Investigation of the impact of transition metals (TM = Fe, Co, Ni) doping on the optoelectronic properties of tin dioxide SnO2: first-principles analysis

Abstract

In this paper, we applied the density functional theory method, within the framework of GGA+U methods, to study the optoelectronic properties of undoped tin dioxide SnO2. The effect of substitutional doping of transition metals (TM) in Sn-site on these properties was also investigated in Sn0.92TM0.08O2 with TM = Fe, Co, Ni. Initially, we studied the Hubbard parameters U and the starting spin polarization to determine their optimal values. From the band structures, Sn0.92TM0.08O2 appears to be a dilute magnetic semiconductor (DMS) with a direct bandgap. Our analysis of the total density of states revealed variations in the bandgap and Fermi level. Additionally, we explored the optical properties of these compounds in the UV, visible light, and infrared regions IR, observing a decrease in peak intensity and a shift from the IR to the UV-visible region. These findings align well with experimental studies and aim to provide interpretations and guidelines for future experimental work.