First-principles study of ZnSn1-xTa_xO₃ (x=2.5% and x=5%) for opto-electronics and electronic structure properties

This study employs density functional theory (DFT) calculations to investigate the impact of tantalum (Ta) doping in ZnSnO3 to investigate the electronic and optoelectronic properties. ZnSnO3 is a promising semiconductor material with a wide bandgap and visible light transparency, making it suitable for optoelectronic applications. However, its low electrical conductivity limits its performance in these applications. The results revealed that our structural parameters are in good agreement with the experimental values. The electronic structures revealed that the top of the valence band and the bottom of the conduction band are decided by O 2p and Sn 5s states, respectively, and that ZnSn(1-x)TaxO(3) presented a direct band gap (1.0eV) located at Gamma-point. Finally, the complex dielectric function and optical constants (such as absorption spectrum, refractive index, extinction coefficient, reflectivity, and energy-loss spectrum) were obtained and discussed in detail. Our findings also suggested that ZnSn(1-x)TaxO(3) is a promising transparent semiconductor and photocatalyst. These insights provide opportunities for high-performance optoelectronic device design such as biomedical and LED.