Vertically Stacked Au/PbS/CsPbCl<sub>3</sub> Phototransistors for Plasmon-Enhanced High-Performance Broadband Photodetection
Kai Li, Xinhong Zhao, Yongchu Fang, Yu Tao, Xiaoxian Song, Haiting Zhang, Huaqing Yu, Peng Wang
Abstract
All inorganic perovskites have been regarded as attractive optoelectronic materials due to their tunable properties, good stability, and low-temperature processing techniques. However, the relatively low responsivity and narrow response range still hinder their potential for optoelectronic applications. In this work, vertically stacked Au/PbS/CsPbCl3 phototransistors were fabricated by a low-temperature solution method. The phototransistors achieved a wide spectral photodetection of 300–1100 nm. The phototransistors had an effective electron mobility of 654.75 cm2/V s without light illumination. Under 532 nm incident light, due to the enhancement of plasmonic Au nanoparticles, the phototransistors demonstrated a remarkable responsivity of 3892 A/W, a high detectivity of 3.29 × 1013 Jones, as well as an ultrahigh external quantum efficiency of 106%. In addition, the phototransistors also exhibited excellent stability in air. The results demonstrate that a vertically stacked Au/PbS/CsPbCl3 architecture is a promising candidate for broadband photodetection.