A polymer scaffold for self-healing perovskite solar cells

TLDR

Advancing lead‑halide perovskite solar cells toward the market requires large‑scale devices with high efficiency, reproducibility, stability, low‑cost fabrication, and humidity resistance for long‑term operation. The study aims to develop a uniform perovskite film using a novel polymer‑scaffold architecture processed at mild temperatures. This is achieved by employing a mild‑temperature process to fabricate the polymer‑scaffolded perovskite film. The resulting devices reach ~16 % efficiency with minimal variation, maintain high output for 300 h at 70 % RH, recover power conversion efficiency after exposure to water vapor, and demonstrate strong humidity resistance and self‑healing, underscoring the commercial potential of the inexpensive, long‑chain hygroscopic polymer scaffold.

Abstract

Advancing of the lead halide perovskite solar cells towards photovoltaic market demands large-scale devices of high-power conversion efficiency, high reproducibility and stability via low-cost fabrication technology, and in particular resistance to humid environment for long-time operation. Here we achieve uniform perovskite film based on a novel polymer-scaffold architecture via a mild-temperature process. These solar cells exhibit efficiency of up to ∼ 16% with small variation. The unencapsulated devices retain high output for up to 300 h in highly humid environment (70% relative humidity). Moreover, they show strong humidity resistant and self-healing behaviour, recovering rapidly after removing from water vapour. Not only the film can self-heal in this case, but the corresponding devices can present power conversion efficiency recovery after the water vapour is removed. Our work demonstrates the value of cheap, long chain and hygroscopic polymer scaffold in perovskite solar cells towards commercialization.