High performance self-powered and broadband photodetector based on 1T/2H MoS2 Schottky homojunction

Abstract

All-2D van der Waals (vdW) Schottky heterojunctions provide a new platform for constructing the self-powered photo detector. However, the sophisticated process flow and unintentional introduction of structural defects can severely degrade the device's performance. In this work, a novel Schottky homojunction based on self-assembled 1T/2H MoS₂ was reported. Experimental results evidenced that the photo detector exhibited self-powered characteristics. The photovoltaic effects could be observed across a broad spectrum ranging from 380 to 900 nm. Moreover, responsivities (R) of 24.5 mA/W, 29.5 mA/W, and 89 mA/W, and detectivities (D∗) of 1.37 × 10¹¹ Jones, 1.65 × 10¹¹ Jones, and 4.98 × 10¹¹ Jones, under UV (380 nm), visible light (550 nm), and near-infrared (900 nm) light, could be achieved, respectively. And excellent switching response times of 6.2 m s (raise time) and 5 m s (fall time) were also recorded. These results evidence that the Schottky homojunction can be an attractive approach for developing high performance optoelectronic detectors.