA/W, and detectivity ranging from 2.83 × 109 to 6.37 × 107. Ultrathin 2D Bi2Se3 nanosheets have fast rise and fall times, ranging from 0.01 to 0.12 and 0.01 to 0.06 s, respectively, at different wavelengths. Ultrathin Bi2Se3 nanosheets have improved photodetection parameters as compared to multilayered nanosheets due to the high surface to volume ratio, reduced recombination and trapping of charge carrier, improved carrier confinement, and faster carrier transport due to the thin layer.
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Affiliation(s)
- Sadaf Noureen
- School of Science, Minzu University of China, Beijing 100081, China
- Optoelectronic Research Laboratory (OERL), Department of Physics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad 45550, Pakistan
| | - Sajid Ur Rehman
- School of Science, Minzu University of China, Beijing 100081, China
| | - Syeda Maria Batool
- Electric Material and Nanotechnology Lab, North Dakota State University, Fargo, North Dakota 58102, United States
| | - Junaid Ali
- Optoelectronic Research Laboratory (OERL), Department of Physics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad 45550, Pakistan
| | - Qifeng Zhang
- Electric Material and Nanotechnology Lab, North Dakota State University, Fargo, North Dakota 58102, United States
| | - Syeda Sitwat Batool
- School of Science, Minzu University of China, Beijing 100081, China
- Optoelectronic Research Laboratory (OERL), Department of Physics, COMSATS University Islamabad, Park Road, Chak Shahzad, Islamabad 45550, Pakistan
| | - Yang Wang
- School of Science, Minzu University of China, Beijing 100081, China
- Optoelectronics Research Center, Minzu University of China, Beijing 100081, China
| | - Chuanbo Li
- School of Science, Minzu University of China, Beijing 100081, China
- Optoelectronics Research Center, Minzu University of China, Beijing 100081, China
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6
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Gotzias A, Lazarou YG. Graphene Exfoliation in Binary NMP/Water Mixtures by Molecular Dynamics Simulations. Chempluschem 2024:e202300758. [PMID: 38314614 DOI: 10.1002/cplu.202300758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 02/06/2024]
Abstract
We investigate the molecular mechanism underlying the liquid-phase exfoliation of graphene in aqueous/N-methyl-2-pyrrolidone (NMP) solvent mixtures and calculate the associated free energies, considering different NMP concentrations and exfoliation temperatures. We employ steered molecular dynamics to establish a path for the exfoliation of a graphene sheet from graphite within each solvent environment. Then, we conduct umbrella sampling simulations throughout the created paths to compute the potential of mean force (PMF) of the graphene sheet. As the exfoliated nanosheet disperses into the liquid, it becomes fully covered by an adsorbed solvent monolayer. We analyze the composition of the monolayer by measuring the direct contacts of either NMP or water molecules with the carbon surface. The carbon surface exhibits a preference for adsorbing NMP over water. The NMP molecules form a hydrophobic compact monolayer structure, effectively protecting the carbon interface from unfavorable interactions with water. The creation of the hydrophobic monolayer is a key factor in the exfoliation process, as it effectively inhibits the restacking of exfoliated nanosheets. An adequate level of graphene solubility is achieved through the addition of 20 % to 30 % water by weight to the NMP solvent. This finding holds significant importance for improving production efficiency and reducing dependence on organic solvents in the industrial manufacturing of graphene.
