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Caron AJ, Ali IJ, Delgado MJ, Johnson D, Reeks JM, Strzhemechny YM, McGillivray SM. Zinc oxide nanoparticles mediate bacterial toxicity in Mueller-Hinton Broth via Zn 2. Front Microbiol 2024; 15:1394078. [PMID: 38711974 PMCID: PMC11070567 DOI: 10.3389/fmicb.2024.1394078] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 04/08/2024] [Indexed: 05/08/2024] Open
Abstract
As antibiotic resistance increases and antibiotic development dwindles, new antimicrobial agents are needed. Recent advances in nanoscale engineering have increased interest in metal oxide nanoparticles, particularly zinc oxide nanoparticles, as antimicrobial agents. Zinc oxide nanoparticles are promising due to their broad-spectrum antibacterial activity and low production cost. Despite many studies demonstrating the effectiveness of zinc oxide nanoparticles, the antibacterial mechanism is still unknown. Previous work has implicated the role of reactive oxygen species such as hydrogen peroxide, physical damage of the cell envelope, and/or release of toxic Zn2+ ions as possible mechanisms of action. To evaluate the role of these proposed methods, we assessed the susceptibility of S. aureus mutant strains, ΔkatA and ΔmprF, to zinc oxide nanoparticles of approximately 50 nm in size. These assays demonstrated that hydrogen peroxide and electrostatic interactions are not crucial for mediating zinc oxide nanoparticle toxicity. Instead, we found that Zn2+ accumulates in Mueller-Hinton Broth over time and that removal of Zn2+ through chelation reverses this toxicity. Furthermore, we found that the physical separation of zinc oxide nanoparticles and bacterial cells using a semi-permeable membrane still allows for growth inhibition. We concluded that soluble Zn2+ is the primary mechanism by which zinc oxide nanoparticles mediate toxicity in Mueller-Hinton Broth. Future work investigating how factors such as particle morphology (e.g., size, polarity, surface defects) and media contribute to Zn2+ dissolution could allow for the synthesis of zinc oxide nanoparticles that possess chemical and morphological properties best suited for antibacterial efficacy.
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Affiliation(s)
- Alexander J. Caron
- Department of Biology, Texas Christian University, Fort Worth, TX, United States
| | - Iman J. Ali
- Department of Biology, Texas Christian University, Fort Worth, TX, United States
| | - Michael J. Delgado
- Department of Biology, Texas Christian University, Fort Worth, TX, United States
| | - Dustin Johnson
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, United States
| | - John M. Reeks
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, United States
| | - Yuri M. Strzhemechny
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, United States
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2
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Olejnik-Fehér N, Jędrzejewska M, Wolska-Pietkiewicz M, Lee D, Paëpe GD, Lewiński J. On the Fate of Lithium Ions in Sol-Gel Derived Zinc Oxide Nanocrystals. Small 2024:e2309984. [PMID: 38497489 DOI: 10.1002/smll.202309984] [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: 11/02/2023] [Revised: 02/28/2024] [Indexed: 03/19/2024]
Abstract
Among diverse chemical synthetic approaches to zinc oxide nanocrystals (ZnO NCs), ubiquitous inorganic sol-gel methodology proved crucial for advancements in ZnO-based nanoscience. Strikingly, unlike the exquisite level of control over morphology and size dispersity achieved in ZnO NC syntheses, the purity of the crystalline phase, as well as the understanding of the surface structure and the character of the inorganic-organic interface, have been limited to vague descriptors until very recently. Herein, ZnO NCs applying the standard sol-gel synthetic protocol are synthesized with zinc acetate and lithium hydroxide and tracked the integration of lithium (Li) cations into the interior and exterior of nanoparticles by combining various techniques, including advanced solid-state NMR methods. In contrast to common views, it is demonstrated that Li+ ions remain kinetically trapped in the inorganic core, enter into a shallow subsurface layer, and generate "swelling" of the surface and interface regions. Thus, this work enabled both the determination of the NCs' structural imperfections and an in-depth understanding of the unappreciated role of the Li+ ions in impacting the doping and the passivation of sol-gel-derived ZnO nanomaterials.
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Affiliation(s)
- Natalia Olejnik-Fehér
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, Warsaw, 01-224, Poland
- Université Grenoble Alpes, CEA, IRIG, MEM, Grenoble, 38000, France
| | - Maria Jędrzejewska
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, Warsaw, 01-224, Poland
| | | | - Daniel Lee
- Université Grenoble Alpes, CEA, IRIG, MEM, Grenoble, 38000, France
| | - Gaël De Paëpe
- Université Grenoble Alpes, CEA, IRIG, MEM, Grenoble, 38000, France
| | - Janusz Lewiński
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, Warsaw, 01-224, Poland
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, Warsaw, 00-664, Poland
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Wusiman M, Taghipour F. A solid-phase fluorescence sensor for measuring chemical species in water. Water Res 2024; 249:120972. [PMID: 38091699 DOI: 10.1016/j.watres.2023.120972] [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] [Received: 04/01/2023] [Revised: 11/27/2023] [Accepted: 12/02/2023] [Indexed: 01/03/2024]
Abstract
In this study, the first of its kind, a solid-phase fluorescence sensing platform was developed to quantify contaminants in water. ZnO quantum dots (QDs) were combined with molecularly imprinted polymers (MIPs) to form fluorescence sensing materials. Solid sensing layers were formed via a straightforward spin-coating method, which demonstrated a strong attachment to the sensor substrate while maintaining the integrity of the sensing materials. The developed sensing platform comprised a portable fluorescence detector to measure fluorescence intensity, instead of traditional fluorescence spectroscopy. The solid sensing platform was first tested with 2,4-dichlorophenoxyacetic acid (2,4-D), demonstrating high sensitivity (0.0233) and a very strong correlation (0.98) between the target molecule concentration and sensor signal. Further, the sensing platform was successfully adapted to measure a substance with a different molecular mass and chemical structure, the algae toxin microcystin-LR (MCLR); this demonstrated the sensor's versatility in quantifying target molecules. Tap water samples spiked with MCLR were also used to test the sensor's practical application. Finally, the working mechanism of the sensing platform was established, and the key information for using the sensor to measure various contaminants was determined. With its high performance, broad applicability, and ease of use, the developed platform provides a suitable basis for lab-on-chip image-based sensing devices for environmental monitoring.
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Affiliation(s)
- Muersha Wusiman
- Chemical and Biological Engineering, University of British Columbia, Vancouver, V6T 1Z3, Canada
| | - Fariborz Taghipour
- Chemical and Biological Engineering, University of British Columbia, Vancouver, V6T 1Z3, Canada.
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4
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Zhang J, An S, Pei Y, Zhang Y, Chen J. Mechanoluminescence Affected by Trap Types and Excitation State Positions in Mg 3Ca 3(PO 4) 4:Eu 2+/Mn 2+/Ce 3+ for Multimode Anticounterfeiting. Inorg Chem 2023; 62:4147-4156. [PMID: 36848502 DOI: 10.1021/acs.inorgchem.2c04109] [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: 03/01/2023]
Abstract
Mechanoluminescence (ML) materials with tunable emissions can serve in many practical applications; however, their underlying mechanism still needs further clarification. Herein, we developed Eu2+-/Mn2+-/Ce3+-activated Mg3Ca3(PO4)4 (MCP) phosphors and studied their luminescence properties by device fabrication. The intense blue ML is obtained by fabricating MCP:Eu2+ into the polydimethylsiloxane elastomer matrix. The red ML of relatively weak intensity is received in Mn2+ activator, but the ML for the Ce3+ dopant is nearly quenched in the same host. The possible reason is proposed from the analysis of the relative positions between the excitation state and conduction band, together with the trap types. The appropriate location of the excited energy levels in the band gap allows for a larger probability of efficient ML when shallow traps near the excitation states are created synchronously as an effective energy transfer (ET) channel. The concentration-dependent ML for the MCP:Eu2+,Mn2+-based devices indicates that the emitting light color can be tailored, where several ET processes among oxygen vacancies, Eu2+, Ce3+, and Mn2+, occur. The luminescence manipulation with dopants and excitation sources demonstrates the potential applications in visualized multimode anticounterfeiting. These findings open up many possibilities for constructing new ML materials by introducing appropriate traps into the band structures.
