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Li Z, Chen P, Feng J, Zhao M, Zhao Z, Zhang Y, Xu X, Huang H, Zou Z, Li Z. Lattice Oxygen in Photocatalytic Gas-Solid Reactions: Participator vs. Dominator. Angew Chem Int Ed Engl 2024; 63:e202409876. [PMID: 38923765 DOI: 10.1002/anie.202409876] [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: 05/25/2024] [Revised: 06/19/2024] [Accepted: 06/24/2024] [Indexed: 06/28/2024]
Abstract
Lattice-oxygen activation has emerged as a popular strategy for optimizing the performance and selectivity of oxide-based thermocatalysis and electrolysis. However, the significance of lattice oxygen in oxide photocatalysts has been ignored, particularly in gas-solid reactions. Here, using methane oxidation over a Ru1@ZnO single-atom photocatalyst as the prototypical reaction and via 18O isotope labelling techniques, we found that lattice oxygen can directly participate in gas-solid reactions. Lattice oxygen played a dominant role in the photocatalytic reaction, as determined by estimating the kinetic constants in the initial stage. Furthermore, we discovered that dynamic diffusion between O2 and lattice oxygen proceeded even in the absence of targeted reactants. Finally, single-atom Ru can facilitate the activation of adsorbed O2 and the subsequent regeneration of consumed lattice oxygen, thus ensuring high catalyst activity and stability. The results provide guidance for next-generation oxide photocatalysts with improved activities and selectivities.
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Affiliation(s)
- Zhonghua Li
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
- Jiangsu Key Laboratory for Nano Technology, Nanjing University, Nanjing, 210093, China
| | - Ping Chen
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Jianyong Feng
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Minyue Zhao
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Zongyan Zhao
- Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China
| | - Yuanming Zhang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Xiaoming Xu
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Huiting Huang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Zhigang Zou
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
- Jiangsu Key Laboratory for Nano Technology, Nanjing University, Nanjing, 210093, China
| | - Zhaosheng Li
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
- Jiangsu Key Laboratory for Nano Technology, Nanjing University, Nanjing, 210093, China
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Cao J, Lin Y, Zhou T, Wang W, Zhang Q, Pan B, Jiang W. Molecular oxygen-assisted in defect-rich ZnO for catalytic depolymerization of polyethylene terephthalate. iScience 2023; 26:107492. [PMID: 37609634 PMCID: PMC10440522 DOI: 10.1016/j.isci.2023.107492] [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: 03/07/2023] [Revised: 03/22/2023] [Accepted: 07/23/2023] [Indexed: 08/24/2023] Open
Abstract
Polyethylene terephthalate (PET) is the most produced polyester plastic; its waste has a disruptive impact on the environment and ecosystem. Here, we report a catalytic depolymerization of PET into bis(2-hydroxyethyl) terephthalate (BHET) using molecule oxygen (O2)-assisted in defect-rich ZnO. At air, the PET conversion rate, the BHET yield, and the space-time yield are 3.5, 10.6, and 10.6 times higher than those in nitrogen, respectively. Combining structural characterization with the results of DFT calculations, we conclude that the (100) facet of defect-rich ZnO nanosheets conducive to the formation of reactive oxygen species (∗O2-) and Zn defect, promotes the PET breakage of the ester bond and thus complete the depolymerization processed. This approach demonstrates a sustainable route for PET depolymerization by molecule-assisted defect engineering.
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Affiliation(s)
- Jingjing Cao
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Organic Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Yuheng Lin
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Organic Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Tianpeng Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Organic Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Wei Wang
- Department of Chemistry and Centre for Pharmacy, University of Bergen, 5007 Bergen, Norway
| | - Quanxing Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Organic Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Organic Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Wei Jiang
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Organic Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
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Electrochemical Immunosensor for the Determination of Antibodies against Prostate-Specific Antigen Based on ZnO Nanostructures. Int J Mol Sci 2023; 24:ijms24065803. [PMID: 36982877 PMCID: PMC10052783 DOI: 10.3390/ijms24065803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/07/2023] [Accepted: 03/14/2023] [Indexed: 03/22/2023] Open
Abstract
In this study, ZnO nanostructures with different types of morphologies and particle sizes were evaluated and applied for the development of an immunosensor. The first material was composed of spherical, polydisperse nanostructures with a particle size in the range of 10–160 nm. The second was made up of more compact rod-like spherical nanostructures with the diameter of these rods in the range of 50–400 nm, and approximately 98% of the particles were in the range of 20–70 nm. The last sample of ZnO was made up of rod-shaped particles with a diameter of 10–80 nm. These ZnO nanostructures were mixed with Nafion solution and drop-casted onto screen-printed carbon electrodes (SPCE), followed by a further immobilization of the prostate-specific antigen (PSA). The affinity interaction of PSA with monoclonal antibodies against PSA (anti-PSA) was evaluated using the differential pulse voltammetry technique. The limit of detection and limit of quantification of anti-PSA were determined as 1.35 nM and 4.08 nM for compact rod-shaped spherical ZnO nanostructures, and 2.36 nM and 7.15 nM for rod-shaped ZnO nanostructures, respectively.