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Affiliation(s)
- A Gotzias
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece
| | - Y G Lazarou
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece
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7
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Chavalekvirat P, Nakkiew P, Kunaneksin T, Hirunpinyopas W, Busayaporn W, Iamprasertkun P. Tuning Surface Energy to Enhance MoS 2 Nanosheet Production via Liquid-Phase Exfoliation: Understanding the Electrochemical Adsorption of Cesium Chloride. Inorg Chem 2023; 62:12851-12861. [PMID: 37526701 DOI: 10.1021/acs.inorgchem.3c01508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Environmental pollution caused by radionuclides like Cs-137 and Cs-134 has increased global attention toward public health. Electrochemical adsorption has emerged as a feasible, rapid, and scalable method to treat contaminated water sources. However, graphene and its derivatives have limitations in ion adsorption via physisorption, forming a double layer that restricts the electrode's adsorption capacity. To address this, we propose the use of molybdenum disulfide (MoS2) with its extensive intercalation galleries of MoS2 nanosheets for cesium removal via an electrochemical route. Liquid-phase exfoliation with water and N-methyl-2-pyrrolidone (NMP) was then used to produce MoS2 nanosheets in a scalable quantity (high-yield production). The formation of a mixed solvent possessing relatively equivalent surface energy for exfoliation enabled us to achieve a remarkable exfoliation yield of up to ca. 1.26 mg mL-1, which is one of the highest yields reported to date (without a surfactant being added) and to the best of our knowledge. The 35% v/v of water in NMP displayed a maximum yield while maintaining the structure of the as-exfoliated one. Water exceeding over 66.7% v/v led to the formation of MoO3. Moreover, an insight into the cesium ion removal mechanism through the electrochemical route was demonstrated. It is found that the Cs+ removal follows electrochemical intercalation rather than adsorption. This work aids the understanding of cesium intercalation coupled with a mass-scale production method, which should lead to more efficient and cost-effective removal of radionuclides from contaminated water sources, opening new research avenues in materials and environmental science.
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Affiliation(s)
- Panwad Chavalekvirat
- School of Bio-Chemical Engineering and Technology, Sirindhron International Institute of Technology, Thammasat University, Khlong Luang, Pathum Thani 12120, Thailand
| | - Patlapa Nakkiew
- School of Bio-Chemical Engineering and Technology, Sirindhron International Institute of Technology, Thammasat University, Khlong Luang, Pathum Thani 12120, Thailand
| | - Tanatat Kunaneksin
- School of Bio-Chemical Engineering and Technology, Sirindhron International Institute of Technology, Thammasat University, Khlong Luang, Pathum Thani 12120, Thailand
| | - Wisit Hirunpinyopas
- Department of Chemistry and Centre of Excellence for Innovation in Chemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
| | - Wutthikrai Busayaporn
- Synchrotron Light Research Institute (Public Organization), 111 University Avenue, Muang, Nakhon Ratchasima 30000, Thailand
| | - Pawin Iamprasertkun
- School of Bio-Chemical Engineering and Technology, Sirindhron International Institute of Technology, Thammasat University, Khlong Luang, Pathum Thani 12120, Thailand
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8
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Zhang CJ, Schneider R, Jafarpour M, Nüesch F, Abdolhosseinzadeh S, Heier J. Micro-Cup Architecture for Printing and Coating Asymmetric 2d-Material-Based Solid-State Supercapacitors. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300357. [PMID: 37078837 DOI: 10.1002/smll.202300357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/29/2023] [Indexed: 05/03/2023]
Abstract
High energy density micro-supercapacitors (MSCs) are in high demand for miniaturized electronics and microsystems. Research efforts today focus on materials development, applied in the planar interdigitated, symmetric electrode architecture. A novel "cup & core" device architecture that allows for printing of asymmetric devices without the need of accurately positioning the second finger electrode here have been introduced. The bottom electrode is either produced by laser ablation of a blade-coated graphene layer or directly screen-printed with graphene inks to create grids with high aspect ratio walls forming an array of "micro-cups". A quasi-solid-state ionic liquid electrolyte is spray-deposited on the walls; the top electrode material -MXene inks- is then spray-coated to fill the cup structure. The architecture combines the advantages of interdigitated electrodes for facilitated ion-diffusion, which is critical for 2D-material-based energy storage systems by providing vertical interfaces with the layer-by-layer processing of the sandwich geometry. Compared to flat reference devices, volumetric capacitance of printed "micro-cups" MSC increased considerably, while the time constant decreased (by 58%). Importantly, the high energy density (3.99 µWh cm-2 ) of the "micro-cups" MSC is also superior to other reported MXene and graphene-based MSCs.
