Mixed-Organic-Cation Tin Iodide for Lead-Free Perovskite Solar Cells with an Efficiency of 8.12

Ziran Zhao; Feidan Gu; Yunlong Li; Weihai Sun; Senyun Ye; Haixia Rao; Zhiwei Liu; Zuqiang Bian; Chunhui Huang

doi:10.1002/advs.201700204

Mixed-Organic-Cation Tin Iodide for Lead-Free Perovskite Solar Cells with an Efficiency of 8.12

Adv Sci (Weinh). 2017 Jul 14;4(11):1700204. doi: 10.1002/advs.201700204. eCollection 2017 Nov.

Authors

Ziran Zhao¹, Feidan Gu¹, Yunlong Li¹, Weihai Sun^{1

2}, Senyun Ye¹, Haixia Rao¹, Zhiwei Liu¹, Zuqiang Bian¹, Chunhui Huang¹

Affiliations

¹ Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 P. R. China.
² Institute of Modern Optics and State Key Laboratory for Artificial Microstructure and Mesoscopic PhysicsSchool of Physics Peking University Beijing 100871 P. R. China.

Abstract

In this work, a fully tin-based, mixed-organic-cation perovskite absorber (FA) _x (MA)_1-_x SnI₃ (FA = NH₂CH = NH₂⁺, MA = CH₃NH₃⁺) for lead-free perovskite solar cells (PSCs) with inverted structure is presented. By optimizing the ratio of FA and MA cations, a maximum power conversion efficiency of 8.12% is achieved for the (FA)_0.75(MA)_0.25SnI₃-based device along with a high open-circuit voltage of 0.61 V, which originates from improved perovskite film morphology and inhibits recombination process in the device. The cation-mixing approach proves to be a facile method for the efficiency enhancement of tin-based PSCs.

Keywords: cation mixing; lead‐free; perovskite solar cells; power‐conversion efficiency; tin‐based perovskites.