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Affiliation(s)
- Jia Zhang
- Physics Department and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligence, Huaiyin Normal University, Huai'an 223300, China
| | - Songsong An
- Physics Department and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligence, Huaiyin Normal University, Huai'an 223300, China
| | - Yuqing Pei
- Physics Department and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligence, Huaiyin Normal University, Huai'an 223300, China
| | - Yining Zhang
- Physics Department and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligence, Huaiyin Normal University, Huai'an 223300, China
| | - Jiajun Chen
- Physics Department and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligence, Huaiyin Normal University, Huai'an 223300, China
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Banerjee D, Kumar Kar A. Structural strategy to enhance the quantum and photocatalytic efficiency of ZnO quantum dots by incorporation of interface states. J Photochem Photobiol A Chem 2023; 437:114500. [DOI: 10.1016/j.jphotochem.2022.114500] [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: 12/23/2022]
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Devi P, Verma R, Singh JP. Advancement in electrochemical, photocatalytic, and photoelectrochemical CO2 reduction: Recent progress in the role of oxygen vacancies in catalyst design. J CO2 UTIL 2022. [DOI: 10.1016/j.jcou.2022.102211] [Citation(s) in RCA: 1] [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] [Indexed: 11/28/2022]
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Sarkar S, Debnath SK, Srivastava R, Kulkarni AR. Continuous flow scale-up of biofunctionalized defective ZnO quantum dots: A safer inorganic ingredient for skin UV protection. Acta Biomater 2022; 147:377-390. [PMID: 35609802 DOI: 10.1016/j.actbio.2022.05.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 05/11/2022] [Accepted: 05/17/2022] [Indexed: 11/01/2022]
Abstract
The versatility of ZnO quantum dots (QDs) exhibiting size-tunable visible photoluminescence has propelled them to the forefront of leading-edge innovations in healthcare. At the nano-bio interface, enhancing the singly-ionized oxygen vacancy defects (VO•) through holistic, sustainable synthesis protocols driven by the synergistic influence of QDs' nucleation-growth kinetics has implications on their bioactivity, physiochemical, and optical performance. Recently, robust continuous flow platforms have transcended the conventional batch reactors by alleviating the concerns of "hot-spot" formation due to inhomogeneous heat distribution, acute energy consumption, poor quality, and yield. However, complexities exist in translating batch chemistries into flow processes. Here, a unique, rationally designed continuous flow synthesis of luminescent defect-engineered ZnO QDs (E-QDs) via helical-reactor assembly that can adequately synthesize on a large scale is reported. The crux of this lies in the amalgamation of "green chemistry" and flow synthesis, which results in Lamer-mechanism mediated monodispersed E-QDs demonstrating high photoluminescence quantum yield (PLQY) of 89% under an accurately regulated synthesis environment. Process intensification corroborated that the bio-stable E-QDs manifested admirable photostability, broad-spectrum UV-shielding (400-250 nm), colloidal stability, in vitro biocompatibility against L929 and HaCaT cells, and antioxidant activity. These attributes were better compared to the commercial ZnO nanoparticles (ZnOC-NPs) used for skin UV protection. Delving deeper, the main drivers for the high density of intrinsic VO• formation (Iv/Io∼42.5) were revealed to be the reactor's hydrodynamic performance and the improvised heating rate (2.5°C/sec). Hence, these E-QDs have potential as a new, safe, and economical multifunctional active ingredient for skin UV protection and antioxidants for treating ROS-mediated disorders. STATEMENT OF SIGNIFICANCE: UV filters exhibiting questionable UV-attenuation efficacy and phototoxicity are significant impediments to the healthcare industry emphasizing skin cancer prevention. Although least explored, VO•-governed aberrant photoactive, biological, and surface-reactive qualities of engineered ZnO QDs (E-QDs) have created ample room to investigate these hallmarks for skin UV protection. However, the bottlenecks in stereotypical ZnO QDs production confined by inefficient process control are annihilated by continuous flow strategies. Herein, the high-throughput continuous flow helical reactor assembly was designed and fabricated to successfully showcase optimized transport properties, reproducibility, yield, and quality E-QDs. Anticipating a skyrocketing demand for E-QDs as bioactive-sunscreen components, the comprehensive investigation has demonstrated unprecedented biofunctionality and ROS-scavenging behaviour, even upon UVR exposure, contrary to the traditional nanoparticulate ZnO UV filters.
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Tuckute S, Varnagiris S, Urbonavicius M, Demikyte E, Bockute K, Lelis M. Structure and Photocatalytic Activity of Copper and Carbon-Doped Metallic Zn Phase-Rich ZnO Oxide Films. Catalysts 2022; 12:60. [DOI: 10.3390/catal12010060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
ZnO is one of the most important industrial metal oxide semiconductors. However, in order to fully realise its potential, the electronic structure of ZnO has to be modified to better fit the needs of specific fields. Recent studies demonstrated that reactive magnetron sputtering under Zn-rich conditions promotes the formation of intrinsic ZnO defects and allows the deposition of metallic Zn phase-rich ZnO films. In photocatalytic efficiency tests these films were superior to traditional ZnO oxide, therefore, the purposeful formation of intrinsic ZnO defects, namely Zn interstitials and oxygen vacancies, can be considered as advantageous self-doping. Considering that such self-doped ZnO remains a semiconductor, the natural question is if it is possible to further improve its properties by adding extrinsic dopants. Accordingly, in the current study, the metallic Zn phase-rich ZnO oxide film formation process (reactive magnetron sputtering) was supplemented by simultaneous sputtering of copper or carbon. Effects of the selected dopants on the structure of self-doped ZnO were investigated by X-ray diffractometer, scanning electron microscope, X-ray photoelectron spectroscope and photoluminescence techniques. Meanwhile, its effect on photocatalytic activity was estimated by visible light activated bleaching of Methylene Blue. It was observed that both dopants modify the microstructure of the films, but only carbon has a positive effect on photocatalytic efficiency.
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Zhang Y, Liu B, Liu Z, Li J. Research progress in synthesis and biological application of quantum dots. NEW J CHEM 2022. [DOI: 10.1039/d2nj02603a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Quantum dots are an excellent choice for biomedical applications due to their special optical properties and quantum confinement effects. This paper reviews the research and application progress of several quantum...
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10
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Ansari SA, Manjunatha C, Parveen N, Shivaraj BW, Hari Krishna R. Mechanistic insights into defect chemistry and tailored photoluminescence and photocatalytic properties of aliovalent cation substituted Zn 0.94M 0.06-xLi xO (M: Fe 3+, Al 3+, Cr 3+) nanoparticles. Dalton Trans 2021; 50:14891-14907. [PMID: 34607338 DOI: 10.1039/d1dt01706c] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, we demonstrate the microwave assisted solution combustion synthesis of aliovalent cation substituted Zn0.94M0.06-xLixO (M: Fe3+, Al3+, Cr3+) nanoparticles. The structural features, photoluminescence and photocatalytic properties were characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and UV-visible and photoluminescence (PL) techniques. We have introduced aliovalent cations such as reducible Fe3+, stable Al3+ and oxidisable Cr3+ ions into ZnO and investigated its structural and optical properties. The charge balance and defect stoichiometric composition of ZnO were also studied by co-doping with Li+ ions. By understanding the photoluminescence and photocatalytic activity of doped and co-doped ZnO nanoparticles, the defect chemistry of ZnO is explained in detail. The photocatalytic efficiency of various doped and co-doped ZnO catalysts was compared with respect to the degradation of rhodamine B dye. Among them, the CZO, AZO and L3AZO catalysts showed enhanced photo-degradation efficiencies of 98.1%, 97.6% and 96.6%, respectively, which are high as compared to that of ZnO (89%). This work presents a novel and straightforward, low-cost, tunable and scalable fabrication protocol for highly efficient ZnO-based photocatalysts for practical applications.
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Affiliation(s)
- Sajid Ali Ansari
- Department of Physics, College of Science, King Faisal University, P.O. Box 400, Hofuf, Al-Ahsa 31982, Saudi Arabia.
| | - C Manjunatha
- Department of Chemistry, RV College of Engineering, Bengaluru, 560059, India. .,Centre for Hydrogen and Green Technology Research (CH2GTR), RV College of Engineering, Bengaluru, 560059, India
| | - Nazish Parveen
- Department of Chemistry, College of Science, King Faisal University, P.O. Box 380, Hofuf, Al-Ahsa 31982, Saudi Arabia
| | - B W Shivaraj
- Department of Mechanical Engineering, RV College of Engineering, Bengaluru, 560059, India
| | - R Hari Krishna
- Department of Chemistry, MS Ramaiah Institute of Technology, Bengaluru, 560054, India.
