不同氮源溶剂热合成N-TiO2纳米颗粒及其光催化降解气相苯（英文）

采用三种不同的氮源溶剂热合成了锐钛矿-板钛矿混晶的N-TiO2催化剂.采用X射线衍射、N2吸附-脱附、X射线光电子能谱和透射电子显微镜等手段对催化剂进行了表征.重点研究了不同氮源对催化剂的相组成、晶粒尺寸、微观结构以及比表面积的影响.采用紫外光降解气相苯测试了合成材料的催化活性.结果表明,以水合肼为氮源合成的N-TiO2表现出最优的光催化活性,其活性明显高于P25,且能够循环使用15次以上.采用气相色谱-质谱技术分析了光降解过程的中间产物,基于此提出了相应的降解机理.

Solvothermal synthesis of N-doped TiO2 nanoparticles using different nitrogen sources,and their photocatalytic activity for degradation of benzene

Anatase-brookite mixed-phase N-doped TiO₂ (N-TiO₂) nanoparticles were synthesized through a solvothermal method using different nitrogen sources. The resulting samples were characterized by X-ray diffraction, specific surface area measurement, X-ray photoelectron spectroscopy, and standard and high-resolution transmission electron microscopy. The effects of the different nitrogen sources on phase composition, particle size, microstructure, and specific surface area are investigated. The photocatalytic activity of the TiO₂ samples was evaluated through photocatalytic degradation of gaseous benzene under UV-light irradiation. N-TiO₂ prepared using hydrazine hydrate achieved the highest photocatalytic performance in all the samples studied (including the commercial P25). Different intermediates during the photocatalytic degradation of benzene over HNT were identified by GC-MS analysis. A detailed reaction mechanism was proposed to explain their formation as intermediates in the reaction. Moreover, the photocatalytic activity of the nanoparticles remained almost unchanged after 15 gaseous-benzene degradation test cycles.