Molecularly Engineered Self-Healing Scaffold With Customized Dynamic Bonds Enable Stable and Scalable Flexible Perovskite Solar Cells and Modules.

Abstract

Organometallic halide perovskites hold great promise as materials for high-performance flexible perovskite solar cells (f-PSCs). However, achieving uniform, highly crystalline, and mechanically robust perovskite films remains a critical challenge for f-PSCs. Here, a tandem dynamic bond-based monomer (ADM) was incorporated into a perovskite film, where it cross-links in situ to control nucleation and crystallization. This enables multi-modal passivation via Lewis-base coordination and hydrogen bonding between ADM and the perovskite lattice. The tandem dynamic bonds within the cross-linked network, preferentially residing at grain boundaries, endow the flexible perovskite films with an instantaneous self-curing capability under mild treating conditions (40°C for 30 min). As a result, champion devices deliver a power conversion efficiency (PCE) of 27.12% (certified 26.80%) for small-area rigid PSCs and 20.00% for a flexible minimodule (10.24 cm²), while a large-area inverted perovskite submodule with an active area of 655.2 cm² achieves a record-breaking PCE of 21.60% and a certified efficiency of 20.37%, demonstrating excellent scalability. Critically, the intrinsic self-healing capability underpins exceptional mechanical endurance, allowing the devices to maintain more than 91% of their original PCE after 10 000 bending cycles.