Yicheng Zhao1,2, Qi Li2, Wenke Zhou2, Yi Hou1, Yao Zhao2, Rui Fu2, Dapeng Yu3,2, Xin Liu4, Qing Zhao3,2
1Institute of Materials for Electronics and Energy Technology (i‐MEET), Department of Materials Science and Engineering Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Martensstr. 7 91058 Erlangen Germany
2State Key Laboratory for Mesoscopic Physics and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
3Collaborative Innovation Center of Quantum Matter, Beijing 100084, China
4Global Energy Interconnection Research Institute, Beijing, 100871 China
Tóm tắt
An ideal crystal quality in the grain interior of perovskite polycrystalline films is well recognized; therefore, understanding interfacial impact and the ways to limit interfacial recombination is critical to fabricating highly efficient solar cells. In perovskite solar cells, PbI2 has been used to passivate defects at grain boundaries, yet a systematic PbI2 passivation engineering to boost the high‐performance perovskite solar cells has not been fully explored. Here, a novel device structure comprised of double‐side‐passivated perovskite solar cells (DSPC) is devised through intentionally distributing PbI2 to both the front/rear‐side surfaces and grain boundaries of the formamidinium‐lead‐iodide‐based (FAPbI3‐based) perovskite film. The minority carrier lifetime in double‐side‐passivated perovskite is extended to 1.1 μs with single‐exponential decay using time‐resolved photoluminescence. This result indicates a generic passivation effect of PbI2 on perovskite interfaces, resembling SiO2 passivation in silicon solar cells. Correspondingly, the best photovoltaic device with TiO2‐based planar structure presents a stabilized efficiency of 22%. Moreover, DSPC effectively boosts the limits of open circuit voltages toward a record potential loss of 0.38 V for 1.53 eV‐bandgap perovskites. The architecture of double‐side‐passivated perovskite opens up new opportunities to exceed the efficiency of state‐of‐the‐art perovskite solar cells.
