催化学报

催化学报 ›› 2011, Vol. 32 ›› Issue (8): 1430-1435.DOI: 10.3724/SP.J.1088.2011.10431

• 研究论文 • 上一篇    

新型 N-TiO2 的固相法制备及其光催化性能

马鹏举, 闫国田, 钱俊杰, 张敏, 杨建军*   

  1. 河南大学特种功能材料教育部重点实验室, 河南开封 475004
  • 收稿日期:2011-04-19 修回日期:2011-06-10 出版日期:2011-08-05 发布日期:2014-12-26

Preparation of Novel N-TiO2 by a Solid-State Method and Its Photocatalytic Activity

MA Pengju, YAN Guotian, QIAN Junjie, ZHANG Min, YANG Jianjun*   

  1. Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004, Henan, China
  • Received:2011-04-19 Revised:2011-06-10 Online:2011-08-05 Published:2014-12-26

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摘要： 以纳米管钛酸为前驱体, 以 NH4HCO3 为 N 源, 先机械研磨使二者混合均匀, 再在 Ar 保护下, 于不同温度焙烧 4 h 制得 N 掺杂 TiO2 (N-TiO2), 并采用 X 射线粉末衍射、X 射线光电子能谱、紫外-可见吸收光谱、透射电镜及 N2 吸附-脱附对样品进行了表征. 结果显示, N 以间隙掺杂方式进入 TiO2 晶格内. 在热处理过程中, 生成中间体 (NH4)2Ti2O4(OH)2, 它不仅可在升温过程中缓慢分解并释放出 N, 使其更均匀地进入 TiO2, 同时可产生更多的氧空位, 显著提高了 N-TiO2 对光的响应能力. 另外, N 的掺杂可抑制 N-TiO2 锐钛矿相向金红石相转化. 当焙烧温度为 500 °C, n(N)/n(Ti) = 4 时, 所制 N-TiO2 样品经光照 130 min, 可使甲基橙完全降解, 其活性比未掺杂 N 的样品提高近 30%.

关键词: 氮掺杂, 固相法, 光催化, 纳米管钛酸, 纳米管钛酸盐

Abstract: N-doped TiO2 photocatalyst samples were prepared by manual grinding the mixture of nanotube titanic acid and ammonium bicarbonate followed by annealing the mixture at different temperatures in Ar atmosphere for 4 h. The samples were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy (XPS), UV-Vis spectrophotometry, transmission electron microscope, and N2 adsorption-desorption. The XPS results indicated that the N was in the form of interstitial atom, i.e., Ti–O–N bond. The intermediate (NH4)2Ti2O4(OH)2 was formed when the mixture was calcined at different temperatures. Subsequently, the N was released due to the decomposition of (NH4)2Ti2O4(OH)2, resulting in the formation of interstitial-N and oxygen vacancies. N-TiO2 samples showed enhanced visible light absorption and visible light photocatalytic activity because of the existence of interstitial N-dopants and oxygen vacancies. The doped N atoms restrained the phase transition from anatase to rutile at higher temperature. Photocatalytic activity was evaluated by degradation of methyl orange in aqueous solution under xenon lamp irradiation, and the N-TiO2 sample with n(N)/n(Ti) = 4 annealed at 500 °C exhibited the highest photocatalytic activity. After 130 min irradiation, the photocatalytic degradation rate of methyl orange was up to 100%, almost 30% higher than that of un-doped TiO2.

Key words: nitrogen doping, solid state method, photocatalysis, nanotube titanic acid, nanotube titanate