Room-temperature photoluminescence (PL) in V2O5 nanospheres with zero-like dimensional structure was investigated. A large number of V4+ oxidation states in the nanospheres were observed by X-ray photoelectron spectroscopy (XPS) measurements. The nanospheres revealed high PL intensity compared with previous studies. In particular, they showed intense ultraviolet (UV) PL near a wavelength of 396 nm (3.13 eV). The intense UV PL was attributed to the enhanced transition probability due to the large number of V4+ (3d1) oxidation states. The PL properties showed strong dependencies on the oxidation states and their distribution.
