DFT and experimental investigations on Pr substituted WO3 for electronic, thermoelectric and optical applications

Abstract

The properties of Pr-doped WO3 thin films were studied to examine the optical, thermoelectric, and electrical response for optoelectronic and photovoltaic applications. The thin films were synthesized using the spin coating technique. The various properties were explored by employing the DFT approach. The X-ray diffraction analysis showed the cubic phase crystalline structure of pure and Pr-doped compositions. The morphology contained uniform rod-like uniform features of WO3 thin films which changed to the un-even and non-uniform geometry with increased width in maximum Pr-doped compositions. The projected density of states revealed the major contribution of O-p in valance and W-d in the conduction band while Pr-f orbital showed an additional significant contribution in the Pr-doped compositions. The thermoelectric properties were significantly changed with the increase in Pr doping contents. The highest values of real epsilon and refractive index were found approximately 8.8 and 3.5 for maximum Pr-doped contents. The absorption coefficient and optical conductivity displayed an increasing trend with increment of Pr-doping contents suggesting the suitability with enhanced photovoltaic and optoelectronic properties. A reduction in the band gap of WO3 was observed with Pr-doping content.