Improved photovoltaic performance from inorganic perovskite oxide thin films with mixed crystal phases

Inorganic ferroelectric perovskites are attracting attention for the realization of highly stable photovoltaic cells with large open-circuit voltages. However, the power conversion efficiencies of devices have been limited so far. Here, we report a power conversion efficiency of ~4.20% under 1 sun illumination from Bi–Mn–O composite thin films with mixed BiMnO3 and BiMn2O5 crystal phases. We show that the photocurrent density and photovoltage...