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Affiliation(s)
- Chuanfang John Zhang
- College of Materials Science & Engineering, Sichuan University, Chengdu, Sichuan, 610065, P. R. China
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, Dübendorf, CH-8600, Switzerland
| | - René Schneider
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, Dübendorf, CH-8600, Switzerland
| | - Mohammad Jafarpour
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, Dübendorf, CH-8600, Switzerland
- Institute of Materials Science and Engineering, Ecole Polytechnique Fedérale de Lausanne (EPFL), Station 12, Lausanne, CH-1015, Switzerland
| | - Frank Nüesch
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, Dübendorf, CH-8600, Switzerland
- Institute of Materials Science and Engineering, Ecole Polytechnique Fedérale de Lausanne (EPFL), Station 12, Lausanne, CH-1015, Switzerland
| | - Sina Abdolhosseinzadeh
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, Dübendorf, CH-8600, Switzerland
- Institute of Materials Science and Engineering, Ecole Polytechnique Fedérale de Lausanne (EPFL), Station 12, Lausanne, CH-1015, Switzerland
| | - Jakob Heier
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, Dübendorf, CH-8600, Switzerland
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Adam J, Singh M, Abduvakhidov A, Del Sorbo MR, Feoli C, Hussain F, Kaur J, Mirabella A, Rossi M, Sasso A, Valadan M, Varra M, Rusciano G, Altucci C. The Effectiveness of Cyrene as a Solvent in Exfoliating 2D TMDs Nanosheets. Int J Mol Sci 2023; 24:10450. [PMID: 37445624 DOI: 10.3390/ijms241310450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 06/09/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
The pursuit of environmentally friendly solvents has become an essential research topic in sustainable chemistry and nanomaterial science. With the need to substitute toxic solvents in nanofabrication processes becoming more pressing, the search for alternative solvents has taken on a crucial role in this field. Additionally, the use of toxic, non-economical organic solvents, such as N-methyl-2 pyrrolidone and dimethylformamide, is not suitable for all biomedical applications, even though these solvents are often considered as the best exfoliating agents for nanomaterial fabrication. In this context, the success of producing two-dimensional transition metal dichalcogenides (2D TMDs), such as MoS2 and WS2, with excellent captivating properties is due to the ease of synthesis based on environment-friendly, benign methods with fewer toxic chemicals involved. Herein, we report for the first time on the use of cyrene as an exfoliating agent to fabricate monolayer and few-layered 2D TMDs with a versatile, less time-consuming liquid-phase exfoliation technique. This bio-derived, aprotic, green and eco-friendly solvent produced a stable, surfactant-free, concentrated 2D TMD dispersion with very interesting features, as characterized by UV-visible and Raman spectroscopies. The surface charge and morphology of the fabricated nanoflakes were analyzed using ς-potential and scanning electron microscopy. The study demonstrates that cyrene is a promising green solvent for the exfoliation of 2D TMD nanosheets with potential advantages over traditional organic solvents. The ability to produce smaller-sized-especially in the case of WS2 as compared to MoS2-and mono/few-layered nanostructures with higher negative surface charge values makes cyrene a promising candidate for various biomedical and electronic applications. Overall, the study contributes to the development of sustainable and environmentally friendly methods for the production of 2D nanomaterials for various applications.
