Pyro‐Phototronic Effect in Two‐Dimensional Graphene/AgCrP 2 S 6 /Graphene Heterojunction
Danzhi Wang, Pengfei Hou, Fenxian Wei, Pan Zhou, Shuoguo YuanABSTRACT
The pyro‐phototronic effect has been identified as a promising strategy for improving the performance of photodetectors. In this study, we report the discovery of the pyro‐phototronic effect in the graphene/AgCrP 2 S 6 /graphene (Gr/AgCrP 2 S 6 /Gr) heterojunction. Multilayer AgCrP 2 S 6 exhibits a non‐centrosymmetric structure induced by interlayer sliding, as experimentally verified by second‐harmonic generation (SHG) and piezoresponse force microscopy (PFM). Furthermore, the fabricated Gr/AgCrP 2 S 6 /Gr heterojunction, which exhibits a peak pyroelectric coefficient of 9638 µC·m −2 ·K −1 . The pyro‐phototronic effect of the heterojunction is systematically investigated under varying wavelengths, optical power intensities, bias voltages, and modulation frequencies. The pyro‐phototronic effect markedly enhances the heterojunction's output current density, achieving a remarkable 14.57‐fold increase relative to the performance based solely on the photovoltaic effect. Specifically, under 405 nm illumination, the heterojunction achieves peak photodetection metrics: responsivity of 46.01 mA/W, external quantum efficiency of 14.09%, and specific detectivity of 2.2 × 10 11 Jones. These findings deepen the understanding of multi‐field coupling mechanisms in 2D materials and establish a new paradigm for the design and development of high‐performance photodetectors leveraging the pyro‐phototronic effect.