Weak Hydrogen Bond with Iodide Modulating Crystallization of Methylammonium Lead Iodide for High-Performance Perovskite Solar Cells

TL;DR

A weak hydrogen bond involving iodide improves the crystallization of perovskite films, leading to more efficient and stable solar cells.

Contribution

A novel use of weak hydrogen bonds between MAI and glycerol to enhance perovskite film quality and solar cell performance.

Findings

Glycerol incorporation increases grain size and reduces carrier recombination in perovskite films.

Glycerol-doped solar cells achieved a power conversion efficiency of 16.84%.

The solar cells retained 92.05% of their initial efficiency after 30 days of storage.

Abstract

The weak hydrogen bond with methylammonium iodide (MAI) dominates the formation of methylammonium lead iodide (MAPbI3) during its nucleation and growth process. Herein, a weak hydrogen bond involving iodide is designed between the MAI and glycerol molecule in mixed solvents containing N, N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) to delay the growth of MAPbI3 film. Incorporation of glycerol into the perovskite film indicates a larger grain size and suppressed nonradiative recombination of carriers in the film. Finally, the glycerol-doped perovskite solar cells (PSCs) achieve a champion power conversion efficiency (PCE) of up to 16.84%, with excellent stability to retain 92.05% of their initial PCE after 30 days of storage. The above results unveil a deep understanding of weak hydrogen bonds in high-performance perovskite photovoltaics.

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