化工进展 ›› 2018, Vol. 37 ›› Issue (11): 4500-4508.doi: 10.16085/j.issn.1000-6613.2018-0499

• 资源与环境化工 • 上一篇    下一篇

水热合成Ag+掺杂SrTiO3可见光催化降解四环素性能和机制

曹丽丽, 蒋善庆, 凌泽玉, 汪楚乔, 许霞, 王利平   

  1. 常州大学环境与安全工程学院, 江苏 常州 213164
  • 收稿日期:2018-03-12 修回日期:2018-05-24 出版日期:2018-11-05 发布日期:2018-11-05
  • 通讯作者: 王利平,教授,硕士生导师,研究方向为水资源及饮用水安全保障技术。E-mail:wlp@cczu.edu.cn。
  • 作者简介:曹丽丽(1993-),女,硕士研究生,研究方向为环境功能材料制备及难降解有机物处理。
  • 基金资助:
    国家自然科学基金(21477050,21607017)及常州国际科技合作计划(CZ20140017)项目。

Properties and mechanisms of tetracycline photocatalytic degradation by hydrothermal synthesis Ag-SrTiO3 in visible-light

CAO Lili, JIANG Shanqing, LING Zeyu, WANG Chuqiao, XU Xia, WANG Liping   

  1. School of Environmental & Safety Engineering, Changzhou University, Changzhou 213164, Jiangsu, China
  • Received:2018-03-12 Revised:2018-05-24 Online:2018-11-05 Published:2018-11-05

摘要: 采用一步水热法制备纳米Ag-SrTiO3可见光催化剂,利用X射线衍射、X射线光电子能谱、扫描电镜和紫外可见光吸收光谱等对Ag-SrTiO3的组成、形貌及吸光性进行表征,通过对四环素(TC)的降解实验研究了其在可见光下的光催化活性和稳定性,并进一步通过光致发光光谱、电子自旋共振和自由基捕获实验探究了其对TC的降解机制。结果表明,Ag+可成功掺杂到SrTiO3中,且Ag-SrTiO3的吸收光较纯SrTiO3明显发生红移;当AgNO3与Sr(NO32的摩尔分数为3%时,制备的Ag-SrTiO3对TC的光降解效果最好,120min内降解率可达79.63%,较纯SrTiO3提高13倍,光催化降解TC反应过程符合准一级动力学模型,且重复使用8次后仍具有较高光催化活性;Ag-SrTiO3中Ag+捕获了SrTiO3产生的电子,有效抑制了电子和空穴的复合概率,从而增加其光催化活性,且其主要活性物种为·O2

关键词: 银-钛酸锶(Ag-SrTiO3), 纳米材料, 电子自旋共振, 可见光催化, 四环素

Abstract: Nano-Ag-SrTiO3 visible-light catalyst was prepared by one-step hydrothermal method. Composition, morphology and structure, visible-light absorption performance of Ag-SrTiO3 were characterized by X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), and ultraviolet visible absorption spectra(UV-vis), respectively. Photocatalytic property and stability of Ag-SrTiO3 in visible-light were studied by tetracycline(TC) degradation experiment, and its degradation mechanism for TC was also investigated by photoluminescence spectra(PL), electron spin resonance(ESR) analysis and free radical capture experiment. The results showed that Ag+ could be well doped in SrTiO3, and the absorption spectra of Ag-SrTiO3 significantly redshifted compared with pure SrTiO3. The photocatalytic property of Ag-SrTiO3 for TC degradation was optimal while the molar ratio of AgNO3 and Sr(NO3)2 was 3%, and its degradation rate could reach 79.63% within 120min, 13 times higher than pure SrTiO3. Furthermore, TC degradation of Ag-SrTiO3 showed a good compliance with the pseudo-first-order kinetic model. Ag-SrTiO3 still had excellent photocatalytic degradation activity after 8 times reuse. Electronics generated in SrTiO3 was captured by Ag+ in Ag-SrTiO3. The compound probability of electron and hole could be effectively restrained, which resulted in the increase of photocatalytic properties. The main active species of Ag-SrTiO3 was·O2-.

Key words: silver-strontium titanate (Ag-SrTiO3), nanomaterials, electron spin resonance, visible-light photocatalytic, tetracycline

中图分类号: 

  • X703