A Key 2D Intermediate Phase for Stable High‐Efficiency CsPbI2Br Perovskite Solar Cells. Issue 2 (2nd December 2021)

• Record Type: Journal Article
• Authors: Yang, Shaomin; Wen, Jialun; Liu, Zhike; Che, Yuhang; Xu, Jie; Wang, Jungang; Xu, Dongfang; Yuan, Ningyi; Ding, Jianning; Duan, Yuwei; Liu, Shengzhong (Frank)
• Is Part Of: Advanced energy materials. Volume 12:Issue 2(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-02
• Subjects: perovskite solar cells -- CsPbI 2Br -- high efficiency -- imidazolium halide -- low‐dimensional intermediate‐assisted growth; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202103019
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Inorganic CsPbI2 Br perovskite is promising for solar cell applications due to its excellent thermal stability and optoelectronic characteristics. Unfortunately, the current high‐efficiency CsPbI2 Br perovskite solar cells (PSCs) are mostly fabricated in an inert atmosphere due to their instability to moisture. Herein, a low‐dimensional intermediate‐assisted growth (LDIAG) method is reported for the deposition of CsPbI2 Br film in ambient atmosphere by introducing imidazole halide (IMX: IMI and IMBr) into the precursor solution to control both nucleation and growth kinetics. The IMX first combines with PbI2 in the precursor film to form a 2D intermediate which then gradually releases PbI2 to slowly form high‐quality CsPbI2 Br film during annealing. It is found that the LDIAG method produces a uniform, highly crystalline, pinhole‐free, and stable CsPbI2 Br film with low defect density. Consequently, the solar cell efficiency is increased to as high as 17.26%, one of the highest for this type of device. Furthermore, the bare device without any encapsulation shows excellent long‐term stability with ≈86% of its initial efficiency retained after being exposed to the ambient environment for 1000 h. This work provides a perspective to tune the intermediate phases and crystallization pathway for high‐performance inorganic PSCs formed under ambient conditions. Abstract : Herein, a low‐dimensional intermediate‐assisted growth (LDIAG) method is reported to deposit high quality CsPbI2 Br film in ambient atmosphere by introducing imidazolium halide to control both nucleation and growth kinetics. The obtained CsPbI2 Br solar cell shows an efficiency of 17.26% and excellent long‐term stability with ≈86% of its initial efficiency retained after being exposed to the ambient environment for 1000 h.