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Affiliation(s)
- Jaber Adam
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Manjot Singh
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Italy National Institute of Nuclear Physics, Naples Section, 80126 Naples, Italy
| | | | - Maria Rosaria Del Sorbo
- Department of Precision Medicine, Università degli Studi della Campania "L. Vanvitelli", 80138 Naples, Italy
| | - Chiara Feoli
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
| | - Fida Hussain
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Jasneet Kaur
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Antonia Mirabella
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Department of Agricultural Sciences, University of Naples "Federico II", 80131 Naples, Italy
| | - Manuela Rossi
- Department of Earth Science, Environment and Resources, University of Naples "Federico II", 80131 Naples, Italy
- Istituto di Cristallografia-CNR, Via G. Amendola 122/O, 70126 Bari, Italy
| | - Antonio Sasso
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Mohammadhassan Valadan
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Italy National Institute of Nuclear Physics, Naples Section, 80126 Naples, Italy
| | - Michela Varra
- Department of Pharmacy, University of Naples "Federico II", 80131 Naples, Italy
| | - Giulia Rusciano
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Carlo Altucci
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Italy National Institute of Nuclear Physics, Naples Section, 80126 Naples, Italy
- ISASI-CNR, Institute of Applied Sciences and Intelligent Systems "Eduardo Caianiello", 80078 Naples, Italy
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10
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Thoutam LR, Mathew R, Ajayan J, Tayal S, Nair SV. A critical review of fabrication challenges and reliability issues in top/bottom gated MoS 2field-effect transistors. NANOTECHNOLOGY 2023; 34:232001. [PMID: 36731113 DOI: 10.1088/1361-6528/acb826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
The voyage of semiconductor industry to decrease the size of transistors to achieve superior device performance seems to near its physical dimensional limitations. The quest is on to explore emerging material systems that offer dimensional scaling to match the silicon- based technologies. The discovery of atomic flat two-dimensional materials has opened up a completely new avenue to fabricate transistors at sub-10 nanometer level which has the potential to compete with modern silicon-based semiconductor devices. Molybdenum disulfide (MoS2) is a two-dimensional layered material with novel semiconducting properties at atomic level seems like a promising candidate that can possibly meet the expectation of Moore's law. This review discusses the various 'fabrication challenges' in making MoS2based electronic devices from start to finish. The review outlines the intricate challenges of substrate selection and various synthesis methods of mono layer and few-layer MoS2. The review focuses on the various techniques and methods to minimize interface defect density at substrate/MoS2interface for optimum MoS2-based device performance. The tunable band-gap of MoS2with varying thickness presents a unique opportunity for contact engineering to mitigate the contact resistance issue using different elemental metals. In this work, we present a comprehensive overview of different types of contact materials with myriad geometries that show a profound impact on device performance. The choice of different insulating/dielectric gate oxides on MoS2in co-planar and vertical geometry is critically reviewed and the physical feasibility of the same is discussed. The experimental constraints of different encapsulation techniques on MoS2and its effect on structural and electronic properties are extensively discussed.
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Affiliation(s)
- Laxman Raju Thoutam
- Amrita School of Nanosciences and Molecular Medicine, Amrita Vishwa Vidyapeetham, Ponekkara, Kochi 682041, India
| | - Ribu Mathew
- School of Electrical & Electronics Engineering, VIT Bhopal University, Bhopal, 466114, India
| | - J Ajayan
- Department of Electronics and Communication Engineering, SR University, Warangal, 506371, India
| | - Shubham Tayal
- Department of Electronics and Communication Engineering, SR University, Warangal, 506371, India
| | - Shantikumar V Nair
- Amrita School of Nanosciences and Molecular Medicine, Amrita Vishwa Vidyapeetham, Ponekkara, Kochi 682041, India
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11
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Kotsidi M, Gorgolis G, Pastore Carbone MG, Paterakis G, Anagnostopoulos G, Trakakis G, Manikas AC, Pavlou C, Koutroumanis N, Galiotis C. Graphene nanoplatelets and other 2D-materials as protective means against the fading of coloured inks, dyes and paints. NANOSCALE 2023; 15:5414-5428. [PMID: 36826806 PMCID: PMC10019573 DOI: 10.1039/d2nr05795f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
