Intermediate phase assisted sequential deposition of reverse‐graded quasi‐2D alternating cation perovskites for MA‐free perovskite solar cells
Shaofu Wang,
Yumin Liu,
Junjie Zou,
Junjun Jin,
Yun Jiang,
Tao Zeng,
Wenyan Zhao,
Rong‐Xiang He,
Bolei Chen,
Yu Chen,
Shuoxue Jin,
Hong‐Xiang Li,
Zhipeng Xie,
Chang‐An Wang,
Weiwei Sun,
Qiang Cao,
Xing‐Zhong Zhao
Affiliations
Shaofu Wang
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Yumin Liu
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Junjie Zou
School of Physics and Technology, Institute of Technological Sciences, Key Laboratory of Artificial Micro/Nano Structures, Ministry of Education Wuhan University Wuhan the People Republic of China
Junjun Jin
School of Physics and Technology, Institute of Technological Sciences, Key Laboratory of Artificial Micro/Nano Structures, Ministry of Education Wuhan University Wuhan the People Republic of China
Yun Jiang
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Tao Zeng
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Wenyan Zhao
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Rong‐Xiang He
Institute for Interdisciplinary Research (IIR), Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education Jianghan University Wuhan the People Republic of China
Bolei Chen
Institute for Interdisciplinary Research (IIR), Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education Jianghan University Wuhan the People Republic of China
Yu Chen
Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences Beijing the People Republic of China
Shuoxue Jin
Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences Beijing the People Republic of China
Hong‐Xiang Li
College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering Sichuan University Chengdu the People Republic of China
Zhipeng Xie
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Chang‐An Wang
School of Materials Science and Engineering, National Engineering Research Center for Domestic & Building Ceramics Jingdezhen Ceramic University Jingdezhen the People Republic of China
Weiwei Sun
College of Aerospace Science and Engineering National University of Defense Technology Changsha the People Republic of China
Qiang Cao
School of Physics and Technology, Institute of Technological Sciences, Key Laboratory of Artificial Micro/Nano Structures, Ministry of Education Wuhan University Wuhan the People Republic of China
Xing‐Zhong Zhao
School of Physics and Technology, Institute of Technological Sciences, Key Laboratory of Artificial Micro/Nano Structures, Ministry of Education Wuhan University Wuhan the People Republic of China
Abstract One‐step deposition approaches have been widely applied and developed in the fabrication of quasi‐2D perovskites. However, the regulation of quantum wells (QWs) and crystalline orientation is difficult and complicated when using this methodology. Sequential deposition is another widespread synthetic approach for preparing perovskite films and perovskite dimension engineering. In this article, δ‐CsPbI3 intermediate phase assisted sequential (IPAS) deposition is successfully carried out to fabricate MA‐free quasi‐2D ACI perovskites. The amount of the δ‐CsPbI3 intermediate phase in the PbI2 layer and the concentration of GAI molecule in the IPA solution both play important roles in the production of MA‐free quasi‐2D ACI perovskite films. The n value of the MA‐free quasi‐2D ACI perovskites can be adjusted, which affects the photovoltaic performance and device stability. Compared with one‐step deposition, the MA‐free quasi‐2D ACI perovskites prepared via IPAS deposition have opposite reverse‐graded QW distribution and improved vertical orientation, leading to a remarkable PEC of up to 18.86% and allowing the preparation of unpackaged devices with prominent working stability (80%, ~400 h). The underlying mechanism and crystallization pathway of IPAS deposition confirm that sequential deposition has unique superiority in regulating the QW distribution and crystalline orientation of quasi‐2D perovskites.