Flexible, active P-typed copper(I) thiocyanate (p-CuSCN) films as self-powered photodetectors for large-scale optoelectronic systems

Abstract

P-type copper(I) thiocyanate (p-CuSCN) semiconductor materials have attracted a great deal of attention in the application for microsystems and optoelectronic engineering. Major challenge is in the development of advanced fabrication/growth techniques and resultant high-efficiency devices. Herein, in situ grown p-CuSCN film with different morphology are successfully achieved on flexible Cu foil by the simple solid-liquid interface reaction, which displays excellent UV photoresponse due to effective charge transport, thereby contributing to the large-area fabrication technique and the high-performance operation. The self-powered, highly sensitive and flexible NGQDs/CuSCN heterojunction device shows the ultrahigh photoresponsivity of 1.6 A/W and detectivity of 0.8 × 10¹² Jones at 3 V bias under 360 nm illumination, and the ultrafast photoresponse speed (T_r= 10 µs, T_d=0.6 ms), with relatively stable performance under bending cycles. The results provides an easy-processing and promising route to fabricate large-area p-CuSCN with remarkable optoelectronic performance, which opens up a new avenue on more novel works for the material design in practical photodetection.