The present work demonstrates the ability of graphene nanoplatelets (GNPs) and other two-dimensional materials (2DMs) like tungsten disulfide (WS2), molybdenum disulfide (MoS2) and hexagonal boron nitride (hBN) to act as protective barriers against the fading of architectural paints and also inks/paints used in art. The results present a new approach for improving the lightfastness of colours of artworks and painted indoor/outdoor wall surfaces taking advantage of the remarkable properties of 2DMs. As shown herein, commercial inks and architectural paints of different colours doped with graphene nanoplatelets (GNPs), graphene oxide (GO), reduced graphene oxide (rGO) and other 2DMs, exhibit a superior resistance to fading under ultraviolet radiation or even under exposure to visible light. A spectroscopic study on these inks and dyes reveals that the peaks which are characteristic of the colour pigments are less affected from aging/fading when the GNPs and the other 2DMs are present. The protection mechanism for the GNPs and the other 2DMs differs. For GNPs, mainly their high surface area which leads to free radicals scavenging (especially hydroxyl radicals), and secondarily their UV absorption, are responsible for their protection effects, while for GO, a transition to rGO structures and consequently to 'smart' paints can be observed after the performed aging routes. In this way, the paint gets improved by time preventing or slowing its own fading and decolorization. For the other 2DMs, the transition-metal dichalcogenides performed better than hBN, even though they all absorb in the UV region. This can be ascribed to the facts that the formers also absorb in the visible, while hBN does not, while most importantly, they can trap reactive oxygen species (ROS) and corrosive gases in their structure as opposed to hBN. By conducting colorimetric measurements, we have discovered that the lifetime of the as-developed 2DM-doped inks and paints can be extended by up to ∼40%.
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Affiliation(s)
- M Kotsidi
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
- Department of Chemical Engineering, University of Patras, Patras 26504, Greece
| | - G Gorgolis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
- Department of Chemical Engineering, University of Patras, Patras 26504, Greece
| | - M G Pastore Carbone
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
| | - G Paterakis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
| | - G Anagnostopoulos
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
| | - G Trakakis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
| | - A C Manikas
- Department of Chemical Engineering, University of Patras, Patras 26504, Greece
| | - C Pavlou
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
| | - N Koutroumanis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
| | - C Galiotis
- Institute of Chemical Engineering Sciences, Foundation for Research and Technology - Hellas (FORTH/ICE-HT), Patras 265 04, Greece.
- Department of Chemical Engineering, University of Patras, Patras 26504, Greece
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12
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The Quest for Green Solvents for the Sustainable Production of Nanosheets of Two-Dimensional (2D) Materials, a Key Issue in the Roadmap for the Ecology Transition in the Flatland. Molecules 2023; 28:molecules28031484. [PMID: 36771151 PMCID: PMC9919378 DOI: 10.3390/molecules28031484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/19/2023] [Accepted: 01/25/2023] [Indexed: 02/05/2023] Open
Abstract
The recent advent of two-dimensional (2D) materials has had a ground-breaking impact on science and technology. To exploit in technology their unique thickness-dependent physicochemical properties, the large-scale production of 2D materials is mandatory, but it represents an open challenge still due to various pitfalls and severe limitations including the toxicity of state-of-the-art solvents. Thus, liquid-phase exfoliation based on green and bioderived solvents represents an ideal methodology for massive production. This is particularly crucial for introducing 2D materials in technological applications such as the production of drinking water and agri-food industrial processes. Here, we assessed the production of 2D nanosheets (specifically, graphene, WS2, MoS2) with liquid-phase exfoliation assisted by eco-friendly solvents, with a comparative evaluation of green solvents in terms of the yield and, moreover, the aspect ratio, defectivity, and crystalline quality of the produced nanosheets. In particular, we focus on the most promising green solvents in terms of the yield and the crystalline quality of the produced nanosheets: Polarclean, Iris, and Cyrene, which were compared with acetone/water mixtures, isopropyl alcohol (IPA), triethanolamine (TEA), aqueous solutions of urea, and an ethanol/water mixture as well as two toxic solvents largely used for the production of 2D nanosheets: N-methyl-2-pyrrolidone (NMP) and N, N-dimethylformamide (DMF). Remarkably, the density of defects was particularly low in the liquid-phase exfoliation with Polarclean, as indicated by the Raman spectrum of graphene, with the I(D)/I(G) ratio below 0.1. Furthermore, Polarclean and Iris also enable ink-jet printing with functional inks of 2D materials based on green solvents due to their low dynamic viscosity at room temperature.
