Perovskite solar cell based on double-layer Ag/SnBi alloy as cathode

Herein, a low-melting point tin-bismuth (SnBi) alloy film combined with a silver layer was introduced to fabricate the inverted planar perovskite solar cells. SnBi alloy was prepared by high temperature melting method and was characterized by metallurgical microscope, XRD, SEM, DTA, XPS methods. The influence of silver thickness on the performance of perovskite solar cells was studied. The optimized perovskite solar cells based on 20 nm Ag and 80 nm SnBi show a power conversion efficiency of 13.52%, involving a 19.6% increase compared to the control device. The double-layer electrode can not only reduce the charge transfer resistance, increase the extraction efficiency of the charge, improve the photovoltaic performance of the device, but also improve the stability of the device in the environment.