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Banerjee D, Banerjee P, Kar AK. Structure-correlated excitation wavelength-dependent optical properties of ZnO nanostructures for multifunctional applications. NEW J CHEM 2023. [DOI: 10.1039/d2nj04571k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Excitation wavelength-dependent visible emissions from ZnO nanostructures demonstrate that defect states are insufficient to explain their optical properties.
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Affiliation(s)
- Dhritiman Banerjee
- Micro and Nano Science Laboratory, Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, 826004, India
| | - Payal Banerjee
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan, Republic of China
| | - Asit Kumar Kar
- Micro and Nano Science Laboratory, Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, 826004, India
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Photocatalytic Performance of Undoped and Al-Doped ZnO Nanoparticles in the Degradation of Rhodamine B under UV-Visible Light:The Role of Defects and Morphology. Int J Mol Sci 2022; 23:ijms232415459. [PMID: 36555102 PMCID: PMC9779551 DOI: 10.3390/ijms232415459] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
Quasi-spherical undoped ZnO and Al-doped ZnO nanoparticles with different aluminum content, ranging from 0.5 to 5 at% of Al with respect to Zn, were synthesized. These nanoparticles were evaluated as photocatalysts in the photodegradation of the Rhodamine B (RhB) dye aqueous solution under UV-visible light irradiation. The undoped ZnO nanopowder annealed at 400 °C resulted in the highest degradation efficiency of ca. 81% after 4 h under green light irradiation (525 nm), in the presence of 5 mg of catalyst. The samples were characterized using ICP-OES, PXRD, TEM, FT-IR, 27Al-MAS NMR, UV-Vis and steady-state PL. The effect of Al-doping on the phase structure, shape and particle size was also investigated. Additional information arose from the annealed nanomaterials under dynamic N2 at different temperatures (400 and 550 °C). The position of aluminum in the ZnO lattice was identified by means of 27Al-MAS NMR. FT-IR gave further information about the type of tetrahedral sites occupied by aluminum. Photoluminescence showed that the insertion of dopant increases the oxygen vacancies reducing the peroxide-like species responsible for photocatalysis. The annealing temperature helps increase the number of red-emitting centers up to 400 °C, while at 550 °C, the photocatalytic performance drops due to the aggregation tendency.
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Picasso C, Salinas Y, Brüggemann O, Scharber MC, Sariciftci NS, Cardozo ODF, Rodrigues ES, Silva MS, Stingl A, Farias PMA. Lanthanide (Eu, Tb, La)-Doped ZnO Nanoparticles Synthesized Using Whey as an Eco-Friendly Chelating Agent. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2265. [PMID: 35808100 PMCID: PMC9268008 DOI: 10.3390/nano12132265] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/11/2022] [Accepted: 06/24/2022] [Indexed: 02/04/2023]
Abstract
Strategies for production and use of nanomaterials have rapidly moved towards safety and sustainability. Beyond these requirements, the novel routes must prove to be able to preserve and even improve the performance of the resulting nanomaterials. Increasing demand of high-performance nanomaterials is mostly related to electronic components, solar energy harvesting devices, pharmaceutical industries, biosensors, and photocatalysis. Among nanomaterials, Zinc oxide (ZnO) is of special interest, mainly due to its environmental compatibility and vast myriad of possibilities related to the tuning and the enhancement of ZnO properties. Doping plays a crucial role in this scenario. In this work we report and discuss the properties of undoped ZnO as well as lanthanide (Eu, Tb, and La)-doped ZnO nanoparticles obtained by using whey, a by-product of milk processing, as a chelating agent, without using citrate nor any other chelators. The route showed to be very effective and feasible for the affordable large-scale production of both pristine and doped ZnO nanoparticles in powder form.