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13
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Giri A, Park G, Jeong U. Layer-Structured Anisotropic Metal Chalcogenides: Recent Advances in Synthesis, Modulation, and Applications. Chem Rev 2023; 123:3329-3442. [PMID: 36719999 PMCID: PMC10103142 DOI: 10.1021/acs.chemrev.2c00455] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The unique electronic and catalytic properties emerging from low symmetry anisotropic (1D and 2D) metal chalcogenides (MCs) have generated tremendous interest for use in next generation electronics, optoelectronics, electrochemical energy storage devices, and chemical sensing devices. Despite many proof-of-concept demonstrations so far, the full potential of anisotropic chalcogenides has yet to be investigated. This article provides a comprehensive overview of the recent progress made in the synthesis, mechanistic understanding, property modulation strategies, and applications of the anisotropic chalcogenides. It begins with an introduction to the basic crystal structures, and then the unique physical and chemical properties of 1D and 2D MCs. Controlled synthetic routes for anisotropic MC crystals are summarized with example advances in the solution-phase synthesis, vapor-phase synthesis, and exfoliation. Several important approaches to modulate dimensions, phases, compositions, defects, and heterostructures of anisotropic MCs are discussed. Recent significant advances in applications are highlighted for electronics, optoelectronic devices, catalysts, batteries, supercapacitors, sensing platforms, and thermoelectric devices. The article ends with prospects for future opportunities and challenges to be addressed in the academic research and practical engineering of anisotropic MCs.
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Affiliation(s)
- Anupam Giri
- Department of Chemistry, Faculty of Science, University of Allahabad, Prayagraj, UP-211002, India
| | - Gyeongbae Park
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Cheongam-Ro 77, Nam-Gu, Pohang, Gyeongbuk790-784, Korea.,Functional Materials and Components R&D Group, Korea Institute of Industrial Technology, Gwahakdanji-ro 137-41, Sacheon-myeon, Gangneung, Gangwon-do25440, Republic of Korea
| | - Unyong Jeong
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Cheongam-Ro 77, Nam-Gu, Pohang, Gyeongbuk790-784, Korea
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14
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Paolucci V, De Santis J, Ricci V, Lozzi L, Giorgi G, Cantalini C. Bidimensional Engineered Amorphous a-SnO 2 Interfaces: Synthesis and Gas Sensing Response to H 2S and Humidity. ACS Sens 2022; 7:2058-2068. [PMID: 35757893 PMCID: PMC9315963 DOI: 10.1021/acssensors.2c00887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two-dimensional (2D) transition metal dichalcogenides (TMDs) and metal chalcogenides (MCs), despite their excellent gas sensing properties, are subjected to spontaneous oxidation in ambient air, negatively affecting the sensor's signal reproducibility in the long run. Taking advantage of spontaneous oxidation, we synthesized fully amorphous a-SnO2 2D flakes (≈30 nm thick) by annealing in air 2D SnSe2 for two weeks at temperatures below the crystallization temperature of SnO2 (T < 280 °C). These engineered a-SnO2 interfaces, preserving all the precursor's 2D surface-to-volume features, are stable in dry/wet air up to 250 °C, with excellent baseline and sensor's signal reproducibility to H2S (400 ppb to 1.5 ppm) and humidity (10-80% relative humidity (RH)) at 100 °C for one year. Specifically, by combined density functional theory and ab initio molecular dynamics, we demonstrated that H2S and H2O compete by dissociative chemisorption over the same a-SnO2 adsorption sites, disclosing the humidity cross-response to H2S sensing. Tests confirmed that humidity decreases the baseline resistance, hampers the H2S sensor's signal (i.e., relative response (RR) = Ra/Rg), and increases the limit of detection (LOD). At 1 ppm, the H2S sensor's signal decreases from an RR of 2.4 ± 0.1 at 0% RH to 1.9 ± 0.1 at 80% RH, while the LOD increases from 210 to 380 ppb. Utilizing a suitable thermal treatment, here, we report an amorphization procedure that can be easily extended to a large variety of TMDs and MCs, opening extraordinary applications for 2D layered amorphous metal oxide gas sensors.
