Room temperature one-step synthesis of microarrays of N-doped flower-like anatase TiO_2 composed of well-defined multilayer nanoflakes by Ti anodization

摘要

Microarrays of N-doped flower-like TiO_2 composed of well-defined multilayer nanoflakes were synthesized at room temperature by electrochemical anodization of Ti in NH4F aqueous solution. The TiO_2 flowers were of good anatase crystallinity. The effects of anodizing time, applied voltage and NH_4F concentration on the flower-like morphology were systematically examined. It was found that the morphologies of the anodized Ti were related to the anodizing time and NH_4F concentration. The size and density of the TiO_2 flowers could be tuned by changing the applied voltage. The obtained N-doped flower-like TiO_2 microarrays exhibited intense absorption in wavelengths ranging from 320 to 800nm. Under both UV and visible light irradiation, the photocatalytic activity of the N-doped flower-like TiO_2 microarrays in the oxidation of methyl orange showed a significant increase compared with that of commercial P25 TiO_2 film