Mechanism of Creation and Destruction of Oxygen Interstitial Atoms by Nonpolar Zinc Oxide(10\bar{1}0) Surfaces

2021 ◽  
Author(s):  
Heonjae Jeong ◽  
Ming Li ◽  
Jingtian Kuang ◽  
Elif Ertekin ◽  
Edmund G Seebauer
Keyword(s):  
Zinc Oxide ◽  
Oxygen Vacancies ◽  
Semiconductor Devices ◽  
Synthesis Methods ◽  
Oxygen Interstitial ◽  
Interstitial Atoms ◽  
Post Synthesis

Oxygen vacancies (VO) influence many properties of ZnO in semiconductor devices, yet synthesis methods leave behind variable and unpredictable VO concentrations. Oxygen interstitials (Oi) move far more rapidly, so post-synthesis...

Fabrication of indium gallium zinc oxide phototransistors via oxide-mesh insertion for visible light detection

2020 ◽  
Vol 8 (1) ◽  
pp. 165-172 ◽  
Author(s):  
Dongwoo Kim ◽  
Yeong-gyu Kim ◽  
Byung Ha Kang ◽  
Jin Hyeok Lee ◽  
Jusung Chung ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Visible Light ◽  
Oxygen Vacancies ◽  
Indium Gallium Zinc Oxide ◽  
Light Detection ◽  
Indium Gallium

Visible light detection of oxide phototransistors via insertion of an oxide-mesh inside the channel creating oxygen vacancies that increase subgap states.

The Impact of Hydrogen Plasma Treatments at Moderate Temperatures on Sintered Zinc Oxide Samples - Evidence for Hydrogen Induced Nano-Void Formation

2006 ◽  
Vol 957 ◽  
Author(s):  
Reinhart Job
Keyword(s):  
Zinc Oxide ◽  
Oxygen Vacancies ◽  
Hydrogen Plasma ◽  
Void Formation ◽  
Vibration Modes ◽  
Plasma Exposure ◽  
Plasma Treatments ◽  
The Impact ◽  
Substrate Temperatures ◽  
Defect Species

ABSTRACTUsing μ-Raman spectroscopy (μRS) analyses, the impact of hydrogen plasma treatments on sintered zinc oxide (ZnO) samples was investigated. H-plasma exposures (150 W, 13.56 MHz) were carried out for 1 hour at substrate temperatures between 250 °C and 500 °C. μRS reveals that plasma hydrogenated ZnO samples are more defective than non-treated ones. On one hand non-specified defect species are created with a maximal density upon plasma hydrogenation at 350 °C, on the other hand the formation of oxygen vacancies (VO) can be traced. The density of VO defects, appearing upon H-plasma exposure, is not significantly correlated to the applied substrate temperatures. μRS also reveals vibration modes of H2 molecules trapped in nano-voids. The μRS results indicate that those nano-voids are created by the coalescence of VO defects.

Synthesis and Antimicrobial Properties of Zinc Oxide Nanoparticles

2020 ◽  
Vol 20 (10) ◽  
pp. 5977-5996 ◽  
Author(s):  
Saee Gharpure ◽  
Balaprasad Ankamwar
Keyword(s):  
Zinc Oxide ◽  
Zno Nanoparticles ◽  
Zinc Oxide Nanoparticles ◽  
Metal Oxide Nanoparticles ◽  
Antibacterial Properties ◽  
Antimicrobial Properties ◽  
Physical Contact ◽  
Oxide Nanoparticles ◽  
Synthesis Methods ◽  
Promising Alternative

With increase in incidence of multidrug resistant pathogens, there is a demand to adapt newer approaches in order to combat these diseases as traditional therapy is insufficient for their treatment. Use of nanotechnology provides a promising alternative as antimicrobial agents as against traditional antibiotics. Metal oxides have been exploited for a long times for their antimicrobial properties. Zinc oxide nanoparticles (ZnO NPs) are preferred over other metal oxide nanoparticles because of their bio-compatible nature and excellent antibacterial potentials. The basic mechanism of bactericidal nature of ZnO nanoparticles includes physical contact between ZnO nanoparticles and the bacterial cell wall, generation of reactive oxygen species (ROS) as well as free radicals and release of Zn2+ ions. This review focuses on different synthesis methods of ZnO nanoparticles, various analytical techniques frequently used for testing antibacterial properties, mechanism explaining antibacterial nature of ZnO nanoparticles as well as different factors affecting the antibacterial properties.

scholarly journals Recent Advancements in the Understanding of the Surface Chemistry in TiO2 Photocatalysis

Surfaces ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 72-92 ◽  
Author(s):  
Alexander V. Vorontsov ◽  
Héctor Valdés ◽  
Panagiotis G. Smirniotis ◽  
Yaron Paz
Keyword(s):  
Surface Chemistry ◽  
Surface Science ◽  
Oxygen Vacancies ◽  
Anatase Phase ◽  
Review Article ◽  
Theoretical Research ◽  
Synthesis Methods ◽  
Theoretical Methods ◽  
Structure Of Nanoparticles ◽  
Nanoscale Level

Surface chemistry plays a major role in photocatalytic and photoelectrochemical processes taking place with the participation of TiO2. The synthesis methods, surface characterizations, theoretical research methods, and hardware over the last decade generated opportunities for progress in the surface science of this photocatalyst. Very recently, attention was paid to the design of photocatalysts at the nanoscale level by adjusting the types of exposed surfaces and their ratio, the composition and the surface structure of nanoparticles, and that of individual surfaces. The current theoretical methods provide highly detailed designs that can be embodied experimentally. The present review article describes the progress in the surface science of TiO2 and TiO2-based photocatalysts obtained over the last three years. Such aspects including the properties of macro- and nano-scale surfaces, noble-metal-loaded surfaces, doping with Mg and S, intrinsic defects (oxygen vacancies), adsorption, and photoreactions are considered. The main focus of the article is on the anatase phase of TiO2.

