Constructing Hybrid Dimensional Nanowires Array/Nanosheet Heterojunction of GaSb/PbI₂ for Self‐Powered Imaging, Photocommunication, and Omnidirectional Weak‐Light Photodetection

Abstract Interface contact and mismatched photosensitive area are challenging the hybrid dimensional heterojunction self‐powered photodetection. Herein, the hybrid dimensional nanowires (NWs) array/nanosheet (NS) heterojunction of GaSb/PbI 2 is successfully constructed by the combination of contact printing technology and drop‐casting process. Owing to the build‐in electric field, the as‐fabricated NW/NS heterojunction photodetector exhibits enhanced photoresponse compared to NW and NS photodetectors. Moreover, the NWs array/NS heterojunction photodetector shows an ultralow I dark of 1.12 × 10 −13 A, a superior I light /I dark ratio of 1.2 × 10 4 , and ultrafast photoresponse of 232/465 µs. The excellent photodetection performance enables the NWs array/NS hybrid dimensional heterojunction in omnidirectional photodetection, imaging, and photocommunication. Furthermore, the weak‐light detection is also demonstrated successfully even at light intensity as low as 0.06 µW·mm −2 . This work paves the way of constructing hybrid dimensional heterojunction for high‐performance multifunctional self‐powered photodetection.