Redox-inactive samarium(III) acetylacetonate as dopant enabling cation substitution and interfacial passivation for efficient and stable CsPbI2Br perovskite solar cells
Yang Yang,
Dong-Wei Han,
Ying Yang,
Si-Wei Yi,
Quan Yuan,
Dong-Ying Zhou,
Lai Feng
Affiliations
Yang Yang
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
Dong-Wei Han
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
Ying Yang
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
Si-Wei Yi
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
Quan Yuan
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
Dong-Ying Zhou
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
Lai Feng
College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou 215006, China
All-inorganic (CsPbX3) perovskites by replacing the volatile organic components with cesium cations allow extending the long-term thermal stability of perovskite solar cells (PeSCs) vs their organic–inorganic hybrid counterparts. However, the stability of α-CsPbI3 and α-CsPbI2Br still remains to be improved. In this work, we incorporate redox-inactive samarium acetylacetonate [Sm(acac)3] into CsPbI2Br to fabricate CsPbI2Br perovskite thin films. It is evidenced that Sm3+ not only partially substitute the Pb2+ sites to yield slightly contracted perovskite lattice but also modulate the perovskite growth and passivate the NiOx/CsPbI2Br interface. As a result, CsPbI2Br PeSCs based on stoichiometric and optimal Sm(acac)3 doping (0.15 mol. %) of CsPbI2Br show excellent photovoltaic metrics with a champion power conversion efficiency (PCE) of 12.86%. Moreover, the CsPbI2Br PeSCs exhibit enhanced thermal stability upon incorporation of Sm(acac)3, which retains 90% of their original PCE under heating at 85 °C for 200 h.
