Toward Smart SiC Self-Powered Deep Ultraviolet Photodetectors

The reasonable construction of a heterojunction is promising for wide bandgap semiconductors in smart self-powered deep ultraviolet (DUV) photodetection. In this work, PbI₂ nanosheet (NS) is prepared directly on the wide bandgap semiconductor of a SiC wafer for the success construction of a type-II heterojunction by a simple drop-casting method. Benefiting from the built-in electric field at the heterojunction interface, the as-fabricated SiC type-II heterojunction photodetector exhibits enhanced DUV photoresponse compared to the SiC wafer and PbI₂ NS photodetectors. The as-fabricated SiC type-II heterojunction photodetector further exhibits excellent self-powered photodetection behaviors, including the low dark current of 1.3 × 10^-13 A, high I_light/I_dark ratio of 1.5 × 10⁴, and fast response times of 0.65/0.58 ms. The excellent photodetection performance enables the SiC type-II heterojunction in omnidirectional photodetection and photocommunication. This work paves the way of constructing a SiC heterojunction for high-performance DUV self-powered photodetection.