Exploring thermoelectric and optical response of Zn_xW_1-xO₃ using comparative simulation and experimental techniques

Abstract Zn x W 1-x O 3 have been examined through simulation and experimental methods to investigate its suitability for wide-range optical and thermoelectric applications. The simulations were performed prior to the experimental investigations using density functional calculations based TB-mBJ approximation. Same compositions were grown in uniform phase pure crystalline form. X-ray diffraction analysis revealed the cubic phase structures in synthesized compositions. The pure films comprised an aggregated irregular granular geometry which prominently changed upon Zn incorporation and converted into a distinctive smaller-sized granular structures. Zn containing compositions show a prominent contribution of O- p , W- d , and Zn- d orbitals by the projected density of states analysis. A significant alteration was observed in the thermoelectric parameters after the integration of Zn content into host material. The highest extinction coefficient and refractive index values were observed as 1.5 and 1.78, respectively, for maximum Zn containing composition. The enhanced optical conductivity in doped composition illustrated a significant modulation in tungsten trioxide optical characteristics. Further, the experimentally observed band gap (2.44 eV) of pure WO 3 was strategically reduced with the increment of Zn content suggesting these compositions favorable potential photovoltaics and optoelectronics.