Vapor-assisted deposition of highly efficient, stable black-phase FAPbI3 perovskite solar cells

Haizhou Lu; Yuhang Liu; Paramvir Ahlawat; Aditya Mishra; Wolfgang R Tress; Felix T Eickemeyer; Yingguo Yang; Fan Fu; Zaiwei Wang; Claudia E Avalos; Brian I Carlsen; Anand Agarwalla; Xin Zhang; Xiaoguo Li; Yiqiang Zhan; Shaik M Zakeeruddin; Lyndon Emsley; Ursula Rothlisberger; Lirong Zheng; Anders Hagfeldt; Michael Grätzel

doi:10.1126/science.abb8985

Vapor-assisted deposition of highly efficient, stable black-phase FAPbI₃ perovskite solar cells

Science. 2020 Oct 2;370(6512):eabb8985. doi: 10.1126/science.abb8985.

Authors

Haizhou Lu^{1

2}, Yuhang Liu², Paramvir Ahlawat³, Aditya Mishra⁴, Wolfgang R Tress¹, Felix T Eickemeyer², Yingguo Yang⁵, Fan Fu⁶, Zaiwei Wang¹, Claudia E Avalos⁴, Brian I Carlsen¹, Anand Agarwalla¹, Xin Zhang⁷, Xiaoguo Li⁷, Yiqiang Zhan⁸, Shaik M Zakeeruddin², Lyndon Emsley⁴, Ursula Rothlisberger³, Lirong Zheng⁸, Anders Hagfeldt⁹, Michael Grätzel¹⁰

Affiliations

¹ Laboratory of Photomolecular Science, Institute of Chemical Sciences Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
² Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, EPFL, CH-1015 Lausanne, Switzerland.
³ Laboratory of Computational Chemistry and Biochemistry, Institute of Chemical Sciences and Engineering, EPFL, CH-1015 Lausanne, Switzerland.
⁴ Laboratory of Magnetic Resonance, Institute of Chemical Sciences and Engineering, EPFL, CH-1015 Lausanne, Switzerland.
⁵ Shanghai Synchrotron Radiation Facility (SSRF), Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, P. R. China.
⁶ Laboratory for Thin Films and Photovoltaics, Empa-Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Duebendorf, Switzerland.
⁷ Centre for Micro Nano Systems, School of Information Science and Technology (SIST), Fudan University, Shanghai 200433, P. R. China.
⁸ Centre for Micro Nano Systems, School of Information Science and Technology (SIST), Fudan University, Shanghai 200433, P. R. China. yqzhan@fudan.edu.cn lrzheng@fudan.edu.cn anders.hagfeldt@epfl.ch michael.graetzel@epfl.ch.
⁹ Laboratory of Photomolecular Science, Institute of Chemical Sciences Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland. yqzhan@fudan.edu.cn lrzheng@fudan.edu.cn anders.hagfeldt@epfl.ch michael.graetzel@epfl.ch.
¹⁰ Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, EPFL, CH-1015 Lausanne, Switzerland. yqzhan@fudan.edu.cn lrzheng@fudan.edu.cn anders.hagfeldt@epfl.ch michael.graetzel@epfl.ch.

PMID: 33004488
DOI: 10.1126/science.abb8985

Abstract

Mixtures of cations or halides with FAPbI₃ (where FA is formamidinium) lead to high efficiency in perovskite solar cells (PSCs) but also to blue-shifted absorption and long-term stability issues caused by loss of volatile methylammonium (MA) and phase segregation. We report a deposition method using MA thiocyanate (MASCN) or FASCN vapor treatment to convert yellow δ-FAPbI₃ perovskite films to the desired pure α-phase. NMR quantifies MA incorporation into the framework. Molecular dynamics simulations show that SCN^- anions promote the formation and stabilization of α-FAPbI₃ below the thermodynamic phase-transition temperature. We used these low-defect-density α-FAPbI₃ films to make PSCs with >23% power-conversion efficiency and long-term operational and thermal stability, as well as a low (330 millivolts) open-circuit voltage loss and a low (0.75 volt) turn-on voltage of electroluminescence.

Publication types

Research Support, Non-U.S. Gov't

Grants and funding

SNSF_/Swiss National Science Foundation/Switzerland