Fabrication of Visible-Light-Driven N-Doped Ordered Mesoporous TiO_2 Photocatalysts and Their Photocatalytic Applications

摘要

Herein we report a facile method for the synthesis of N-doped crystalline mesoporous titanium dioxide (NMT) with ordered structure. Structural characterization and HR-TEM studies revealed that NMT exhibits pure anatase phase with highly crystalline ordered mesoporous structure in NMT. The N_2 isotherms are of type IV with an H1 hysteresis loop and a pronounced capillary condensation step at high relative pressure for NMT, suggesting the presence of well-ordered mesoporous structure. The reflectance spectrum of NMT shows stronger absorption in the visible region above 400 nm, owing to the substitution of the lattice oxygen by nitrogen. XPS results proved the doping of nitrogen in to oxygen in TiO_2 lattice, which confirmed by the presence of peak at 401 eV for N1s. The efficiency of photocatalyst was evaluated by the degradation of Rhodamine-B and antibacterial activity against E. coli under visible-light irradiation. N-doped mesoporous TiO_2 shows superior photocatalytic and anti-bacterial activity compared to pure TiO_2 under visible-light irradiation. The enhanced photocatalytic activity of NMT is attributed to synergistic effect of NMT that is N-doping and well ordered crystalline mesoporous structure with high surface area of NMT. These findings suggest that N-doped mesoporous TiO_2 has potential application in many areas such as degradation of hazardous pollutants, anti-bacterial agents, fuel cells, battery electrode, sensors, opto electronic devices, photo active self-cleaning surfaces.