WSe2/ReS2 heterojunction for high-temperature photodetectors with high sensitivity and fast response

Abstract

Breakthroughs in aerospace engineering, deep-well drilling, and harsh-environment robotics have fueled demand for thermally stable photodetectors. 2D material-based detectors show promise in delivering high-sensitivity, low-power nano-integration under extreme conditions through tunable band structures and interlayer charge dynamics. This work demonstrates a semi-vertical ReS₂/WSe₂ heterojunction photodetector in air with exceptional high-temperature stability (373–473 K) and broadband sensitivity from ultraviolet (UV) to visible light. The sensitivity of the device increases and then decreases from room temperature to 473 K, reaching a maximum at 373 K. At 373 K, the self-powered device exhibits a responsivity (R) of 0.145 A/W, a specific detectivity (D*) of 1.36 × 10 ¹ ² Jones, and an external quantum efficiency (EQE) of 55.71 % under UV illumination (325 nm), while under visible light (532 nm), it achieves R of 0.0134 A/W, D* of 2.85 × 10 ¹ ⁰ Jones, and EQE of 3.13 %. Applying a 1 V bias further enhances the UV performance at 373 K, elevating R to 121.4 A/W, D* to 1.615 × 10 12 Jones, and EQE to 4.65 × 10⁴ %. At 473 K, the device retains R of 29.2 A/W and D* of 8.82 × 10 ¹ ¹ Jones, with EQE of 1.12 × 10⁴ %. In addition, the device shows an ultrafast response time of 5.2/3.9 μs at 373 K and demonstrates stable operation at 473 K in air. This work advances high-temperature photodetection for applications in extreme environments. • A semi-vertical ReS 2 /WSe 2 vdW heterojunction photodetector enables dual-mode (photovoltaic/photoconductive) operation. • Revealing that ReS 2 /WSe 2 heterojunction photodetectors can work stably at high temperatures (373–473 K). • Achieving high responsivity, ultrafast, broadband and self-powered photodetectors under 373 K. • Systematically elucidates the temperature-dependent operational mechanisms of the ReS₂/WSe₂ heterojunction.