Exploration energy harvesting through impurity-induced phenomena in barium titanate: First principle calculations

Abstract

In this study, we used the plane-wave pseudopotential technique with PBE-GGA implemented in CASTEP code to investigate the structural, electronic, elastic, mechanical, optical, and thermal properties of Ca, Sr, and Ca/Sr(co-doping) doped barium titanate perovskite. Structural transformation from cubic to tetragonal was observed. Formation energy confirms thermodynamic stability. The tolerance factor verifies the adoption of perovskite crystal structure. Pristine and all doped compositions have suitable bandgap for solar cell applications. After doping in BaTiO3, more density of states are available; hence, charge mobility increases. Doping in BaTiO3 also induced an effect on its optical, elastic, mechanical and thermal properties. The refractive index, extinction coefficient, and energy loss function are reduced, which enhances the absorptive nature of the material. Thermal characteristics all show the suitability for energy harvesting applications. All doped compositions fulfil the mechanical stability criteria. Poisson and Pugh's ratio suggest that doping transforms material nature from brittle to ductile, which make it a suitable candidate for flexible solar cell and optoelectronic devices.