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12
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Hsiao PH, Wei TC, Chen CY. Stability improvement of Cu(ii)-doped ZnS/ZnO photodetectors prepared with a facile solution-processing method. Inorg Chem Front 2021. [DOI: 10.1039/d0qi00937g] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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
The solution-processed growth of Cu2+ doped ZnS as protective coatings on ZnO nanorods with improved photoresponsivity and stability was presented.
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Affiliation(s)
- Po-Hsuan Hsiao
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Ta-Cheng Wei
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Chia-Yun Chen
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center
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Long Z, Zhang W, Tian J, Chen G, Liu Y, Liu R. Recent research on the luminous mechanism, synthetic strategies, and applications of CuInS2 quantum dots. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01228a] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We discuss the synthesis and luminescence mechanisms of CuInS2 QDs, the strategies to improve their luminous performance and their potential application in light-emitting devices, solar energy conversion, and the biomedical field.
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Affiliation(s)
- Zhiwei Long
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Wenda Zhang
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Junhang Tian
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Guantong Chen
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Yuanhong Liu
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
| | - Ronghui Liu
- National Engineering Research Center for Rare Earth Materials
- General Research Institute for Nonferrous Metals
- Grirem Advanced Materials Co. Ltd
- Beijing
- P. R China
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Sazonov R, Kholodnaya G, Ponomarev D, Zhuravlev M, Pyatkov I, Konusov F, Lapteva O, Gadirov R. Pulsed Plasma-Chemical Modification of SiO 2 Nanopowder by Zn xO y Nanoparticles. Int J Nanosci 2020. [DOI: 10.1142/s0219581x21500058] [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: 11/18/2022]
Abstract
This work presents the results of pulsed plasma-chemical modification of silicon dioxide nanopowder with zinc oxide nanoparticles (ZnO@SiO2). The obtained ZnO@SiO2 powders were characterized by transmission electron microscopy (TEM) and X-ray phase analysis. The size of the synthesized particles was in the range of 20–100[Formula: see text]nm. The photocatalytic characteristics of ZnO@SiO2 were studied. When exposed to ultraviolet radiation, the methylene blue (MB) decomposes efficiently. Two samples characterized by the content of silicon tetrachloride in the initial mixture were synthesized. The band gap estimated from the absorption spectra calculated from the diffuse reflectance spectra for these samples was 2.4[Formula: see text]eV and 2.95[Formula: see text]eV for indirect transitions and 3.03[Formula: see text]eV and 3.24[Formula: see text]eV for direct allowed transitions.
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Affiliation(s)
- Roman Sazonov
- Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028, Russia
| | | | - Denis Ponomarev
- Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028, Russia
| | | | - Igor Pyatkov
- Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028, Russia
| | - Fedor Konusov
- Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028, Russia
| | - Olga Lapteva
- Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028, Russia
| | - Ruslan Gadirov
- Siberian Physical-Technical Institute, Tomsk State University, 1 Novosobornaya Square, Tomsk 634050, Russia
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Kwon JB, Kim SW, Kang BH, Yeom SH, Lee WH, Kwon DH, Lee JS, Kang SW. Air-stable and ultrasensitive solution-cast SWIR photodetectors utilizing modified core/shell colloidal quantum dots. Nano Converg 2020; 7:28. [PMID: 32803407 PMCID: PMC7429620 DOI: 10.1186/s40580-020-00238-3] [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] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
InGaAs-based photodetectors have been generally used for detection in the short-wave infrared (SWIR) region. However, the epitaxial process used to grow these materials is expensive; therefore, InGaAs-based photodetectors are limited to space exploration and military applications. Many researchers have expended considerable efforts to address the problem of SWIR photodetector development using lead sulfide (PbS) quantum dots (QDs). Along with their cost-efficient solution processability and flexible substrate compatibility, PbS QDs are highly interesting for the quantum-size-effect tunability of their bandgaps, spectral sensitivities, and wide absorption ranges. However, the performance of PbS QD-based SWIR photodetectors is limited owing to inefficient carrier transfer and low photo and thermal stabilities. In this study, a simple method is proposed to overcome these problems by incorporating CdS in PbS QD shells to provide efficient carrier transfer and enhance the long-term stability of SWIR photodetectors against oxidation. The SWIR photodetectors fabricated using thick-shell PbS/CdS QDs exhibited a high on/off (light/dark) ratio of 11.25 and a high detectivity of 4.0 × 1012 Jones, which represents a greater than 10 times improvement in these properties relative to those of PbS QDs. Moreover, the lifetimes of thick-shell PbS/CdS QD-based SWIR photodetectors were significantly improved owing to the self-passivation of QD surfaces.
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Affiliation(s)
- Jin-Beom Kwon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Daegu, 702-701, Republic of Korea
| | - Sae-Wan Kim
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Daegu, 702-701, Republic of Korea
| | - Byoung-Ho Kang
- Advanced Semiconductor Research Center, Gumi Electronics and Information Technology Research Institute (GERI), Gumi, 39253, Republic of Korea
| | - Se-Hyuk Yeom
- Advanced Semiconductor Research Center, Gumi Electronics and Information Technology Research Institute (GERI), Gumi, 39253, Republic of Korea
| | - Wang-Hoon Lee
- Advanced Semiconductor Research Center, Gumi Electronics and Information Technology Research Institute (GERI), Gumi, 39253, Republic of Korea
| | - Dae-Hyuk Kwon
- Department of Electronic Engineering, Kyungil University, Hayang-up, 712-702, Gyeongsang buk-do, Republic of Korea
| | - Jae-Sung Lee
- Advanced Semiconductor Research Center, Gumi Electronics and Information Technology Research Institute (GERI), Gumi, 39253, Republic of Korea.
| | - Shin-Won Kang
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Daegu, 702-701, Republic of Korea.
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Panatarani C, Faizal F, Florena FF, Jumhur D, Made Joni I. The effects of divalent and trivalent dopants on the luminescence properties of ZnO fine particle with oxygen vacancies. ADV POWDER TECHNOL 2020. [DOI: 10.1016/j.apt.2020.04.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Costa WC, Sandri C, de Quadros S, Silva AL, Eccher J, Zimmermann LM, Mora JR, Bock H, Bechtold IH. Stabilization of ZnO quantum dots by preferred 1:2 interaction with a liquid crystal molecule. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Shi Q, Ling K, Duan S, Wang X, Xu S, Zhang D, Wang Q, Li S, Zhao L, Wang W. Single-phased emission-tunable Mg and Ce co-doped ZnO quantum dots for white LEDs. Spectrochim Acta A Mol Biomol Spectrosc 2020; 231:118096. [PMID: 32006915 DOI: 10.1016/j.saa.2020.118096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 01/18/2020] [Accepted: 01/21/2020] [Indexed: 06/10/2023]
Abstract
In this study, a simple low-temperature route is presented for the synthesis of Mg and Ce co-doped ZnO quantum dots (QDs). X-ray diffraction, transmission electron microscopy, electron paramagnetic resonance, X-ray photoelectron spectroscopy, UV-vis absorption spectra, and fluorescence measurements were used to characterize the synthesized QDs. The results indicate that the oxygen vacancy concentration could be tuned via Mg and Ce ions doping, which leads to the regulation of luminescence. The visible emission was directly associated with oxygen vacancies, and a blue shift of the visible emission with increasing Ce doping concentration was due to the quantum confinement effect. Finally, we explored the application of Mg and Ce co-doped ZnO QDs by fabricating a white LED device. Notably, the white LED device presents good luminescence properties under a voltage of 3 V and a driven current of 200 mA. The Commission International de l'Eclairage chromaticity, the correlated color temperature, and the color rendering index were determined to be (x = 0.32, y = 0.30), 5733 K, and 81, respectively, which make them potential candidates as single-phased QDs for white light-emitting diodes.