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Affiliation(s)
- Carolina Picasso
- Institute of Inorganic Chemistry, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria;
| | - Yolanda Salinas
- Institute of Polymer Chemistry (ICP), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria;
| | - Oliver Brüggemann
- Institute of Polymer Chemistry (ICP), Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria;
| | - Markus Clark Scharber
- Linz Institute for Organic Solar Cells (LIOS), Physical Chemistry Institute, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria; (M.C.S.); (N.S.S.)
| | - Niyazi Serdar Sariciftci
- Linz Institute for Organic Solar Cells (LIOS), Physical Chemistry Institute, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria; (M.C.S.); (N.S.S.)
| | - Olavo D. F. Cardozo
- Post-Graduate Program on Electrical Engineering, Federal University of Pernambuco, Cidade Universitaria, Recife 50670-901, Brazil;
- Phornano Holding GmbH, Kleinengersdorferstrasse 24, 2100 Korneuburg, Austria;
| | - Eriverton S. Rodrigues
- Post-Graduate Program on Material Sciences, Federal University of Pernambuco, Cidade Universitaria, Recife 50670-901, Brazil;
- Federal Institute of Education, Science and Technology of Sertão Pernambucano, Salgueiro 56000-000, Brazil;
| | - Marcelo S. Silva
- Federal Institute of Education, Science and Technology of Sertão Pernambucano, Salgueiro 56000-000, Brazil;
| | - Andreas Stingl
- Phornano Holding GmbH, Kleinengersdorferstrasse 24, 2100 Korneuburg, Austria;
| | - Patricia M. A. Farias
- Post-Graduate Program on Material Sciences, Federal University of Pernambuco, Cidade Universitaria, Recife 50670-901, Brazil;
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Free-Standing ZnO:Mo Nanorods Exposed to Hydrogen or Oxygen Plasma: Influence on the Intrinsic and Extrinsic Defect States. MATERIALS 2022; 15:ma15062261. [PMID: 35329712 PMCID: PMC8949513 DOI: 10.3390/ma15062261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/10/2022] [Accepted: 03/15/2022] [Indexed: 01/25/2023]
Abstract
Cationic doping of ZnO nanorods has gained increased interest as it can lead to the production of materials with improved luminescent properties, electrical conductivity and stability. We report on various Mo-doped ZnO powders of nanorods synthesized by the hydrothermal growth method. Further annealing or/and cold hydrogen or oxygen plasma modification was applied. The atomic structure of the as-grown and plasma-modified rods was characterized by X-ray diffraction. To identify any possible changes in morphology, scanning electron microscopy was used. Paramagnetic point defects were investigated by electron paramagnetic resonance. In particular, two new types of defects were initiated by the plasma treatment. Their appearance was explained, and corresponding mechanisms were proposed. The changes in the luminescence and scintillation properties were characterized by photo- and radioluminescence, respectively. Charge trapping phenomena were studied by thermally stimulated luminescence. Cold plasma treatment influenced the luminescence properties of ZnO:Mo structures. The contact with hydrogen lead to an approximately threefold increase in intensity of the ultraviolet exciton-related band peaking at ~3.24 eV, whereas the red band attributed to zinc vacancies (~1.97 eV) was suppressed compared to the as-grown samples. The exciton- and defect-related emission subsided after the treatment in oxygen plasma.
