PbI2 / Pb5S2 I6 van der Waals Heterojunction Photodetector.

Investigations of two-dimensional ( 2D ) / one-dimensional ( 1D) van der Waals ( vdW) heterojunctions have attracted significant attention due to their excellent properties such as the smooth heterointerface, the highly gate-tunable bandgap, and the ultrafast carrier transport. However, the complicated method of manufacturing vdW heterojunction represents a major problem that severely limits their practical applications. Herein, we develop onestep hydrothermal method and use it to synthesize 2D PbI₂ / 1D Pb₅S₂I₆ vdW heterojunction. The PbI₂ / Pb₅S₂I₆ vdW heterojunction photodetector(PD) displays lower dark current (<20 pA), higher responsivity (up to 134 mA·W^-1), self-powered and wider response spectrum in comparison with that of pristine PbI₂ PD and Pb₅S₂I₆ PD. This one-step hydrothermal method provides a new idea for preparing other mixed-dimensional heterojunction. [ABSTRACT FROM AUTHOR]