scholarly journals MOF derived graphitic carbon nitride/oxygen vacancies-rich zinc oxide nanocomposites with enhanced supercapacitive performance

Ionics ◽  
2020 ◽  
Vol 26 (10) ◽  
pp. 5155-5165 ◽  
Author(s):  
Jiaqi Shen ◽  
Peng Wang ◽  
Huasheng Jiang ◽  
Hui Wang ◽  
Bruno G. Pollet ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Carbon Nitride ◽  
Oxygen Vacancies ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Supercapacitive Performance

scholarly journals Microwave-assisted synthesis and characterization of microstar shaped zinc oxide

Quimica Hoy ◽  
2012 ◽  
Vol 2 (3) ◽  
pp. 3
Author(s):  
Idalia Gómez ◽  
Miguel José Yucam´án ◽  
Flor Palomar
Keyword(s):  
Electron Microscopy ◽  
Zinc Oxide ◽  
Microwave Assisted Synthesis ◽  
Stoichiometric Ratio ◽  
Crystalline Materials ◽  
Microwave Assisted ◽  
Transmission Electron ◽  
Synthesis Procedure ◽  
Post Synthesis

A microwave-assisted solution-phase approach has been applied for the synthesis ofzinc oxide microstructures. Toe synthesis procedure was carried out by using the reagents: Zinc ni trate and Methenamine, at stoichiometric ratio. Analysis by means ofX-ray Diffraction (XRD) shows a crystalline phase in hexagonal wurtzite arrangement for ZnO. The presence ofmicrostar shaped zinc oxide (2-3μm) with nanorods,f50nm) arranged has been confirmed from High Resolution Scanning Electron Microscopy (HRSEM). The formation of nanorods was confirmed by Transmission Electron Microscopy. In Raman spectroscopy a red shift was detected in the microstructures compared with ZnO bulk. High crystalline materials without additional post-synthesis treatrnent were found.

scholarly journals Zinc Oxide Nanoparticles Synthesis Methods and its Effect on Morphology: A Review

2021 ◽  
Vol 12 (3) ◽  
pp. 4261-4292
Keyword(s):  
Zinc Oxide ◽  
Nanocrystalline Materials ◽  
Sol Gel ◽  
Synthesis Process ◽  
Synthesis Methods ◽  
Efficient Synthesis ◽  
Synthesis Of Nanoparticles ◽  
Key Factor ◽  
Control Of Parameters ◽  
Biological Methods

Zinc oxide is an important material with numerous applications due to its unique properties. Due to their thermal and chemical stability are used in wide applications such as LEDs, sensors, catalysts, and photodetectors. Different chemical, physical, and biological methods have been adopted to achieve the intended result, as enumerated in many pieces of literature. Therefore, selecting an efficient synthesis process is essential, which is a key factor that significantly influences the efficacy of the synthesized nanocrystalline materials. The chemical synthesis of nanoparticles (NPs) via hydrothermal, solvothermal, and sol-gel routes is considered effective as high-quality crystalline structures are produced. Control of parameters of processes yields excellent morphological features of the synthesized samples. This review explored the different parameters of processes and their effect on the morphology of ZnO nanostructures via hydrothermal, solvothermal, and sol-gel techniques. Finally, some ZnO nanocomposites molecules are reviewed as per the dopant used and its effect on the sample compound synthesized.

scholarly journals Removal of Organic Dyes from Water and Wastewater Using Magnetic Ferrite-Based Titanium Oxide and Zinc Oxide Nanocomposites: A Review

Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1543
Author(s):  
António B. Mapossa ◽  
Washington Mhike ◽  
José L. Adalima ◽  
Shepherd Tichapondwa
Keyword(s):  
Zinc Oxide ◽  
Visible Light ◽  
Titanium Oxide ◽  
Organic Dyes ◽  
Organic Pollutant ◽  
Synthesis Method ◽  
Degradation Efficiency ◽  
Commercial Application ◽  
Synthesis Methods ◽  
Subsequent Formation

Heterogeneous photocatalysis using titanium dioxide (TiO2) and zinc oxide (ZnO) has been widely studied in various applications, including organic pollutant remediation in aqueous systems. The popularity of these materials is based on their high photocatalytic activity, strong photosensitivity, and relatively low cost. However, their commercial application has been limited by their wide bandgaps, inability to absorb visible light, fast electron/hole recombination, and limited recyclability since the nanomaterial is difficult to recover. Researchers have developed several strategies to overcome these limitations. Chief amongst these is the coupling of different semi-conductor materials to produce heterojunction nanocomposite materials, which are both visible-light-active and easily recoverable. This review focuses on the advances made in the development of magnetic ferrite-based titanium oxide and zinc oxide nanocomposites. The physical and magnetic properties of the most widely used ferrite compounds are discussed. The spinel structured material had superior catalytic and magnetic performance when coupled to TiO2 and ZnO. An assessment of the range of synthesis methods is also presented. A comprehensive review of the photocatalytic degradation of various priority organic pollutants using the ferrite-based nanocomposites revealed that degradation efficiency and magnetic recovery potential are dependent on factors such as the chemical composition of the heterojunction material, synthesis method, irradiation source, and structure of pollutant. It should be noted that very few studies have gone beyond the degradation efficiency studies. Very little information is available on the extent of mineralization and the subsequent formation of intermediate compounds when these composite catalysts are used. Additionally, potential degradation mechanisms have not been adequately reported.

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