通过XRD、TEM、DRS、XPS等技术研究了纳米TiO2粉末在不同气氛中进行热处理的晶体结构, 形貌及价态分布等. 结果表明, 在氮气中较低温度(400℃)热处理后发生了由锐钛矿向金红石的转变, 颗粒分布均匀, 并且由于部分N原子进入表面的TiO2晶格中取代了部分O原子产生氧缺陷, 从而成为光活性中心, 致使吸收光子的数量增多, 带隙变宽, 并向可见光区方向移动. 光催化降解亚甲基蓝溶液实验也表明在氮气中热处理较大提高了纳米TiO2粉末可见光光催化活性.
The nano-TiO2 powders were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), diffuse reflectance spectra (DRS) and X-ray photoelectron spectroscope (XPS). The results show that nano-TiO2 is transformed to rutile crystal after treating at 400℃ in N2 atmosphere and the nano-TiO2 particles obtained are uniform. Part N atoms are intruded into the TiO2 crystals and substituted for some of O atoms, which produce oxygen defects. Those oxygen defects become the center of photo activity, which result in the increase of absorbed photons and the formation of broad band gap and make the absorption spectrum move to the visible light. The photocatalytic degradation of methylene blue shows that the visible light catalytic activity of nano-TiO2 calcined in N2 atmosphere is improved.
参考文献
| [1] | Park H, Choi W. J. Phys. Chem. B, 2003, 107 (16): 3885-3890. [2] Yu J C, Lin Jun, Lin D, et al. Langmuir, 2000, 16 (18): 7304-7308. [3] Watanabe T, Kitamura A, Kojima E, et al. Photocatalytic purification and treatment of water and air. Amsterdam: Elsevier, 1993. 747-748. [4] Linsebigler A L, Lu G Q, Yates J T. Chem. Rev., 1995, 95 (3): 735-758. [5] Rusu C N, Yates J T. Langmuir, 1997, 13 (16): 4311-4318. [6] Sato S, Kadowaki T, Yamaguti K. J. Phys. Chem., 1984, 88 (14): 2930-2931. [7] 周武艺, 曹庆云, 唐绍裘, 等(ZHOU Wu-Yi, et al). 无机材料学报 (Journal Inorganic Materials), 2006, 21 (4): 776-782. [8] Lettmann C, Heike H, Maier W F. Angew. Chem. Int. Ed., 2001, 40 (17): 3160-3164. [9] Balachandran U, Eror N G. J. Solid State Chem., 1982, 42 (2): 276-282. [10] 李国华, 王大伟, 徐铸德( LI Guo-Hua, et al). 无机材料学报(Journal of Inorganic Materials), 2002, 17 (3): 422-428. [11] Bersani D, Antonioli G, Paolo P, et al. J. Non-Cryst. Solids, 1998, 232/234: 175-181. [12] Asahi R, Morikawa T, Ohwaki T, et al. Science, 2001, 293 (5528): 269-271. [13] Ihara T, Miyoshi M, Iriyama Y, et al. Appl. Catal. B: Environ., 2003, 42 (4): 403-409. [14] Yang M C, Yang T S, Wong M S. Thin Solid Film, 2004, 469/470 (12): 1-5. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%