Effect of substrate preheating on the photovoltaic performance of ZnO nanorod-based perovskite solar cells

Abstract

In this study, zinc oxide nanorods (ZnO-NRs) grown via a low-temperature hydrothermal growth process are used as the electron transport layer (ETL) owing to their low temperature process and three-dimensional structure, which increases the surface area and thereby improves photovoltaic performance. To further improve the performance of solar cells, substrate preheating before spin-coating PbI2 and perovskite films was conducted. With the increase in preheating temperature, the grain size, surface uniformity, and crystallinity of perovskite increased. Consequently, the photovoltaic performances of the devices with 150-nm-long ZnO-NRs and substrate preheating at 150 degrees C showed an optimum open-circuit voltage (V-oc) of 0.84V, a short-circuit current (J(sc)) of 21.43 mA/cm(2), a fill factor (FF) of 57.42%, and a power conversion efficiency (PCE) of 10.34% owing to the superior quality of the perovskite films having smooth surfaces with fewer pinholes. (c) 2018 The Japan Society of Applied Physics