Single ZnO Nanowire/p-type GaN Heterojunctions for Photovoltaic Devices and UV Light-Emitting Diodes

We fabricate heterojunctions consisting of a single n-type ZnO nanowire and a p-type GaN film. The photovoltaic effect of heterojunctions exhibits open-circuit voltages ranging from 2 to 2.7 V, and a maximum output power reaching 80 nW. Light-emitting diodes with UV electroluminescence based on the heterojunctions are demonstrated.