Photocatalytic Properties of Nitrogen-Doped Bi_(12)TiO_(20) Synthesized by Urea Addition Sol-Gel Method

摘要

Undoped and nitrogen-doped Bi_(12)TiO_(20) materials were synthesized by urea addition sol-gel method. By adding urea, undoped, and N-doped gel-type precursors were synthesized by low-temperature dehydrolyzation. Nitrogen-doped and undoped nanocrystalline Bi_(12)TiO_(20) were prepared by annealing at 600 deg C for 30 minutes. From UV-Vis absorption and diffuse reflection spectrum, the absorbing band shifted from 420 to 500 nm by nitrogen doping. The bonds of Ti-N and N-O were identified by XPS spectra from the prepared materials, and the enhancement of visible light absorption was attributed to nitrogen's substitution of oxygen. Photocatalytic properties of prepared materials were characterized by the decomposition of Rhodamine B illuminated by whole spectra of 300 W Xe light. The photocatalyst Bi_(12)TiO_(20-y)N_(y) (y velence 0.03) with N/(N+O) mole ratio about 3percent shows better performance than that of heavily doped Bi_(12)TiO_(20-z)N_(z) (z velence 0.06), undoped Bi_(12)TiO_(20), and light-doped Bi_(12)TiO_(20-x)N_(x) (x velence 0.01) photocatalysts due to its better crystalline morphology.