2022 Science: Beyond 24% Efficiency! How to Build an Interfacial Heterojunction for Inverse Perovskite Solar Cells?
This study adopted the idea of constructing an interface heterojunction to increase the built-in potential and enhances the built-in potential of reverse perovskite cells.
- Through surface sulfidation, an efficient interfacial heterojunction was constructed, and the reverse perovskite cell with an efficiency >24% was realized for the first time.
- The perovskite solar cell showed excellent stability, the MPP output is 1000h under continuous illumination, and the efficiency decay is less than 10%.
Reverse perovskite cells have the advantages of simple process, low temperature preparation, and compatibility with crystalline silicon cells, and have greater development potential. However, the current high-efficiency perovskite cells all adopt the forward structure, and the efficiency of reverse perovskite cells has been low.
In this paper, for the reverse perovskite solar cell, through the design of the interface heterojunction, the reverse perovskite solar cell with an efficiency > 24% was realized for the first time. Moreover, PbS and perovskite had similar lattice parameters, and the Pb-S bond was much stronger than the Pb-I bond, which could stabilize the perovskite structure and the interface, thereby improving the stability.
After surface sulfidation, the reverse perovskite cell efficiency was improved from the initial 21.8% to 24.3% with
almost no hysteresis.
The PbPyA2 and TMS concentrations required for the surface vulcanization process had an impact on the device efficiency, and the optimal conditions was PbPyA2 1mg/mL, TMS 3mg/mL.
Keywords:：constructing heterojunction, inverted perovskite solar cell, Solar Simulator, Sun Simulator