氮掺杂纳米TiO_2的制备与表征

PREPARATION AND CHARACTERIZATION OF N-DOPED NANO-TiO_2

采用溶胶凝胶法制备TiO2前驱体,分别在氮气和空气中,不同温度和时间条件下焙烧,制备纳米TiO2。研究了气氛、温度、时间对TiO2晶相、平均粒径、吸收波长、表面元素组成等的影响。结果表明,氮气中焙烧制备的TiO2比同样条件下在空气中焙烧制备的样品具有更高的相转变温度、更小的晶体平均粒径、更高的表面吸附氧和间隙态N含量、更长的吸收波长。氮气中550℃焙烧4 h制备的TiO2吸收波长达435 nm。

N-doped nano-TiO2 was obtained by calcining in N2 the precursors prepared by the sol-gel method. The N- doped nano-TiO2 was characterized by XRD, XPS, TEM and ultraviolet-visible light spectrometry. The influence of environment atmosphere, calcining temperature and duration on the crystal phase, average crystal diameter, adsorp- tion wave length, contents of surface O, N of N-doped nano-TiO2 were studied and compared with that of TiO2 pre- pared by the same method and under same conditions but calcined in the air. Results showed that N-doped nano-TiO2 has a higher phase transition temperature, higher contents of surface O, higher contents of interstitial N, smaller average crystal size and longer adsorption wave length, which is 435 nm for the sample calcined in N2 for 4 hours at 550 ℃.