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Affiliation(s)
- Valentina Paolucci
- Department of Industrial and Information Engineering and Economics, University of L'Aquila and UdR INSTM of L'Aquila, Via G. Gronchi 18, I-67100 L'Aquila, Italy
| | - Jessica De Santis
- Department of Industrial and Information Engineering and Economics, University of L'Aquila and UdR INSTM of L'Aquila, Via G. Gronchi 18, I-67100 L'Aquila, Italy
| | - Vittorio Ricci
- Department of Industrial and Information Engineering and Economics, University of L'Aquila and UdR INSTM of L'Aquila, Via G. Gronchi 18, I-67100 L'Aquila, Italy
| | - Luca Lozzi
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, 67100 L'Aquila (AQ), Italy
| | - Giacomo Giorgi
- Department of Civil & Environmental Engineering (DICA), Università degli Studi di Perugia, Via G. Duranti 93, 06125 Perugia, Italy.,CNR-SCITEC, 06123 Perugia, Italy
| | - Carlo Cantalini
- Department of Industrial and Information Engineering and Economics, University of L'Aquila and UdR INSTM of L'Aquila, Via G. Gronchi 18, I-67100 L'Aquila, Italy
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15
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Fernandes J, Nemala SS, De Bellis G, Capasso A. Green Solvents for the Liquid Phase Exfoliation Production of Graphene: The Promising Case of Cyrene. Front Chem 2022; 10:878799. [PMID: 35480388 PMCID: PMC9037782 DOI: 10.3389/fchem.2022.878799] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 03/11/2022] [Indexed: 11/30/2022] Open
Abstract
The liquid phase exfoliation (LPE) of graphite has allowed to produce graphene materials on a large scale and at a reasonable cost. By this method, stable dispersions, inks and liquid suspensions containing atomic-thick graphene flakes with tailored concentrations can be produced, opening up applications in a wide range of cutting-edge technologies such as functional coatings, printed and flexible electronics, and composites. However, currently established LPE techniques raise several health and environmental risks, since unsafe and toxic solvents (such as NMP, DMF, and DMSO) are often regarded as the most effective liquid media for the process. Therefore, it appears necessary to unlock eco-friendly and sustainable methods for the production of graphene at an industrial scale. This review focuses on the latest developments in terms of green solvents for LPE production of graphene. We highlight the use of a new green solvent, Cyrene, and its performance when compared to conventional solvents.
