LAUSR

Flexible UV photodetector with high on/off ratio is extremely important for environmental sensing, optical communication and flexible optoelectronic devices. In this work, a flexible fiber-based UV photodetector with ultrahigh on/off ratio is developed by utilizing the synergism between interface and surface gating effects on ZnO nanowire network structure. The synergism of two gating effects is realized by the interplay of surface band bending and the Fermi level through nanowire-network structure, which is proved through the control experiments between ZnO micro/nanowire photodetector and micro/nanowire-junction photodetector, and the corresponding KPFM measurements. The on/off ratio of fiber-based ZnO nanowire-network UV photodetector reaches 1.98×108 when illuminated by 1.0 mW cm-2 UV light, which is 20 times larger than the largest reported result under the same UV illumination. This new UV sensor also has the high resolution to UV light intensity change in nW cm-2 range. Furthermore, when the fiber-based photodetector is curved, it still shows the excellent performance as above. This work gives a new effective route for the development of high-performance UV photodetector or other optoelectronic detection devices.