Structural, electronic, thermoelectric, and optical investigations on Cr substituted Ta2O5

Investigation on different materials at the nanoscale has transformed the significant aspects of technology, especially the revolution in microelectronic and optoelectronic devices. In this context, the first principle and experimental investigations on Cr-doped Ta2O5 compositions are presented. The simulations for electronic, thermoelectric and optical properties were performed through DFT TB-mBJ calculations. The p -d hybridization between Ta and O atoms appeared in the density of states spectra. Experimentally, Cr-doped Ta2O5 thin films were fabricated through a well-known magnetron sputtering technique. The crystallographic studies reveal the growth of the orthorhombic structure of Ta2O5. The Cr in thin films leads to grain growth which increases with Cr dopant content. Thermoelectric properties especially the Seebeck coefficient of Cr-containing compositions are improved. The optical parameters are recorded as a function of photon energy which shows a resemblance in simulation and experimental results. The maximum value of the experimental refractive index for all compositions was noticed at the highest energy regimes and found to increase from 2.34 to 3.65 with maximum Cr content. Similarly, the maximum value of real epsilon enhanced from 3.59 to 12.01. The improved thermoelectric and optical properties make these compositions favorable for energy harvesting and photovoltaic applications.