Effect of ultraviolet light irradiation on electron field emission from titanium-oxide nanostructures

Field-emission current from titanium-oxide nanostructures is increased by ultraviolet (UV) light irradiation. The field-emission current after UV irradiation was tens of times larger than that before irradiation. The enhancement in electron emission by UV at 365 nm is larger than that at 405 nm. The increased emission current did not decrease after the irradiation was stopped but did decrease after the sample was exposed to air. This suggests that surface cleaning by photon induced reaction is the origin of the observed current enhancement.