Why wo3 vaccum annealed sesnors shows higher resitance at vaccum?5 answersWO3 vacuum annealed sensors show higher resistance in vacuum due to the formation of a thin oxide layer on the surface of the sensor. This oxide layer acts as a barrier, preventing the flow of charge carriers and increasing the resistance of the sensor. The vacuum annealing process helps in the formation of this oxide layer, which is responsible for the higher resistance observed in vacuum conditions.
WO3 Nanoplates Film: Formation and Photocatalytic Oxidation Studies?3 answersWO3 nanoplates films were prepared using different methods and their photocatalytic oxidation properties were studied. Lai et al. found that controlling the fluoride content in the electrolyte during electrochemical anodization resulted in high surface area WO3 nanoplates films with efficient photocatalytic oxidation reaction. Wang et al. used a reactive magnetron method to prepare nanocrystalline/nanoporous WO3 thin films on glass plates and found that increasing the crystalline content and decreasing oxygen vacancies improved the photocatalytic degradation efficiency. McDonald et al. synthesized nanocrystalline WO3 nanoplatelets using microwave irradiation and found that they exhibited high photocatalytic oxidation activity for alcohol substrates. Thind et al. prepared bifunctional electrodes with WO3 nanoplatelets and Pt nanoparticles, which showed enhanced photocatalytic and electrocatalytic activities. Dirany et al. synthesized two-dimensional nanoplatelets of WO3 and found that they had a significant efficiency for photocatalytic decomposition of rhodamine B.
What is the effect of nitrogen doping on the properties of zinc oxide nanoparticles synthesized by the sol-gel method?5 answersNitrogen doping was not mentioned in any of the provided abstracts.
Band gap of anodization wo3 by fluoride??5 answersThe band gap of anodized tungsten trioxide (WO3) can be influenced by the presence of fluoride ions. In the study by Lee et al., WO3-decorated TiO2 nanotube arrays were synthesized using an in situ anodization method with dissolved ammonium fluoride. The incorporation of WO3 onto TiO2 nanotubes improved the mercury removal performance due to improved charge separation and decreased charge carrier recombination. Additionally, the band gap of WO3 can be reduced by doping it with NH4 through NH4OH treatment. The incorporation of NH4 into WO3 leads to a reduction in the band gap, lowering the onset potential and increasing the current density for the oxygen evolution reaction under illumination. Therefore, the presence of fluoride ions and NH4 doping can affect the band gap of anodized WO3.
Does anodization fluoride NH4F affect the band gap of WO3?5 answersAnodization with NH4F affects the band gap of WO3. Doping WO3 with NH4OH lowers the bandgap from 2.9 eV to 2.2 eV, regardless of the amount of NH4OH treatment. Doping WO3 with WO4- ions in an NH4F electrolyte also results in a red shift in the absorption edge of WO3-doped TiO2 nanotubes. Anodization in an NH4F/Na2SO4 electrolyte solution leads to the formation of visible light-responsive WO3 nanostructures with a lower band gap. Increasing the amount of NH4F in the electrolyte solution during anodization leads to the formation of thicker nanoporous WO3 layers. In situ doping of WO3 during anodic oxidation with NH4F also affects the resulting oxide morphology and phase composition.
What is the difference between WO3 grain size and its crystallite size?2 answersThe grain size of WO3 refers to the size of the particles or clusters of particles that make up the material, while the crystallite size refers to the size of the individual crystalline regions within those particles. In other words, the grain size is the size of the overall structure, while the crystallite size is the size of the individual building blocks of that structure. The grain size of WO3 can be controlled by factors such as concentration and amount of calcium chloride, concentration of tungstate solution, and type of mixing and stirring. On the other hand, the crystallite size of WO3 can be influenced by factors such as crystallite size radius and lattice strain induced by high energy ball milling. Understanding the difference between grain size and crystallite size is important for studying the properties and behavior of WO3 in various applications.