Yuan Fang, Li Chunquan, Zhang Xiangwei, Yang Renfeng, Sun Zhiming
School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China.
Nanomaterials (Basel). 2022 Aug 17;12(16):2827. doi: 10.3390/nano12162827.
The development of economically applicable, highly efficient and low cost photocatalytic materials has always been a challenge. In this work, we report a zirconium doped TiO2/diatomite (ZrTD) composite with enhanced visible light-induced photocatalytic activity. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, UV-VIS diffused reflectance spectroscopy, high-performance liquid chromatography-mass spectrometry, photoluminescence and X-ray photoelectron spectroscopy, respectively. The optimal doping ratio of zirconium into TiO2 was obtained at 3% (3%ZrTD composite), and the degradation rate constant of which tetracycline (TC) is up to around 8.65 times higher that of zirconium doped TiO2. In addition, zirconium doping introduces the impurity levels of Zr 3d and oxygen vacancies into the lattice of TiO2, resulting in broadening the light absorption range, reducing the band gap, and improving the separation efficiency of photogenerated electron-hole pairs, thus endowing with visible light photocatalytic properties. Moreover, both the photogenerated holes (h+) and superoxide (•O2-) radicals are responsible for the degradation process of TC, and a possible degradation pathway and the corresponding intermediate products of TC by ZrTD composite are also proposed in detail.
开发经济适用、高效且低成本的光催化材料一直是一项挑战。在本工作中，我们报道了一种具有增强的可见光诱导光催化活性的锆掺杂二氧化钛/硅藻土（ZrTD）复合材料。所制备的样品分别通过X射线衍射、扫描电子显微镜、紫外-可见漫反射光谱、高效液相色谱-质谱、光致发光和X射线光电子能谱进行表征。锆在二氧化钛中的最佳掺杂比例为3%（3%ZrTD复合材料），其对四环素（TC）的降解速率常数比锆掺杂二氧化钛高出约8.65倍。此外，锆掺杂将Zr 3d杂质能级和氧空位引入到二氧化钛晶格中，导致光吸收范围拓宽、带隙减小以及光生电子-空穴对的分离效率提高，从而赋予其可见光光催化性能。此外，光生空穴（h+）和超氧自由基（•O2-）均对TC的降解过程起作用，并且还详细提出了ZrTD复合材料对TC的可能降解途径及相应的中间产物。
