A halide exchange engineering for CH3NH3PbI3−xBrx perovskite solar cells with high performance and stability. (January 2016)

• Record Type: Journal Article
• Authors: Zhu, Weidong; Bao, Chunxiong; Li, Faming; Yu, Tao; Gao, Hao; Yi, Yong; Yang, Jie; Fu, Gao; Zhou, Xiaoxin; Zou, Zhigang
• Is Part Of: Nano energy. Volume 19(2016:Jan.)
• Page Start: 17
• Page End: 26
• Publication Date: 2016-01
• Subjects: CH3NH3PbI3 -- Halide exchange -- Post-treatment -- Perovskite solar cell -- Stability; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2015.11.024
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: A facile halide exchange route based on CH3 NH3 Br solution post-treatment has been successfully employed to transform the two-step spin-coated CH3 NH3 PbI3 films into the CH3 NH3 PbI3− x Br x films, whose morphologies and compositions could be modified simultaneously. With the increase of CH3 NH3 Br solution concentration, the CH3 NH3 PbI3− x Br x films exhibited increased grain size, prolonged charge carrier lifetime, and enlarged bandgap with slightly reduced light absorption compared with the parent CH3 NH3 PbI3 film. The mesostructured perovskite solar cells based on the CH3 NH3 PbI3− x Br x films yielded the optimal power conversion efficiency (PCE) of 14.25%, which is much higher than that of device with the parent CH3 NH3 PbI3 film. In particular, the device based on the CH3 NH3 PbI3− x Br x film retained up to 93% of its original PCE after exposed to air for 14 days without any encapsulation, presenting a favorable stability. Our work suggests a novel and attractive way to fabricate high-performance perovskite solar cells with excellent stability. Graphical abstract: The perovskite solar cells based on CH3 NH3 PbI3− x Br x film via a facile halide exchange route showed significantly enhanced efficiency and stability in atmosphere. Highlights: The halide exchange route was used to transform CH3 NH3 PbI3 films into CH3 NH3 PbI3− x Br x films. The morphologies and compositions of the CH3 NH3 PbI3− x Br x films could be controllably modified. The optimal cell with CH3 NH3 PbI3− x Br x film showed substantially improved efficiency of 14.25% and stability in air.