Theoretical and experimental study of the optoelectronic, thermodynamic and vibrational properties of the nanostructure of m-WO3

Abstract

Tungsten trioxide (WO3), an n-type semiconductor, has attracted attention due to its diversity of properties, such as catalytic activity, gas sensing capabilities, photochromic behavior, and its ability to absorb both ultraviolet and visible light. This study aimed to investigate the monoclinic phase of the synthesized WO3 (m-WO3) through a combination of computational and experimental studies. We present the results of a theoretical investigation on m-WO3 using first-principles calculations (ab initio) and the pseudopotential model of plane waves. The Density Functional Theory (DFT) was employed, utilizing both the Local Density Approximation (LDA) and Generalized Gradient Approximation (GGA) to account for exchange potential and correlation effects. Structural properties, electron band structure, electron density of states, and optical properties (reflectivity and optical absorption) were computed for the optimized nanostructure at its lowest energy state. A comparison between the calculated lattice parameters and theoretical/experimental results revealed a good agreement. Furthermore, the thermodynamic potentials and specific heat at the constant volume of the nanostructure were calculated. Infrared (IR) and Raman spectra within the frequency range of 0–1000 cm−1 were estimated and assigned, and the results were compared with experimental data and demonstrated good agreement with the literature.