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.