Study of optoelectronic and thermoelectric properties of double perovskites for renewable energy

Abstract

Abstract It is compulsory to develop technologies able to generate energy at negligible cost to the environment. Therefore, in present work, lead free vacancy ordered double perovskites M 2 TeBr 6 (M = Rb, Cs) were reported as green energy materials on basis of full potential linearized augmented plane wave method calculations. The study has been carried out in terms of structural, mechanical, electronic, optical, and thermoelectric properties. It was noted from values of tolerance factor and formation energy that both the M 2 TeBr 6 compounds are stable in perovskite structure. The band gaps were calculated as indirect of values 2.09 eV for Rb 2 TeBr 6 and 2.10 eV for Cs 2 TeBr 6 with EV-GGA. These gaps were found in close resemblance with experimental results. The optical properties such as real and imaginary parts of dielectric function, optical conductivity and reflectivity calculated via EV-GGA ensured the use of both the M 2 TeBr 6 compounds for optoelectronic devices and solar cell applications. Also, the reasonable values of Seebeck coefficients and figure of merit suggested the studied compounds for thermoelectric power generation.