Heterostructured ZnS/InP nanowires for rigid/flexible ultraviolet photodetectors with enhanced performance.

Heterostructured ZnS/InP nanowires, composed of single-crystalline ZnS nanowires coated with a layer of InP shell, were synthesized via a one-step chemical vapor deposition process. As-grown heterostructured ZnS/InP nanowires exhibited an ultrahigh Ion/Ioff ratio of 4.91 × 103, a high photoconductive gain of 1.10 × 103, a high detectivity of 1.65 × 1013 Jones and high response speed even in the case of very weak ultraviolet light illumination (1.87 μW cm-2). The values are much higher than those of previously reported bare ZnS nanowires owing to the formation of core/shell heterostructures. Flexible ultraviolet photodetectors were also fabricated with the heterostructured ZnS/InP nanowires, which showed excellent mechanical flexibility, electrical stability and folding endurance besides excellent photoresponse properties. The results elucidated that the heterostructured ZnS/InP nanowires could find good applications in next generation flexible optoelectronic devices.