Effects of Annealing Process on the WO₃ Thin Films Prepared by Pulsed Laser Deposition

Abstract

This work presents a study of the effect of annealing temperature on the optical and structural properties of WO3 that has been deposited by Pulsed Laser Deposition (PLD) method at 300°C on the rules of glass and indicates the effect of annealing temperatures 350, 450 and 550°C for one hour on those properties. The results of X-Ray diffraction showed all the films prepared with the installation of multi-crystalline tetragonal and directional prevalent (010) for all models after annealing. The annealing led to an increase in the grain size. Full width at half maximum FWHM values of the (010) peaks of these films decreased from 1.492° to 1.064° with increasing annealing temperature, and the highest value of the specific surface area was 63 m2/gm. The natural structure of the WO3 nanoparticles films were studied by using field emission scanning electron microscopy (FESEM), it revealed that the average grain size increased with increasing of annealing temperature from 46.57 to 485.1nm. The optical features of the films were studied by Photoluminescence PL, the results gave one emission peaks located at 437 nm, and there was a red shift when the annealing temperatures were increased.

Anodizing Tungsten Foil with Ionic Liquids for Enhanced Photoelectrochemical Applications

“…43-1035). This result agrees with previous studies, as other researchers have reported that after annealing, amorphous WO 3 turned into a crystalline monoclinic phase [ 45 , 46 , 47 ]. Therefore, it is clear that the addition of ionic liquid in the electrolyte does not affect the crystalline properties of the synthesized nanostructures.…”

Correlation between Thickness and Optical Properties in Nanocrystalline γ-Monoclinic WO3 Thin Films

“…It is clear that after the annealing process at elevated temperatures the crystalline structure is affected in some way, and in this case, the preferential orientation takes part by temperature changes, the process crystallinity influences differently by having different thicknesses. As indicated by Yousif and Khudadad [68], it could be attributed to the atoms moving along the substrate surface to touch the weak energy nucleation sites and growing preferentially in that direction. The presence of oxygen vacancies accompanied by the presence of W mixed valence states, monitored in the structural changes of this work, and by varying the thickness, represents a major strategy for the development of highly efficient WO 3 -based materials, for control of the distribution or concentration of vacancies without involving complex methods [69].…”

Influence of the distance between nozzle and substrate on the structural, photoluminescence, and detector characteristics of p-NiO/n-Si hetero-junction deposited by spray pyrolysis method

“…The crystal size, the dislocation density, and the micro strain were calculated and tabulated in Table 1. They were calculated by the following formulas [39][40][41]:…”