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Xue D, Saito M, Osaka I, Marumoto K. Analyses of Charge Accumulation of PTzBT Ternary Polymer Solar Cells Using ESR Spectroscopy. J PHOTOPOLYM SCI TEC 2021. [DOI: 10.2494/photopolymer.34.351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dong Xue
- Division of Materials Science, University of Tsukuba
| | - Masahiko Saito
- Graduate School of Advanced Science and Engineering, Hiroshima University
| | - Itaru Osaka
- Graduate School of Advanced Science and Engineering, Hiroshima University
| | - Kazuhiro Marumoto
- Tsukuba Research Center for Energy Materials Science (TREMS), University of Tsukuba
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10
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Channel Defect Profiling and Passivation for ZnO Thin-Film Transistors. NANOMATERIALS 2020; 10:nano10061186. [PMID: 32570877 PMCID: PMC7353260 DOI: 10.3390/nano10061186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/11/2020] [Accepted: 06/17/2020] [Indexed: 11/23/2022]
Abstract
The electrical characteristics of Zinc oxide (ZnO) thin-film transistors are analyzed to apprehend the effects of oxygen vacancies after vacuum treatment. The energy level of the oxygen vacancies was found to be located near the conduction band of ZnO, which contributed to the increase in drain current (ID) via trap-assisted tunneling when the gate voltage (VG) is lower than the specific voltage associated with the trap level. The oxygen vacancies were successfully passivated after the annealing of ZnO in oxygen ambient. We determined that the trap-induced Schottky barrier lowering reduced a drain barrier when the drain was subjected to negative bias stress. Consequentially, the field effect mobility increased from 8.5 m2 V−1·s−1 to 8.9 m2 V−1·s−1 and on-current increased by ~13%.
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Wang H, Rong H, Wang D, Li X, Zhang E, Wan X, Bai B, Xu M, Liu J, Liu J, Chen W, Zhang J. Highly Selective Photoreduction of CO 2 with Suppressing H 2 Evolution by Plasmonic Au/CdSe-Cu 2 O Hierarchical Nanostructures under Visible Light. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2000426. [PMID: 32270917 DOI: 10.1002/smll.202000426] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/14/2020] [Accepted: 03/17/2020] [Indexed: 05/21/2023]
Abstract
Here, the photocatalytic CO2 reduction reaction (CO2 RR) with the selectivity of carbon products up to 100% is realized by completely suppressing the H2 evolution reaction under visible light (λ > 420 nm) irradiation. To target this, plasmonic Au/CdSe dumbbell nanorods enhance light harvesting and produce a plasmon-enhanced charge-rich environment; peripheral Cu2 O provides rich active sites for CO2 reduction and suppresses the hydrogen generation to improve the selectivity of carbon products. The middle CdSe serves as a bridge to transfer the photocharges. Based on synthesizing these Au/CdSe-Cu2 O hierarchical nanostructures (HNSs), efficient photoinduced electron/hole (e- /h+ ) separation and 100% of CO selectivity can be realized. Also, the 2e- /2H+ products of CO can be further enhanced and hydrogenated to effectively complete 8e- /8H+ reduction of CO2 to methane (CH4 ), where a sufficient CO concentration and the proton provided by H2 O reduction are indispensable. Under the optimum condition, the Au/CdSe-Cu2 O HNSs display high photocatalytic activity and stability, where the stable gas generation rates are 254 and 123 µmol g-1 h-1 for CO and CH4 over a 60 h period.
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Affiliation(s)
- Hongzhi Wang
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Hongpan Rong
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Dong Wang
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Xinyuan Li
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Erhuan Zhang
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Xiaodong Wan
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Bing Bai
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Meng Xu
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Jiajia Liu
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Jia Liu
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Wenxing Chen
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
| | - Jiatao Zhang
- Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, Experimental Center of Advanced Materials, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081, China
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Sarkar A, Chakrabarti M, Sanyal D, Gogurla N, Kumar P, Brusa RS, Hugenschmidt C. Depth resolved defect characterization of energetic ion irradiated ZnO by positron annihilation techniques and photoluminescence. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:085703. [PMID: 31469094 DOI: 10.1088/1361-648x/ab3f74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Depth resolved positron annihilation spectroscopy (PAS) has been employed to characterize the 1.2 MeV Ar and 800 keV O ion beam induced defects in ZnO. The first extraordinary result was the observation of defects in ion beam irradiated ZnO beyond the maximum penetration depth of the respective ions. The positron annihilation results revealed the formation of vacancy clusters consisting of both VZn and VO in ZnO which are saturated at a threshold radiation dose (defined as nuclear energy loss, Sn × fluence). From the photoluminescence (PL) spectra it has been observed that the PL intensity at the band edge degraded with the increase of open volume defects in ZnO. The evolution of the 2.4 eV PL, which is linked with the oxygen vacancies, is more significant due to Ar irradiation than the oxygen irradiation.
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Affiliation(s)
- A Sarkar
- Department of Physics, Bangabasi Morning College, 19 Rajkumar Chakraborty Sarani, Kolkata 700 009, India
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