Stable Sn/Pb-Based Perovskite Solar Cells with a Coherent 2D/3D Interface

Ziming Chen; Meiyue Liu; Zhenchao Li; Tingting Shi; Yongchao Yang; Hin-Lap Yip; Yong Cao

doi:10.1016/j.isci.2018.11.003

Stable Sn/Pb-Based Perovskite Solar Cells with a Coherent 2D/3D Interface

iScience. 2018 Nov 30:9:337-346. doi: 10.1016/j.isci.2018.11.003. Epub 2018 Nov 4.

Authors

Ziming Chen¹, Meiyue Liu¹, Zhenchao Li¹, Tingting Shi¹, Yongchao Yang¹, Hin-Lap Yip², Yong Cao¹

Affiliations

¹ State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, School of Materials Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou 510640, P. R. China.
² State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, School of Materials Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou 510640, P. R. China; Innovation Center for Printed Photovoltaics, South China Institute of Collaborative Innovation, Dongguan 523808, P. R. China. Electronic address: msangusyip@scut.edu.cn.

Abstract

Low-band-gap metal halide perovskite semiconductor based on mixed Sn/Pb is a key component to realize high-efficiency tandem perovskite solar cells. However, the mixed perovskites are unstable in air due to the oxidation of Sn²⁺. To overcome the stability problem, we introduced N-(3-aminopropyl)-2-pyrrolidinone into the CH₃NH₃Sn_0.5Pb_0.5I_xCl_3-x thin film. The carbonyl group on the molecule interacts with Sn²⁺/Pb²⁺ by Lewis acid coordination, forming vertically oriented 2D layered perovskite. The 2D phase is seamlessly connected to the bulk perovskite crystal, with a lattice coherently extending across the two phases. Based on this 2D/3D hybrid structure, we assembled low-band-gap Sn-based perovskite solar cells with power conversion efficiency greater than 12%. The best device was among the most stable Sn-based organic-inorganic hybrid perovskite solar cells to date, keeping 90% of its initial performance at ambient condition without encapsulation, and more than 70% under continuous illumination in an N₂-filled glovebox for over 1 month.

Keywords: Energy Materials; Materials Science; Optical Materials.