First-principles calculations to investigate “H” and “K” doped RbSrF₃ for photovoltaic applications

A cubic perovskite RbSrF₃ structure has been doped with hydrogen and potassium, and their comparative study was carried out for the structural, electronic, and optical parameters. Self-consistent computation of ultra-soft pseudopotential plane-wave along with generalized gradient approximation (GGA) with Perdew Burke Ehrenzorf (GGA-PBE) exchange-correlation potential under the first principle is used for the computation of properties. Evaluated optimized lattice constant for Pm3m supercell is in good agreement with the already reported results and the bandgap reduces to a desired value for the “K” and “H” doping concentrations from 0% to 0.55%, this reduction is useful for water splitting and photovoltaic applications. The localized electrons for different bands are explained by DOS and PDOS. The optical properties for pure and H, K doped RbSrF₃ have been recognized by allocating the maximas obtained after calculations. This was the first-ever comparative theoretical study of this type for RbSrF₃ compound with the potassium and hydrogen dopants as far as our knowledge.