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Affiliation(s)
- Qiang Shi
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China; Shandong Provincial Key Laboratory of Optical Communication Science and Technology, Shandong 252059, China.
| | - Kai Ling
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China
| | - Susu Duan
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China
| | - Xue Wang
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China
| | - Shengxiang Xu
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China
| | - Dong Zhang
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China; Shandong Provincial Key Laboratory of Optical Communication Science and Technology, Shandong 252059, China
| | - Qingru Wang
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China; Shandong Provincial Key Laboratory of Optical Communication Science and Technology, Shandong 252059, China
| | - Shuhong Li
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China; Shandong Provincial Key Laboratory of Optical Communication Science and Technology, Shandong 252059, China
| | - Ling Zhao
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China; Shandong Provincial Key Laboratory of Optical Communication Science and Technology, Shandong 252059, China
| | - Wenjun Wang
- School of Physical Science and Information Technology, Liaocheng University, Shandong 252059, China; Shandong Provincial Key Laboratory of Optical Communication Science and Technology, Shandong 252059, China
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19
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Lei G, Yang S, Cao R, Zhou P, Peng H, Peng R, Zhang X, Yang Y, Li Y, Wang M, He Y, Zhou L, Du J, Du W, Shi Y, Wu H. In Situ Preparation of Amphibious ZnO Quantum Dots with Blue Fluorescence Based on Hyperbranched Polymers and their Application in Bio-Imaging. Polymers (Basel) 2020; 12:E144. [PMID: 31935952 DOI: 10.3390/polym12010144] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 12/24/2019] [Accepted: 01/01/2020] [Indexed: 01/27/2023] Open
Abstract
A new strategy for preparing amphibious ZnO quantum dots (QDs) with blue fluorescence within hyper-branched poly(ethylenimine)s (HPEI) was proposed in this paper. By changing [Zn2+]/[OH-] molar ratio and heating time, ZnO QDs with a quantum yields (QY) of 30% in ethanol were obtained. Benefiting from the amphibious property of HPEI, the ZnO/HPEI nanocomposites in ethanol could be dissolved in chloroform and water, acquiring a QY of 53%, chloroform and 11% in water. By this strategy, the ZnO/HPEI nano-composites could be applied in not only in optoelectronics, but also biomedical fields (such as bio-imaging and gene transfection). The bio-imaging application of water-soluble ZnO/HPEI nanocomposites was investigated and it was found that they could easily be endocytosed by the COS-7 cells, without transfection reagent, and they exhibited excellent biological imaging behavior.
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20
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Lee JS, Kang BH, Kim SW, Kwon JB, Kim OS, Byun YT, Kwon DH, Bae JH, Kang SW. Al atomistic surface modulation on colloidal gradient quantum dots for high-brightness and stable light-emitting devices. Sci Rep 2019; 9:6357. [PMID: 31015572 PMCID: PMC6478915 DOI: 10.1038/s41598-019-42925-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 12/18/2018] [Accepted: 04/10/2019] [Indexed: 11/09/2022] Open
Abstract
Quantum-dot (QD) light-emitting devices (QLEDs) have been attracting considerable attention owing to the unique properties of process, which can control the emission wavelength by controlling the particle size, narrow emission bandwidth, and high brightness. Although there have been rapid advances in terms of luminance and efficiency improvements, the long-term device stability is limited by the low chemical stability and photostability of the QDs against moisture and air. In this study, we report a simple method, which can for enhance the long-term stability of QLEDs against oxidation by inserting Al into the shells of CdSe/ZnS QDs. The Al coated on the ZnS shell of QDs act as a protective layer with Al2O3 owing to photo-oxidation, which can prevents the photodegradation of QD with prolonged irradiation and stabilize the device during a long-term operation. The QLEDs fabricated using CdSe/ZnS/Al QDs exhibited a maximum luminance of 57,580 cd/m2 and current efficiency of 5.8 cd/A, which are significantly more than 1.6 times greater than that of CdSe/ZnS QDs. Moreover, the lifetimes of the CdSe/ZnS/Al-QD-based QLEDs were significantly improved owing to the self-passivation at the QD surfaces.
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Affiliation(s)
- Jae-Sung Lee
- Sensor System Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Byoung-Ho Kang
- Institute of Technology, DONG-A CARBON TECHNOLOGY, 41-3, Gyo 8-Gil, Buksam-eub, Chilgok-gun, Gyeongsangbuk-do, Republic of Korea
| | - Sae-Wan Kim
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Bukgu, 702-701, Daegu, Republic of Korea
| | - Jin-Beom Kwon
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Bukgu, 702-701, Daegu, Republic of Korea
| | - Ok-Sik Kim
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Bukgu, 702-701, Daegu, Republic of Korea
| | - Young Tae Byun
- Sensor System Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Dae-Hyuk Kwon
- Department of Electronic Engineering, Kyungil University, Hayang-up, 712-702, Gyeongsang buk-do, Republic of Korea
| | - Jin-Hyuk Bae
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Bukgu, 702-701, Daegu, Republic of Korea
| | - Shin-Won Kang
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 1370 Sankyuk-dong, Bukgu, 702-701, Daegu, Republic of Korea.
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21
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Huang HB, Yu K, Wang JT, Zhou JR, Li HF, Lü J, Cao R. Controlled growth of ZnS/ZnO heterojunctions on porous biomass carbons via one-step carbothermal reduction enables visible-light-driven photocatalytic H2 production. Inorg Chem Front 2019. [DOI: 10.1039/c9qi00454h] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Controlled growth of ZnS/ZnO heterojunctions on porous biomass carbons has been achieved via a one-step carbothermal reduction strategy.
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Affiliation(s)
- Hai-Bo Huang
- State Key Laboratory of Structural Chemistry
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P.R. China
| | - Kai Yu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation
- College of Resources and Environment
- Fujian Agriculture and Forestry University
- Fuzhou 350002
- P.R. China
| | - Jun-Tao Wang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation
- College of Resources and Environment
- Fujian Agriculture and Forestry University
- Fuzhou 350002
- P.R. China
| | - Jun-Ru Zhou
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation
- College of Resources and Environment
- Fujian Agriculture and Forestry University
- Fuzhou 350002
- P.R. China
| | - Hong-Fang Li
- State Key Laboratory of Structural Chemistry
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P.R. China
| | - Jian Lü
- State Key Laboratory of Structural Chemistry
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P.R. China
| | - Rong Cao
- State Key Laboratory of Structural Chemistry
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou 350002
- P.R. China
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22
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Qi L, Sun B, Wang W, Zhang J, Yang H, Qi Y. Microstructure of oxygen-deficient annealing-induced non-polar ZnO films with extremely low electrical resistivity. CrystEngComm 2019. [DOI: 10.1039/c8ce01794h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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
The influence of oxygen vacancy mediation on the microstructure of post-annealed non-polar ZnO films has been investigated.
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Affiliation(s)
- Lin Qi
- Institute of Materials Physics and Chemistry
- School of Materials Science and Engineering
- Northeastern University
- Shenyang
- PR China
| | - Benzhe Sun
- Institute of Materials Physics and Chemistry
- School of Materials Science and Engineering
- Northeastern University
- Shenyang
- PR China
| | - Weizhen Wang
- Institute of Materials Physics and Chemistry
- School of Materials Science and Engineering
- Northeastern University
- Shenyang
- PR China
| | - Jian Zhang
- Institute of Materials Physics and Chemistry
- School of Materials Science and Engineering
- Northeastern University
- Shenyang
- PR China
| | - Huazhe Yang
- Department of Biophysics
- School of Fundamental Science
- China Medical University
- Shenyang 110122
- China
| | - Yang Qi
- Institute of Materials Physics and Chemistry
- School of Materials Science and Engineering
- Northeastern University
- Shenyang
- PR China
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23
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Martínez-Carmona M, Gun'ko Y, Vallet-Regí M. ZnO Nanostructures for Drug Delivery and Theranostic Applications. Nanomaterials (Basel) 2018; 8:E268. [PMID: 29690644 PMCID: PMC5923598 DOI: 10.3390/nano8040268] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 01/19/2023]
Abstract
In the last two decades, zinc oxide (ZnO) semiconductor Quantum dots (QDs) have been shown to have fantastic luminescent properties, which together with their low-cost, low-toxicity and biocompatibility have turned these nanomaterials into one of the main candidates for bio-imaging. The discovery of other desirable traits such as their ability to produce destructive reactive oxygen species (ROS), high catalytic efficiency, strong adsorption capability and high isoelectric point, also make them promising nanomaterials for therapeutic and diagnostic functions. Herein, we review the recent progress on the use of ZnO based nanoplatforms in drug delivery and theranostic in several diseases such as bacterial infection and cancer.
