High-Performance Flexible Photodetectors based on High-Quality Perovskite Thin Films by a Vapor–Solution Method

Organometal halide perovskites are new light-harvesting materials for lightweight and flexible optoelectronic devices due to their excellent optoelectronic properties and low-temperature process capability. However, the preparation of high-quality perovskite films on flexible substrates has still been a great challenge to date. Here, a novel vapor–solution method is developed to achieve uniform and pinhole-free organometal halide perovskite films on flexible indium tin oxide/poly(ethylene terephthalate) substrates. Based on the as-prepared high-quality perovskite thin films, high-performance flexible photodetectors (PDs) are constructed, which display a nR value of 81 A W⁻¹ at a low working voltage of 1 V, three orders higher than that of previously reported flexible perovskite thin-film PDs. In addition, these flexible PDs exhibit excellent flexural stability and durability under various bending situations with their optoelectronic performance well retained. This breakthrough on the growth of high-quality perovskite thin films opens up a new avenue to develop high-performance flexible optoelectronic devices.