Ultrasensitive solution-processed perovskite hybrid photodetectors

Abstract

In this work, we demonstrate high performance photodetectors based on organometal halide perovskite materials in a “conventional” device architecture. Due to the excellent intrinsic optical and electrical properties of perovskite materials, high photoresponsivities from 375 nm to 800 nm were obtained. By additionally modifying a sol–gel processed TiO₂ compact layer with a solution-processed [6,6]-phenyl-C₆₁-butyric acid methyl ester (PC₆₁BM), the performance of the perovskite photodetectors is further improved through simultaneously enhancing the photocurrent via facilitating the charge carrier transport at the CH₃NH₃PbI₃/PC₆₁BM interfaces, and suppressing the dark current densities by passivating the inhomogeneous TiO₂ film. As a result, external quantum efficiencies over 80% and detectivities greater than 4 × 10¹² cm Hz^1/2 W⁻¹ are obtained from 375 nm to 800 nm. In addition, on account of the “conventional” structure of the device, as well as the low-temperature solution-processed nature of each layer, our perovskite photodetectors exhibit much superior compatibility with large-scale commercialization methods.