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Affiliation(s)
- Marina Martínez-Carmona
- School of Chemistry and CRANN, Trinity College, The University of Dublin, Dublin 2, Ireland.
| | - Yurii Gun'ko
- School of Chemistry and CRANN, Trinity College, The University of Dublin, Dublin 2, Ireland.
| | - María Vallet-Regí
- Department Chemistry in Pharmaceutical Sciences, School of Pharmacy , Universidad Complutense de Madrid, Instituto de Investigación Sanitaria Hospital 12 de Octubre i+12, 28040 Madrid, Spain.
- Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Avenida Monforte de Lemos, 3-5, 28029 Madrid, Spain.
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24
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Dixit T, Palani IA, Singh V. Insights into non-noble metal based nanophotonics: exploration of Cr-coated ZnO nanorods for optoelectronic applications. RSC Adv 2018; 8:6820-6833. [PMID: 35540357 PMCID: PMC9078300 DOI: 10.1039/c7ra13174g] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [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: 12/09/2017] [Accepted: 01/31/2018] [Indexed: 11/21/2022] Open
Abstract
Herein, the room temperature photoluminescence and Raman spectra of hydrothermally grown ZnO nanorods coated with Cr are investigated for optoelectronic applications. A thorough examination of the photoluminescence spectra of Cr coated ZnO nanorods showed the suppression of deep level emissions by more than twenty five times with Cr coating compared to that of pristine ZnO nanorods. Moreover, the underlying mechanism was proposed and can be attributed to the formation of Schottky contacts between Cr and ZnO resulting in defect passivation, weak exciton–plasmon coupling, enhanced electric field effect and formation of hot carriers due to interband transitions. Interestingly, with the increase in sputtering time, the ratio of the intensities corresponding to the band gap emission and deep level emission was observed to increase from 6.2 to 42.7, suggesting its application for UV only emission. Further, a planar photodetector was fabricated (Ag–ZnO–Ag planar configuration) and it was observed that the dark current value got reduced by more than ten times with Cr coating, thereby opening up its potential for transistor applications. Finally, Cr coated ZnO nanorods were employed for green light sensing. Our results demonstrated that ZnO nanorods decorated with Cr shed light on developing stable and high-efficiency non-noble metal based nanoplasmonic devices such as photodetectors, phototransistors and solar cells. Herein, the room temperature photoluminescence and Raman spectra of hydrothermally grown ZnO nanorods coated with Cr are investigated for optoelectronic applications.![]()
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Affiliation(s)
- Tejendra Dixit
- Molecular and Nanoelectronics Research Group (MNRG)
- Discipline of Electrical Engineering
- IIT Indore
- Indore
- India
| | - I. A. Palani
- Mechatronics and Instrumentation Lab
- Discipline of Mechanical Engineering
- IIT Indore
- Indore
- India
| | - Vipul Singh
- Molecular and Nanoelectronics Research Group (MNRG)
- Discipline of Electrical Engineering
- IIT Indore
- Indore
- India
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25
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Schindler T, Schmutzler T, Schmiele M, Lin W, Segets D, Peukert W, Appavou MS, Kriele A, Gilles R, Unruh T. Changes within the stabilizing layer of ZnO nanoparticles upon washing. J Colloid Interface Sci 2017; 504:356-62. [PMID: 28582753 DOI: 10.1016/j.jcis.2017.05.059] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/17/2017] [Accepted: 05/18/2017] [Indexed: 10/19/2022]
Abstract
ZnO nanoparticles (NPs) are highly relevant for various industrial applications, however, after synthesis of the NPs residual chemicals need to be removed from the colloidal raw product by washing, as they may influence the performance of the final device. In the present study we focus on the effect of washing by antisolvent flocculation with subsequent redispersion of the NPs on the stabilizing acetate shell. Purification of the ZnO nanoparticles is reported to be optimal with respect to zeta potential that has a maximum after one washing cycle. In this work, we will shed light on this observation using small angle X-ray and neutron scattering (SAXS, SANS) by demonstrating that after the first washing cycle the content of acetate in the ligand shell around the ZnO NPs increases. In detail, it was observed that the diffuse acetate shell shrinks to the size of a monolayer upon washing but the acetate content of this monolayer is higher than within the diffuse shell of the particles of the native dispersion. A second washing cycle reduces the acetate concentration within the stabilizing shell and the stability of the dispersion drops accordingly. After another (third) washing cycle strong agglomeration was observed for all investigated samples.
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26
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Zhang C, Zhu F, Xu H, Liu W, Yang L, Wang Z, Ma J, Kang Z, Liu Y. Significant improvement of near-UV electroluminescence from ZnO quantum dot LEDs via coupling with carbon nanodot surface plasmons. Nanoscale 2017; 9:14592-14601. [PMID: 28933500 DOI: 10.1039/c7nr04392a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Short-wavelength LEDs, a hot research topic in modern optoelectronics, have attracted tremendous attention in recent years because of their great application potential in both civil and military domains. Compared to conventional metallic surface-plasmons (SPs), carbon nanodot (CD) SPs with less optical loss and low cost, broader SP resonant frequency and good biocompatibility are expected to provide more prominent luminescence enhancement for light emitters. Herein, SP-enhanced near-UV emission quantum dot LEDs (Q-LED) were fabricated via introducing CDs into p-GaN/Al2O3/ZnO Q-LEDs by optimizing the molar ratio of ZnO quantum dots to CDs and a significant enhancement (∼20-fold) of the near-UV electroluminescence (EL) intensity from the ZnO-based Q-LEDs was achieved. Time-resolved spectroscopy studies reveal that the observed luminescence enhancement arises due to the resonant coupling between ZnO excitons and CD SPs. The current study not only demonstrates a feasible way to acquire near-UV emission from all-inorganic Q-LEDs, but also provides an effective strategy to enhance the EL intensity of these QD light emitters, which can further be extended to other types of light-emitting devices to improve EL efficiency.
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Affiliation(s)
- Cen Zhang
- Centre for Advanced Optoelectronic Functional Materials Research and Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun 130024, China.
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27
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Kaur N, Raj P, Kaur N, Kim DY, Singh N. Supramolecular hybrid of ZnO nanoparticles with benzimidazole based organic ligand for the recognition of Zn 2+ ions in semi-aqueous media. J Photochem Photobiol A Chem 2017; 347:41-8. [DOI: 10.1016/j.jphotochem.2017.07.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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28
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Saravanan K, Jayalakshmi G, Chandra S, Panigrahi BK, Krishnan R, Sundaravel B, Annapoorani S, Shukla DK, Rajput P, Kanjilal D. The influence of carbon concentration on the electronic structure and magnetic properties of carbon implanted ZnO thin films. Phys Chem Chem Phys 2017; 19:13316-13323. [PMID: 28492651 DOI: 10.1039/c7cp01939d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [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
The influence of carbon concentration on the electronic and magnetic properties of C-implanted ZnO thin films has been studied using synchrotron radiation based X-ray absorption spectroscopic techniques and vibrating sample magnetometer measurements. 20 keV carbon ions were implanted in ZnO films with different fluences (2 × 1016, 4 × 1016 and 6 × 1016 ions per cm2). The pristine ZnO film shows diamagnetic behaviour while the C-implanted films exhibit room temperature ferromagnetism. Our first-principles calculations based on density functional theory show an appreciable magnetic moment only when the implanted C atom sits either in the O-site (2 μB) or in the interstitial position (1.88 μB), whereas the C atom in the Zn substitutional position does not possess any magnetic moment. X-ray absorption near edge structure analysis at the O K-edge reveals that the charge transfer from O-2p to the C-defect site causes the ferromagnetism in the C-implanted ZnO film at low fluence. However at high fluence, the implanted C replaces the lattice and produces more Zn vacancies, as evidenced by extended X-ray absorption fine structure studies at the Zn K-edge, which favors the ferromagnetism. The persistence of the implanted carbon and ferromagnetism of the C-implanted ZnO film has also been studied by isothermal annealing at 500 °C and discussed in detail.
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Affiliation(s)
- K Saravanan
- Material Science Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam - 603102, India.
