Cesium Lead Inorganic Solar Cell with Efficiency beyond 18% via Reduced Charge Recombination. Issue 49 (21st October 2019)

• Record Type: Journal Article
• Authors: Ye, Qiufeng; Zhao, Yang; Mu, Shaiqiang; Ma, Fei; Gao, Feng; Chu, Zema; Yin, Zhigang; Gao, Pingqi; Zhang, Xingwang; You, Jingbi
• Is Part Of: Advanced materials. Volume 31:Issue 49(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-10-21
• Subjects: inorganic perovskite solar cells -- recombination defects -- VOC loss; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201905143
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Cesium‐based inorganic perovskite solar cells (PSCs) are promising due to their potential for improving device stability. However, the power conversion efficiency of the inorganic PSCs is still low compared with the hybrid PSCs due to the large open‐circuit voltage ( V OC ) loss possibly caused by charge recombination. The use of an insulated shunt‐blocking layer lithium fluoride on electron transport layer SnO2 for better energy level alignment with the conduction band minimum of the CsPbI3‐ x Br x and also for interface defect passivation is reported. In addition, by incorporating lead chloride in CsPbI3‐ x Br x precursor, the perovskite film crystallinity is significantly enhanced and the charge recombination in perovksite is suppressed. As a result, optimized CsPbI3‐ x Br x PSCs with a band gap of 1.77 eV exhibit excellent performance with the best V OC as high as 1.25 V and an efficiency of 18.64%. Meanwhile, a high photostability with a less than 6% efficiency drop is achieved for CsPbI3‐ x Br x PSCs under continuous 1 sun equivalent illumination over 1000 h. Abstract : The power conversion efficiency of inorganic perovskite solar cells (PSCs) is still low compared with hybrid PSCs. The use of lithium fluoride on SnO2 and PbCl2 additive in perovskite is reported for reducing the charge recombination; 18.64% efficiency of CsPbI3– x Br x solar cells is demonstrated; and the devices show over than 1000 h light soaking stability.