Effect of carrier transport in NiO on the photovoltaic properties of lead iodide perovskite solar cells

Abstract

The effect of the NiOx thickness on the photovoltaic properties in planar type lead iodide perovskite solar cells consisted of Tin-doped indium oxide (ITO)/NiOx/Perovskite/Phenyl-C61-Butyric-Acid-Methyl Ester (PCBM)/Ag was investigated. For films ranging from 35nm to 120nm in the thickness, the NiOx thickness was found to be not crucial in fill factor and open circuit voltage. Calculations of the carrier flux in NiOx, estimated from Einstein-Smoluchowski relation and Fick's first law, found the carrier transport ability of the NiOx to fully compensate the photo-generated current density in perovskite layers and the theoretical current density ca. 26mAcm-2. The favorable physical properties such as mobility and thickness were also estimated for effective carrier transport in perovskite solar cells assuming that the carrier density is 1015cm-3.