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29
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V LP, Vijayaraghavan R. Chemical manipulation of oxygen vacancy and antibacterial activity in ZnO. Mater Sci Eng C Mater Biol Appl 2017; 77:1027-1034. [PMID: 28531975 DOI: 10.1016/j.msec.2017.03.280] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Revised: 02/12/2017] [Accepted: 03/29/2017] [Indexed: 11/15/2022]
Abstract
Pure and doped ZnO (cation and anion doping) compositions have been designed in order to manipulate oxygen vacancy and antibacterial activity of ZnO. In this connection, we have synthesized and characterized micron sized ZnO, N doped micron sized ZnO, nano ZnO, nano Na and La doped ZnO. The intrinsic vacancies in pure ZnO and the vacancies created by N and Na doping in ZnO have been confirmed by X-ray Photoelectron Spectroscopy(XPS) and Photoluminiscence Spectroscopy(PL). Reactive oxygen species (ROS) such as hydroxyl radicals, superoxide radicals and H2O2 responsible for antibacterial activity have been estimated by PL, UV-Vis spectroscopy and KMnO4 titrations respectively. It was found that nano Na doped ZnO releases highest amount of ROS followed by nano ZnO, micron N doped ZnO while micron ZnO releases the least amount of ROS. The concentration of vacancies follows the same sequence. This illustrates directly the correlation between ROS and oxygen vacancy in well designed pure and doped ZnO. For the first time, material design in terms of cation doping and anion doping to tune oxygen vacancies has been carried out. Interaction energy (Eg), between the bacteria and nanoparticles has been calculated based on Extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) theory and is correlated with antibacterial activity.
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Affiliation(s)
- Lakshmi Prasanna V
- Department of Chemistry, School of Advanced Sciences, VIT University, Vellore 632 014, Tamilnadu, India
| | - Rajagopalan Vijayaraghavan
- Department of Chemistry, School of Advanced Sciences, VIT University, Vellore 632 014, Tamilnadu, India.
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30
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Hassanzadeh J, Khataee A, Mosaei Oskoei Y, Fattahi H, Bagheri N. Selective chemiluminescence method for the determination of trinitrotoluene based on molecularly imprinted polymer-capped ZnO quantum dots. NEW J CHEM 2017. [DOI: 10.1039/c7nj01802a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [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
A novel molecularly imprinted polymer (MIP) based chemiluminescence (CL) assay is described for the determination of TNT in environmental samples.
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Affiliation(s)
- Javad Hassanzadeh
- Research Laboratory of Advanced Water and Wastewater Treatment Processes
- Department of Applied Chemistry
- Faculty of Chemistry
- University of Tabriz
- 51666-16471 Tabriz
| | - Alireza Khataee
- Research Laboratory of Advanced Water and Wastewater Treatment Processes
- Department of Applied Chemistry
- Faculty of Chemistry
- University of Tabriz
- 51666-16471 Tabriz
| | - Yones Mosaei Oskoei
- North-West Institute of Science and Technology
- Malek Ashtar University of Technology
- Urmia 5713616864
- Iran
| | - Hassan Fattahi
- North-West Institute of Science and Technology
- Malek Ashtar University of Technology
- Urmia 5713616864
- Iran
| | - Nafiseh Bagheri
- Department of Chemistry
- Faculty of Science
- Azarbaijan Shahid Madani University
- Tabriz
- Iran
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31
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Adnan RH, Woon KL, Chanlek N, Nakajima H, Majid WHA. Ligand-Stabilized ZnO Quantum Dots: Molecular Dynamics and Experimental Study. Aust J Chem 2017; 70:1110. [DOI: 10.1071/ch17078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Different aminoalcohol ligands, monoethanolamine (MEA), diethanolamine (DEA) and triethanolamine (TEA) were employed to passivate the surface of ZnO quantum dots (ZnO QDs). High-resolution transmission electron microscopy (HRTEM) imaging revealed that the higher branched aminoalcohols produced smaller sized ZnO QDs. The average size for ZnO/MEA, ZnO/DEA, and ZnO/TEA were found to be 3.2, 2.9, and 2.4 nm. TEA ligands were effective in producing stable, monodisperse ZnO QDs compared with DEA and MEA ligands. Molecular dynamics and semi-empirical calculations suggested that TEA and DEA ligands interact strongly with the partial charge of ZnO dangling bonds and have a large molar volume to hinder the diffusion of precursors through the ligands to the surface of ZnO resulting in a smaller particle size as compared with MEA ligands. As the size of ZnO QDs decreases from ZnO/MEA to ZnO/TEA, the absorption edge and emission peak maximum blue-shifts to a shorter wavelength due to the quantum size effect. The bandgap of ZnO/MEA, ZnO/DEA, and ZnO/TEA was determined to be 3.97, 4.07, and 4.23 eV, and the emission peak was found to be 472, 464, and 458 nm when excited using a 325 nm excitation wavelength, respectively.
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32
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Affiliation(s)
- Gaixia Xu
- Key
Laboratory of Optoelectronics Devices and Systems of Ministry of Education/Guangdong
Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, People’s Republic of China
- CINTRA
CNRS/NTU/THALES,
UMI 3288, Research Techno Plaza, 50
Nanyang Drive, Border X Block, Singapore 637553, Singapore
| | - Shuwen Zeng
- School
of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
- CINTRA
CNRS/NTU/THALES,
UMI 3288, Research Techno Plaza, 50
Nanyang Drive, Border X Block, Singapore 637553, Singapore
| | - Butian Zhang
- School
of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | | | - Ken-Tye Yong
- School
of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
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33
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Affiliation(s)
- Qingwei Wang
- Key Laboratory of Preparation and Applications of Environmental Friendly Materials, Jilin Normal University, Ministry of Education, Changchun, China
| | - Jiaqi Jiang
- School of Chemistry, Jilin Normal University, Siping, China
| | - Wei Sui
- School of Chemistry, Jilin Normal University, Siping, China
| | - Xue Lin
- Key Laboratory of Preparation and Applications of Environmental Friendly Materials, Jilin Normal University, Ministry of Education, Changchun, China
| | - Bo Liu
- Key Laboratory of Preparation and Applications of Environmental Friendly Materials, Jilin Normal University, Ministry of Education, Changchun, China
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34
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Dillip GR, Banerjee AN, Anitha VC, Deva Prasad Raju B, Joo SW, Min BK. Oxygen Vacancy-Induced Structural, Optical, and Enhanced Supercapacitive Performance of Zinc Oxide Anchored Graphitic Carbon Nanofiber Hybrid Electrodes. ACS Appl Mater Interfaces 2016; 8:5025-5039. [PMID: 26836110 DOI: 10.1021/acsami.5b12322] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Zinc oxide (ZnO) nanoparticles (NPs) anchored to carbon nanofiber (CNF) hybrids were synthesized using a facile coprecipitation method. This report demonstrates an effective strategy to intrinsically improve the conductivity and supercapacitive performance of the hybrids by inducing oxygen vacancies. Oxygen deficiency-related defect analyses were performed qualitatively as well as quantitatively using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. All of the analyses clearly indicate an increase in oxygen deficiencies in the hybrids with an increase in the vacuum-annealing temperature. The nonstoichiometric oxygen vacancy is mainly induced via the migration of the lattice oxygen into interstitial sites at elevated temperature (300 °C), followed by diffusion into the gaseous phase with further increase in the annealing temperature (600 °C) in an oxygen-deficient atmosphere. This induction of oxygen vacancy is corroborated by diffuse reflectance spectroscopy, which depicts the oxygen-vacancy-induced bandgap narrowing of the ZnO NPs within the hybrids. At a current density of 3 A g(-1), the hybrid electrode exhibited higher energy density (119.85 Wh kg(-1)) and power density (19.225 kW kg(-1)) compared to a control ZnO electrode (48.01 Wh kg(-1) and 17.687 kW kg(-1)). The enhanced supercapacitive performance is mainly ascribed to the good interfacial contact between CNF and ZnO, high oxygen deficiency, and fewer defects in the hybrid. Our results are expected to provide new insights into improving the electrochemical properties of various composites/hybrids.
