High-Efficiency Self-Powered Broadband Photodetector Based on PtSe<sub>2</sub>/MoSe<sub>2</sub> Heterojunction
Mengqi Che, Yahui Li, Bin Wang, Jian Yuan, Liujian Qi, Yuting Zou, Mingxiu Liu, Xingyu Zhao, Yaru Shi, Fan Tan, Yanze Feng, Dabing Li, Shaojuan Li
Abstract
Platinum selenide (PtSe 2 ) is a new 2D transition metal dichalcogenide with tunable bandgap, high carrier mobility, and air stability, which has hopeful applications in high-performance photodetectors and microelectronic devices. However, low response and large dark current caused by the semimetal properties of PtSe 2 limit its applications. In this work, a PtSe 2 /MoSe 2 heterojunction photodetector is constructed for high-performance broadband self-powered photodetection. The device exhibits a rectification ratio exceeding 10 5, achieving an ultralow reverse current of 10 –12 A, and superior photovoltaic performance under illumination. The heterojunction photodetector can respond to a broadband spectrum from visible to near-infrared with an external quantum efficiency (EQE) of 64.2%, a photovoltaic responsivity of 275 mA/W, a photovoltaic specific detectivity of 1.96 × 10 11 Jones, and a filling factor of 0.46. In addition, a significant specific detectivity of 1.2 × 10 13 Jones, a high responsivity of 9.02 × 10 3 A/W, and an EQE of 2.1 × 10 7 % were obtained under forward bias (3 V). Moreover, the broadband imaging capability in both biasing and self-powered modes also proves the application potential of the PtSe 2 /MoSe 2 heterojunction photodetector. This work highlights the promising potential of 2D transition metal dichalcogenide for broadband, self-powered, and high-performance photodetection.