Electronic and optical properties of multifunctional R3c AFeO3 (A = Sc or In) compounds: Insights into their potential for photovoltaic applications

Employing the spin density functional theory calculations we have investigated the electronic and optical properties of multifunctional R3c AFeO(3) (A = Sc or In) compounds in order to understand their potential for photovoltaic applications. Due to a lack of experimental information about these properties, we used a welldocumented, isostructural BiFeO3 compound as a benchmark to be compared with. To approximate the exchange and correlation effects, we employed the local spin density approximation (LSDA) including effective Hubbard U correction (U-eff = 6.0 eV) for the Fe 3d band. Based on this methodology, we found that the ScFeO3 and InFeO3 exhibit direct energy band gaps of 3.0 eV and 2.6 eV, respectively, and absorb visible light in the extreme part of the visible solar spectrum. The calculated effective masses (m*) are found to be comparable to those of the commercial conventional semiconductors (m* <= 0.5 m(0)). Energies of dissociation of the excitons are estimated to be very low (<2.0 meV), well below the energy of thermal excitation (KBT similar to 26 meV). All of these properties are comparable to those of the BiFeO3, which is already utilized in photovoltaic applications. Thus, we conclude that the ScFeO3 and InFeO3 also have a great potential to be used for the same purpose.

Automated summary

Using spin density functional theory calculations, the electronic and optical properties of multifunctional R3c AFeO(3) compounds were investigated to understand their potential for photovoltaic applications. It was found that ScFeO3 and InFeO3 have direct energy band gaps and absorb visible light, comparable to the properties of BiFeO3 used in photovoltaic applications. Therefore, it is concluded that ScFeO3 and InFeO3 also have great potential for use in the field of photovoltaics.