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35
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Lv Y, Yao W, Zong R, Zhu Y. Fabrication of Wide-Range-Visible Photocatalyst Bi2WO6-x nanoplates via Surface Oxygen Vacancies. Sci Rep 2016; 6:19347. [PMID: 26777609 PMCID: PMC4726091 DOI: 10.1038/srep19347] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [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: 07/06/2015] [Accepted: 12/07/2015] [Indexed: 12/22/2022] Open
Abstract
Bi2WO6 as a high visible-light-driven catalyst has been aroused broad interest. However, it can only be excitated by the light with λ < 450 nm and the solar energy utilization need to be improved. Here, the wide-range-visible photoresponse Bi2WO6-x nanoplates were fabricated by introducing surface oxygen vacancies through the controllable hydrogen reduction method. The visible photoresponse wavelength range is extended from 450 nm to more than 600 nm. In addition, the photocatalytic activity of Bi2WO6-x is also increased and is 2.1 times as high as that of pristine Bi2WO6. The extending of the photoresponse range and the enhancement of the photoactivity both can be attributed to the surface-oxygen-vacancy states. This is because surface-oxygen-vacancy states generated above and partly overlapping of with the valence band (VB) will result in the rising of valence band maximum (VBM), thus broadening the VB width. This approach is proposed to develop many types of wide-range-visible optical materials and to be applicable to many narrow and wide bandgap materials.
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Affiliation(s)
- Yanhui Lv
- Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Tsinghua University, Beijing, 100084, People’s Republic of China
- Key Laboratory of Photochemistry Beijing National Laboratory for Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
| | - Wenqing Yao
- Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Tsinghua University, Beijing, 100084, People’s Republic of China
| | - Ruilong Zong
- Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Tsinghua University, Beijing, 100084, People’s Republic of China
| | - Yongfa Zhu
- Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Tsinghua University, Beijing, 100084, People’s Republic of China
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36
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Kaur N, Singh J, Raj P, Singh N, Singh H, Sharma SK, Kim DY, Kaur N. ZnO decorated with organic nanoparticles based sensor for the ratiometric selective determination of mercury ions. NEW J CHEM 2016. [DOI: 10.1039/c5nj03099d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Fully characterized organic nanoparticles (R1) decorated on the surface of ZnO (N1), used for selective nanomolar determination of mercury ions.
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Affiliation(s)
- Narinder Kaur
- Semiconductor Materials and Device Laboratory
- Department of Semiconductor Science
- Dongguk University-Seoul
- Seoul 100715
- Republic of Korea
| | - Jasminder Singh
- Department of Chemistry
- Indian Institute of Technology (IIT) Ropar
- India
| | - Pushap Raj
- Department of Chemistry
- Indian Institute of Technology (IIT) Ropar
- India
| | - Narinder Singh
- Department of Chemistry
- Indian Institute of Technology (IIT) Ropar
- India
| | - Harpreet Singh
- School of Mechanical
- Materials & Energy Engineering
- Rupnagar
- India
| | - Sanjeev K. Sharma
- Semiconductor Materials and Device Laboratory
- Department of Semiconductor Science
- Dongguk University-Seoul
- Seoul 100715
- Republic of Korea
| | - Deuk Young Kim
- Semiconductor Materials and Device Laboratory
- Department of Semiconductor Science
- Dongguk University-Seoul
- Seoul 100715
- Republic of Korea
| | - Navneet Kaur
- Centre for Nanoscience and Nanotechnology (UIEAST)
- Panjab University
- Chandigarh
- India
- Department of Chemistry
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37
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Li S, Ye S, Liu T, Guo Z, Wang H, Wang D. Dual role of the reactant MOH (M=Li, Na or K) in the growth of ZnO quantum dots under a sol–gel process: promoter and inhibitor. RSC Adv 2016. [DOI: 10.1039/c6ra06660g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
ZnO quantum dots (QDs) with tunable size and photoluminescence can be achieved simply by controlling their growth during the sol–gel synthesis process.
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Affiliation(s)
- Song Li
- School of Materials Science and Engineering
- Tongji University
- Shanghai 201806
- China
| | - Song Ye
- School of Materials Science and Engineering
- Tongji University
- Shanghai 201806
- China
| | - Tianhua Liu
- School of Materials Science and Engineering
- Tongji University
- Shanghai 201806
- China
| | - Zhuang Guo
- School of Materials Science and Engineering
- Tongji University
- Shanghai 201806
- China
| | - Huiyun Wang
- School of Materials Science and Engineering
- Tongji University
- Shanghai 201806
- China
| | - Deping Wang
- School of Materials Science and Engineering
- Tongji University
- Shanghai 201806
- China
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38
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Abstract
AbstractIn sunscreens, ZnO nanoparticles (NPs) are used as inorganic UV filter which have a prominent band edge emission in the UVA region (~385 nm). When applied to biological surface, this highly penetrating UVA emission from ZnO NPs would enhance the generation of reactive oxygen species resulting in oxidative stress. Therefore, the elimination of this harmful UVA emission from ZnO NPs are much sought after for the development of safer sunscreens. In this paper we introduce the use of defect-rich ZnO (D-ZnO) quantum dots (QDs) as a multifunctional active ingredient in sunscreen/cosmetic application. These D-ZnO QDs make use of their defect energy levels to emit in visible region by bypassing their harmful band edge emission at UVA region. The D-ZnO QDs also showed prominent visible luminescence which matches well with the autofluorescence of in vivo human skin. Hence, this visible luminescence could be useful for camouflaging, thereby enabling its potential as a biologically safe active ingredient for both cosmetic and UV screening applications.
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Affiliation(s)
- Adersh Asok
- 1Centre for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Ajit R. Kulkarni
- 2Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Mayuri N. Gandhi
- 1Centre for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076, India
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39
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Abdelmonem AM, Pelaz B, Kantner K, Bigall NC, Del Pino P, Parak WJ. Charge and agglomeration dependent in vitro uptake and cytotoxicity of zinc oxide nanoparticles. J Inorg Biochem 2015; 153:334-338. [PMID: 26387023 DOI: 10.1016/j.jinorgbio.2015.08.029] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [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: 05/21/2015] [Revised: 08/20/2015] [Accepted: 08/28/2015] [Indexed: 01/19/2023]
Abstract
The influence of the surface charge and the state of agglomeration of ZnO nanoparticles on cellular uptake and viability are investigated. For this purpose, ZnO nanoparticles were synthesized by colloidal routes and their physicochemical properties were investigated in detail. Three different surface modifications were investigated, involving coatings with the amphiphilic polymer poly(isobutylene-alt-maleic anhydride)-graft-dodecyl, mercaptoundecanoic acid, and L-arginine, which provide the nanoparticles with either a negative or a positive zeta-potential. The hydrodynamic diameters and zeta-potentials of all three nanoparticle species were investigated at different pH values and NaCl concentrations by means of dynamic light scattering and laser Doppler anemometry, respectively. The three differently modified ZnO nanoparticle species of similar sizes were also investigated in respect to their cellular uptake by 3T3 fibroblasts and HeLa cells, and their effect on cell viability.
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Affiliation(s)
| | - Beatriz Pelaz
- Fachbereich Physik, Philipps Universität Marburg, Marburg, Germany
| | - Karsten Kantner
- Fachbereich Physik, Philipps Universität Marburg, Marburg, Germany
| | - Nadja C Bigall
- Fachbereich Physik, Philipps Universität Marburg, Marburg, Germany
| | | | - Wolfgang J Parak
- Fachbereich Physik, Philipps Universität Marburg, Marburg, Germany; CIC Biomagune, San Sebastian, Spain.
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40
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Asok A, Ghosh S, More PA, Chopade BA, Gandhi MN, Kulkarni AR. Surface defect rich ZnO quantum dots as antioxidants inhibiting α-amylase and α-glucosidase: a potential anti-diabetic nanomedicine. J Mater Chem B 2015; 3:4597-4606. [DOI: 10.1039/c5tb00407a] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The antioxidant and enzyme inhibitory activity of defect rich ZnO quantum dots is reported, which shows potential for developing anti-diabetic nanomedicine.
