Iodide/triiodide redox shuttle-based additives for high-performance perovskite solar cells by simultaneously passivating the cation and anion defects

Huimin Xiang; Jingsheng He; Ran Ran; Wei Zhou; Wei Wang; Zongping Shao

doi:10.1039/d2nr06710b

Iodide/triiodide redox shuttle-based additives for high-performance perovskite solar cells by simultaneously passivating the cation and anion defects

Nanoscale. 2023 Mar 2;15(9):4344-4352. doi: 10.1039/d2nr06710b.

Authors

Huimin Xiang¹, Jingsheng He¹, Ran Ran¹, Wei Zhou¹, Wei Wang¹, Zongping Shao^{1

2}

Affiliations

¹ State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, China. wangwei@njtech.edu.cn.
² WA School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, Perth, WA 6845, Australia.

PMID: 36757208
DOI: 10.1039/d2nr06710b

Abstract

Halide perovskite solar cells (PSCs) have received remarkably increasing interests due to their facile fabrication procedures, use of cost-effective raw materials, and high power conversion efficiencies (PCEs) during the past 10 years. Nevertheless, the state-of-the-art organic-inorganic PSCs suffer from high defect concentration and inferior humid/thermal stability, significantly restricting the widespread applications of PSCs. More specifically, point defects including metallic lead (Pb⁰) and halide iodine (I⁰) are easily generated in Pb/I-based PSCs during fabrication processes and operational conditions due to the inferior interaction between the anions and cations in halide perovskites and promote detrimental carrier recombination and ion migration, leading to inferior PCEs and durability of the PSCs. Herein, to tackle the above-mentioned issues, iodide/triiodide (I^-/I₃^-) redox shuttles as a new additive were introduced to simultaneously passivate the cation and anion defects of methylammonium lead iodide (MAPbI₃)-based PSCs. In particular, I^-/I₃^- redox shuttles play a vital role in regenerating the cation (Pb⁰) and anion (I⁰) defects through the redox cycles of Pb⁰/Pb²⁺ and I⁰/I^-. Consequently, the cell with an optimized amount of I^-/I₃^- additive generated a superior PCE of 20.4%, which was 12% higher than the pristine device (18.2%). Furthermore, the introduction of the I^-/I₃^- additive remarkably improved the humid and thermal stability of MAPbI₃-based PSCs. This work manifests the importance of the design of redox shuttle-based additives to boost the efficiency and durability of organic-inorganic PSCs.