Iodine reduction for reproducible and high-performance perovskite solar cells and modules

Shangshang Chen; Xun Xiao; Hangyu Gu; Jinsong Huang

doi:10.1126/sciadv.abe8130

Iodine reduction for reproducible and high-performance perovskite solar cells and modules

Sci Adv. 2021 Mar 3;7(10):eabe8130. doi: 10.1126/sciadv.abe8130. Print 2021 Mar.

Authors

Shangshang Chen¹, Xun Xiao¹, Hangyu Gu¹, Jinsong Huang²

Affiliations

¹ Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC 27599, USA.
² Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC 27599, USA. jhuang@unc.edu.

Abstract

Perovskite-based electronic materials and devices such as perovskite solar cells (PSCs) have notoriously bad reproducibility, which greatly impedes both fundamental understanding of their intrinsic properties and real-world applications. Here, we report that organic iodide perovskite precursors can be oxidized to I₂ even for carefully sealed precursor powders or solutions, which markedly deteriorates the performance and reproducibility of PSCs. Adding benzylhydrazine hydrochloride (BHC) as a reductant into degraded precursor solutions can effectively reduce the detrimental I₂ back to I^-, accompanied by a substantial reduction of I₃ ^--induced charge traps in the films. BHC residuals in perovskite films further stabilize the PSCs under operation conditions. BHC improves the stabilized efficiency of the blade-coated p-i-n structure PSCs to a record value of 23.2% (22.62 ± 0.40% certified by National Renewable Energy Laboratory), and the high-efficiency devices have a very high yield. A stabilized aperture efficiency of 18.2% is also achieved on a 35.8-cm² mini-module.

Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).