Potential of AMnO3 (A=Ca, Sr, Ba, La) as Active Layer in Inorganic Perovskite Solar Cells

Abstract

Inorganic perovskite CaMnO ${}_3$ was proposed as a substitution for the TiO ${}_2$ anatase in electron transport layers of solar cells containing the hybrid perovskite CH ${}_3$ NH ${}_3$ PbI ${}_3$ based on increased mobility of electrons and better optical matching. Due to a suitable band gap concerning the absorption of sunlight, we investigate the potential of CaMnO ${}_3$ and similar manganite perovskites, where Ca is replaced by either Sr, Ba or La, as an absorber layer in inorganic perovskite solar cells. In this study, we have used optical measurements on the synthesized AMnO ${}_3$ (A=Ca, Sr, Ba, La) samples to aid density functional theory calculations (DFT) in order to accurately simulate the electronic and optical properties of AMnO ${}_3$ compounds and gauge their potential for the role of absorber layer. Both experimental measurements and theoretical calculations show suitable band gap of 1.1-1.5 eV, depending on the compound, and absorption coefficients of the order of ${10}^5$ cm ${}^{-1}$ in the visible part of the spectrum.

Keywords: absorber; active layer; density functional calculations; perovskites; solar cells.