Enhanced UV-C Detection of Perovskite Photodetector Arrays via Inorganic CsPbBr_3 Quantum Dot Down-Conversion Layer

摘要

Organometal halide perovskites have been considered as promising candidates for high-performance low-cost photodetectors. Nonetheless, as perovskite photodetectors are usually built on glass or polymer substrates, their UV-C (200-280 nm) photodetection ability is quite limited due to the high absorption of glass or polymer substrates. Here, a uniform UV photodetector array which integrates perovskite photodiodes with inorganic CsPbBr3 quantum dot (QD) fluorophor is reported. CsPbBr3 quantum dot fluorophor not only acts as an efficient down-conversion layer to convert UV light into 510 nm light, but also functions as a protective layer to prevent degradation of hybrid organic-inorganic perovskite by UV light. Compared to direct UV-C (279 nm) detection with perovskite photodiode, the QD integrated photodetector shows a higher responsibility and detectivity to UV-C, with values enhanced by 1 order in magnitude. This work provides a low-cost and effective approach for all perovskite-based UV-C photodetectors and imagers.