Fabricate the Compressive-Strained Perovskite Solar Cells through the Lattice-Matching Chelation

Fabricating compressive-strained perovskite films can boost the efficiency and stability of perovskite solar cells (PSCs). However, compositional engineering toward the conversion of surface tension strain to compressive strain rarely succeeds. Herein, we propose an effective lattice-matching chelation strategy to modulate the strain of the crystal lattice of perovskite films. Detailed investigations show that the organic salt of bidentate imidazole (MZ-1) can firmly anchor the perovskite lattice, resulting in compressive-strained perovskite films, leading to better energy alignment, improved charge carrier transport, decreased nonradiative recombination, and lower trap state density. PSC based on MZ-1 exhibits a dramatically improved efficiency of 24.61% along with improved long-term thermal stability. Importantly, a large -area (25 cm2) integrated module achieves an efficiency of 20.53%.

Automated summary

This study proposes an effective lattice-matching chelation strategy to modulate the strain of perovskite films, leading to improved efficiency and stability of perovskite solar cells. The organic salt of bidentate imidazole is able to anchor the perovskite lattice, resulting in compressive-strained perovskite films and achieving better energy alignment, improved charge carrier transport, decreased nonradiative recombination, and lower trap state density. The perovskite solar cell based on this method exhibits an efficiency of 24.61% and improved long-term thermal stability, while a large-area integrated module achieves an efficiency of 20.53%.