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Affiliation(s)
- Adersh Asok
- Centre for Research in Nanotechnology and Science
- Indian Institute of Technology Bombay
- Mumbai-400076
- India
| | - Sougata Ghosh
- Institute of Bioinformatics and Biotechnology
- University of Pune
- Pune-411007
- India
| | - Piyush A. More
- Institute of Bioinformatics and Biotechnology
- University of Pune
- Pune-411007
- India
| | - Balu A. Chopade
- Department of Microbiology
- University of Pune
- Pune-411007
- India
| | - Mayuri N. Gandhi
- Centre for Research in Nanotechnology and Science
- Indian Institute of Technology Bombay
- Mumbai-400076
- India
| | - Ajit R. Kulkarni
- Department of Metallurgical Engineering and Materials Science
- Indian Institute of Technology Bombay
- Mumbai-400076
- India
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41
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Saravanan K, Krishnan R, Hsieh SH, Wang HT, Wang YF, Pong WF, Asokan K, Avasthi DK, Kanjilal D. Effect of defects and film thickness on the optical properties of ZnO–Au hybrid films. RSC Adv 2015. [DOI: 10.1039/c5ra02144h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [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] Open
Abstract
Thickness and defects effects on the optical properties of ZnO–Au hybrid films were studied using optical and electronic structural studies.
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Affiliation(s)
- K. Saravanan
- Department of Physics
- Tamkang University
- Tamsui-251
- Taiwan
| | - R. Krishnan
- Materials Science Group
- Indira Gandhi Centre for Atomic Research
- Kalpakkam-603102
- India
| | - S. H. Hsieh
- Department of Physics
- Tamkang University
- Tamsui-251
- Taiwan
| | - H. T. Wang
- Department of Physics
- National Tsing Hua University
- Hsinchu-30013
- Taiwan
| | - Y. F. Wang
- Department of Physics
- Tamkang University
- Tamsui-251
- Taiwan
| | - W. F. Pong
- Department of Physics
- Tamkang University
- Tamsui-251
- Taiwan
| | - K. Asokan
- Materials Science Group
- Inter-University Accelerator Centre
- New Delhi-110067
- India
| | - D. K. Avasthi
- Materials Science Group
- Inter-University Accelerator Centre
- New Delhi-110067
- India
| | - D. Kanjilal
- Materials Science Group
- Inter-University Accelerator Centre
- New Delhi-110067
- India
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42
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Guo DY, Shan CX, Qu SN, Shen DZ. Highly sensitive ultraviolet photodetectors fabricated from ZnO quantum dots/carbon nanodots hybrid films. Sci Rep 2014; 4:7469. [PMID: 25502422 DOI: 10.1038/srep07469] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 11/26/2014] [Indexed: 11/16/2022] Open
Abstract
Ultraviolet photodetectors have been fabricated from ZnO quantum dots/carbon nanodots hybrid films, and the introduction of carbon nanodots improves the performance of the photodetectors greatly. The photodetectors can be used to detect very weak ultraviolet signals (as low as 12 nW/cm2). The detectivity and noise equivalent power of the photodetector can reach 3.1 × 1017 cmHz1/2/W and 7.8 × 10−20 W, respectively, both of which are the best values ever reported for ZnO-based photodetectors. The mechanism for the high sensitivity of the photodetectors has been attributed to the enhanced carrier-separation at the ZnO/C interface.
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43
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Jacobsson TJ, Viarbitskaya S, Mukhtar E, Edvinsson T. A size dependent discontinuous decay rate for the exciton emission in ZnO quantum dots. Phys Chem Chem Phys 2014; 16:13849-57. [PMID: 24658340 DOI: 10.1039/c4cp00254g] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [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
The time resolved UV-fluorescence in ZnO quantum dots has been investigated using femtosecond laser spectroscopy. The measurements were performed as a function of particle size for particles between 3 and 7 nm in diameter, which are in the quantum confined regime. A red shift in the fluorescence maximum is seen while increasing the particle size, which correlates with the shift in band gap due to quantum confinement. The energy difference between the UV-fluorescence and the band gap does, however, increase for the smaller particles. For 3.7 nm particles the fluorescence energy is 100 meV smaller than the band gap energy, whereas it is only 20 meV smaller for the largest particles. This indicates a stabilization of the excitons in the smallest particles. The lifetime of the UV fluorescence is in the picosecond time scale and interestingly, it is discontinuous with respect to particle size. For the smallest particles, the exciton emission life time reaches 30 ps, which is three times longer than that for the largest particles. This demonstrates a transition between two different mechanisms for the UV-fluorescence. We suggest that this is an effect of surface trapping and stabilization of the excitons occurring in the smallest particles but not in the larger ones. We also discuss the time scale limit for slowed hot carrier dynamics in ensembles of quantum confined ZnO particles.
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Affiliation(s)
- T Jesper Jacobsson
- Department of Chemistry - Ångström Laboratry, Uppsala University, Box 538, 75121 Uppsala, Sweden.
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44
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Biroju RK, Giri PK, Dhara S, Imakita K, Fujii M. Graphene-assisted controlled growth of highly aligned ZnO nanorods and nanoribbons: growth mechanism and photoluminescence properties. ACS Appl Mater Interfaces 2014; 6:377-387. [PMID: 24367888 DOI: 10.1021/am404411c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We demonstrate graphene-assisted controlled fabrication of various ZnO 1D nanostructures on the SiO2/graphene substrate at a low temperature (540 °C) and elucidate the growth mechanism. Monolayer and a few layer graphene prepared by chemical vapor deposition (CVD) and subsequently coated with a thin Au layer followed by rapid thermal annealing is shown to result in highly aligned wurtzite ZnO nanorods (NRs) with clear hexagonal facets. On the other hand, direct growth on CVD graphene without a Au catalyst layer resulted in a randomly oriented growth of dense ZnO nanoribbons (NRBs). The role of in-plane defects and preferential clustering of Au atoms on the defect sites of graphene on the growth of highly aligned ZnO NRs/nanowires (NWs) on graphene was established from micro-Raman and high-resolution transmission electron microscopy analyses. Further, we demonstrate strong UV and visible photoluminescence (PL) from the as-grown and post-growth annealed ZnO NRs, NWs, and NRBs, and the origin of the PL emission is correlated well with the X-ray photoelectron spectroscopy analysis. Our results hint toward an epitaxial growth of aligned ZnO NRs on graphene by a vapor-liquid-solid mechanism and establish the importance of defect engineering in graphene for controlled fabrication of graphene-semiconductor NW hybrids with improved optoelectronic functionalities.
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Affiliation(s)
- Ravi K Biroju
- Centre for Nanotechnology, Indian Institute of Technology Guwahati , Guwahati 781039, India
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45
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Huang JJ, Ye YB, Lei ZQ, Ye XJ, Rong MZ, Zhang MQ. Highly luminescent and transparent ZnO quantum dots–epoxy composite used for white light emitting diodes. Phys Chem Chem Phys 2014; 16:5480-4. [DOI: 10.1039/c3cp55098b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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46
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Zhao D, Song H, Hao L, Liu X, Zhang L, Lv Y. Luminescent ZnO quantum dots for sensitive and selective detection of dopamine. Talanta 2013; 107:133-9. [PMID: 23598203 DOI: 10.1016/j.talanta.2013.01.006] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 01/02/2013] [Accepted: 01/04/2013] [Indexed: 12/23/2022]
Abstract
Water-soluble and luminescent ZnO quantum dots (QDs) capped by (3-aminopropyl) triethoxysilane (APTES) are environment-friendly with strong photoluminescence (max. wavelength: 530 nm). Interestingly, it was found that the fluorescence could be quenched by dopamine (DA) directly. On the basis of above, a novel ZnO QDs based fluorescent probe has been successfully designed to detect DA with high selectivity and sensitivity. Moreover, the possible fluorescence quenching mechanism was proposed, which showed that the quenching effect may be caused by the electron transfer from ZnO QDs to oxidized dopamine-quinone. Under optimum conditions, the relative fluorescence intensity was linearly proportional to the concentration of DA within the range from 0.05 to 10 μM, with the detection limit down to 12 nM (n=3). Also, the selectivity experiment indicated the probe had a high selectivity for DA over a number of possible interfering species. Finally, this method was successfully used to detect DA in serum samples with quantitative recoveries (99-110%). With excellent selectivity and high sensitivity, it is believed that the ZnO QDs based fluorescent probe has a potential for the practical application in clinical analysis.
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Affiliation(s)
- Di Zhao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
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47
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Lv Y, Yao W, Ma X, Pan C, Zong R, Zhu Y. The surface oxygen vacancy induced visible activity and enhanced UV activity of a ZnO1−x photocatalyst. Catal Sci Technol 2013. [DOI: 10.1039/c3cy00369h] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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