Versatile Molybdenum Isopropoxide for Efficient Mesoporous Perovskite Solar Cells: Simultaneously Optimized Morphology and Interfacial Engineering

• Published in: Journal of physical chemistry. C 2016-07, Vol.120 (28), p.15089-15095
• Main Authors: Fu, Qingxia, Tang, Xianglan, Tan, Licheng, Zhang, Yong, Liu, Yawen, Chen, Lie, Chen, Yiwang
• Format: Article
• Language: English
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.6b04625

The high-quality CH3NH3PbI3 film morphology and delicate interfacial modification are critical to achieve high-performance perovskite solar cells (PSCs). Here, we report a facile and efficient method to optimize the morphology and interface of a perovskite solar cell by molybdenum isopropoxide (Mo-IPA) solution treatment during the fabrication process of the perovskite film. After simply being treated with Mo-IPA, both highly crystalline perovskite film and MoO X interfacial layer could be simultaneously achieved. The Mo-IPA treatment can induce a denser and more uniform morphology of CH3NH3PbI3 with larger crystals size than pure isopropyl alcohol (IPA) treatment. At the same time, the formation of MoO X can effectively elevate the valence band maximum (VBM) of the perovskite, as a result to favor a better energy alignment with 2,2′,7,7′-tetrakis­(N,N-di-p-methoxyphenylamine)­9,9′-spirobifluorene (Spiro-MeOTAD) hole transport layer (HTL) for efficient hole extraction. With those excellent properties obtained, the photovoltaic performance of the PSCs was remarkably increased from 10.8% to 12.0%.