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Affiliation(s)
- João Fernandes
- International Iberian Nanotechnology Laboratory, Braga, Portugal
| | | | - Giovanni De Bellis
- Department of Astronautical, Electrical and Energy Engineering, Sapienza University of Rome, Rome, Italy
- Research Center on Nanotechnology Applied to Engineering of Sapienza (CNIS), Sapienza University of Rome, Rome, Italy
| | - Andrea Capasso
- International Iberian Nanotechnology Laboratory, Braga, Portugal
- *Correspondence: Andrea Capasso,
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16
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Pereira N, Rezende N, Cunha THR, Barboza APM, Silva GG, Lippross D, Neves BRA, Chacham H, Ferlauto AS, Lacerda RG. Aerosol-Printed MoS 2 Ink as a High Sensitivity Humidity Sensor. ACS OMEGA 2022; 7:9388-9396. [PMID: 35356695 PMCID: PMC8945157 DOI: 10.1021/acsomega.1c06525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/01/2022] [Indexed: 05/13/2023]
Abstract
Molybdenum disulfide (MoS2) is attractive for use in next-generation nanoelectronic devices and exhibits great potential for humidity sensing applications. Herein, MoS2 ink was successfully prepared via a simple exfoliation method by sonication. The structural and surface morphology of a deposited ink film was analyzed by scanning electron microscopy (SEM), Raman spectroscopy, and atomic force microscopy (AFM). The aerosol-printed MoS2 ink sensor has high sensitivity, with a conductivity increase by 6 orders of magnitude upon relative humidity increase from 10 to 95% at room temperature. The sensor also has fast response/recovery times and excellent repeatability. Possible mechanisms for the water-induced conductivity increase are discussed. An analytical model that encompasses two ionic conduction regimes, with a percolation transition to an insulating state below a low humidity threshold, describes the sensor response successfully. In conclusion, our work provides a low-cost and straightforward strategy for fabricating a high-performance humidity sensor and fundamental insights into the sensing mechanism.
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Affiliation(s)
- Neuma
M. Pereira
- Departamento
de Física, Universidade Federal de
Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
- Departamento
de Química, Universidade Federal
de Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
- Centro
de Tecnologia em Nanomateriais e Grafeno/UFMG, Universidade Federal de Minas Gerais, BHtec, Belo Horizonte, Minas Gerais 31310-260, Brazil
| | - Natália
P. Rezende
- Departamento
de Física, Universidade Federal de
Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
- Centro
de Tecnologia em Nanomateriais e Grafeno/UFMG, Universidade Federal de Minas Gerais, BHtec, Belo Horizonte, Minas Gerais 31310-260, Brazil
| | - Thiago H. R. Cunha
- Departamento
de Física, Universidade Federal de
Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
- Centro
de Tecnologia em Nanomateriais e Grafeno/UFMG, Universidade Federal de Minas Gerais, BHtec, Belo Horizonte, Minas Gerais 31310-260, Brazil
| | - Ana P. M. Barboza
- Departamento
de Física, Universidade Federal de
Ouro Preto, Ouro Preto, Minas Gerais 35400-000, Brazil
| | - Glaura G. Silva
- Departamento
de Química, Universidade Federal
de Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
- Centro
de Tecnologia em Nanomateriais e Grafeno/UFMG, Universidade Federal de Minas Gerais, BHtec, Belo Horizonte, Minas Gerais 31310-260, Brazil
| | - Daniel Lippross
- Departamento
de Química, Universidade Federal
de Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
| | - Bernardo R. A. Neves
- Departamento
de Física, Universidade Federal de
Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
| | - Hélio Chacham
- Departamento
de Física, Universidade Federal de
Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
| | - Andre S. Ferlauto
- Centro
de Tecnologia em Nanomateriais e Grafeno/UFMG, Universidade Federal de Minas Gerais, BHtec, Belo Horizonte, Minas Gerais 31310-260, Brazil
- Centro
de Engenharia, Modelagem e Ciências Sociais Aplicadas, Universidade Federal do ABC, Santo André, São
Paulo 09210-580, Brazil
| | - Rodrigo G. Lacerda
- Departamento
de Física, Universidade Federal de
Minas Gerais, Belo Horizonte, Minas Gerais 31270-90, Brazil
- Centro
de Tecnologia em Nanomateriais e Grafeno/UFMG, Universidade Federal de Minas Gerais, BHtec, Belo Horizonte, Minas Gerais 31310-260, Brazil
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