Metallic electrode interfacial properties
have a crucial impact
on the performance of photovoltaic devices. The interfacial interactions
between electrodes and transport layers are critical for charge separation,
transport, and collection. Herein, we investigate the interfacial
interaction between the aluminum electrode and 6,6-phenyl-C61-butyric
acid methyl ester (PCBM) on the performance in two-dimensional perovskite
photovoltaic devices. It is observed that the aluminum oxide dielectric
layer formed at the interface of aluminum electrode and PCBM, accumulating
charges to achieve a high voltage (>5 V) in two-dimensional perovskite
photovoltaic devices. Further regulating the aluminum oxide layer
can optimize the device performance (voltage, current density, series
resistance, and efficiency). The capacitive effect of the aluminum
oxide dielectric layer is responsible for this high voltage response.
This work will provide a reference for future research on the electrode/PCBM
interface in perovskite photovoltaic devices.