Air-processed carbon-based perovskite solar cells with enhanced efficiency and stability: Effect of temperature control and using CuSCN

Recently, fully air-processed perovskite solar cells have attracted a large number of research workers to promote the process of large-scale productions of perovskite solar cell devices. In this paper, we use a simple substrate preheating at a controlled temperature ranging from 313 K to 353 K to prepare the full coverage and uniform mixed-ion FA 0.83 MA 0.17 PbI 2·49 Br 0.51 perovskite films via a one-step deposition method in ambient air with a relative humidity of 30%∼50%. A high-quality air-processed perovskite film is obtained at an optimized temperature of 333 K. The perovskite solar cells with and without using CuSCN obtain the champion power conversion efficiencies of 14.87% and 11.12% at an optimized substrate preheating temperature of 333 K. The device using CuSCN show 34% increase in power conversion efficiency, which is mainly attributed to the more efficient hole extraction between perovskite and CuSCN, thus contributing to the lower recombination of electrons and holes. The best performed cell without encapsulation displays high stability via 30 days stability tests. High-efficiency fully air-processed devices using CuSCN as hole transport layer and carbon as the back contact electrode are potential candidates for large-scale production of perovskite solar cell.