催化学报

催化学报 ›› 2019, Vol. 40 ›› Issue (8): 1212-1221.DOI: 10.1016/S1872-2067(19)63359-0

• 论文 • 上一篇    下一篇

SiO2修饰强化BiOCl纳米片对有机污染物的光催化降解性能

余长林a, 何洪波b,c, 刘兴强d, 曾巨澜e, 刘珍a   

  1. a 广东石油化工学院环境科学与工程学院, 广东省石油化工污染过程与控制重点实验室, 广东茂名 525000;
    b 中山大学材料科学与工程学院, 广东广州 510275;
    c 中山大学化学工程与技术学院, 广东珠海 519082;
    d 厦门大学嘉庚学院环境科学与工程学院, 河口生态安全与环境健康重点实验室, 福建漳州 363105;
    e 长沙理工大学化学与食品工程学院, 湖南长沙 410114
  • 收稿日期:2019-01-23 修回日期:2019-03-20 出版日期:2019-08-18 发布日期:2019-06-21
  • 通讯作者: 余长林, 刘兴强
  • 基金资助:
    国家自然科学基金（21567008，21707055）；广东石油化工学院创新团队发展计划资助计划，广东省扬帆人才计划；江西省5511科技创新人才计划（20165BCB18014）；江西省主要学科学术和技术带头人资助计划（20172BCB22018）；福建省高校新世纪优秀人才支持计划；湖南省自然科学基金杰出青年基金（2017JJ1026）.

Novel SiO2 nanoparticle-decorated BiOCl nanosheets exhibiting high photocatalytic performances for the removal of organic pollutants

Changlin Yua, Hongbo Heb,c, Xingqiang Liud, Julan Zenge, Zhen Liua   

  1. a School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control, Guangdong University of Petrochemical Technology, Maoming 525000, Guangdong, China;
    b School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, China;
    c School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, Guangdong, China;
    d School of Environmental Science and Engineering, Key Laboratory of Estuarine Ecological Security and Environmental Health, Xiamen University Tan Kah Kee College, Zhangzhou 363105, Fujian, China;
    e School of Chemisry and Food Engineering, Changsha University of Science and Technology, Changsha 410114, China
  • Received:2019-01-23 Revised:2019-03-20 Online:2019-08-18 Published:2019-06-21
  • Supported by:
    We acknowledged the funding from the National Natural Science Foundation of China (21567008, 21707055), the Program for Innovative Research Team of Guangdong University of Petrochemical Technology, the Yangfan talents Project of Guangdong Province, the Innovation-driven "5511" Program in Jiangxi Province (20165BCB18014), the Funding Program for Academic and Technological Leaders of Major Disciplines in Jiangxi Province (20172BCB22018), the Program for New Century Excellent Talents in Fujian Province University, and the Natural Science Foundation for Distinguished Young Scholars of Hunan Province, China (2017JJ1026).

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摘要： 许多有机污染即使在很低浓度下也可对水生生物造成各种不利影响.例如，作为合成环氧树脂和聚碳酸酯重要原料的双酚A是一种典型的内分泌干扰化学物质，当大量的双酚A被排放到水环境中时，必将对水生生态环境造成不可修复的破环.光催化技术具有催化效率高、矿化能力强和环境友好等优点，是很有应用前景的有机污染物降解方法.但是，目前大多数光催化剂尚难以满足实际有机废水处理或其它环境净化的需求.限制光催化剂大规模应用的原因可归结于以下两方面：一是光催化反应中的量子效率较低，大部分光生电子和空穴被复合而消耗掉，这使得电子和空穴很难迁移到催化剂表面及与吸附的目标降解物发生氧化反应；二是太阳光利用效率较低，在光催化剂体系中，宽带隙的半导体占有很大比重，而宽带隙的光催化剂需要短波长的紫外光来激发电子跃迁，这极大限制了自然太阳光或人工可见光的使用.
BiOCl是一种绿色、稳定的新型光催化剂，具有材料易得、制备方法简单和形貌可控等诸多优点.为了进一步提高BiOCl光催化剂对有机污染物的降解活性，本文从提高量子效率的角度出发，采用SiO2纳米粒子修饰BiOCl纳米片光催化剂，以期提高光生电子和空穴分离效率，进而增强BiOCl纳米片对有机污染物的光催化降解活性.我们首先采用水解法制备了SiO2纳米粒子，然后通过水热反应制备了SiO2纳米粒子修饰的BiOCl复合光催化剂.利用XRD，FT-IR，SEM/TEM，BET，UV-vis DRS，XPS和光电流等表征手段分析了样品的物理化学性质.催化活性测试表明，SiO2/BiOCl在苯酚、双酚A和罗丹明B等有机污染物的光催化降解中表现出优越的光催化活性和稳定性.与单纯的BiOCl相比，1.88% SiO2/BiOCl样品对罗丹明B、双酚A和苯酚的降解率分别提高了16.5%，29.0%和38.7%.
SiO2纳米粒子修饰使催化性能提升的主要原因如下：首先，SiO2的修饰增加了复合材料的比表面积，增强了污染物的吸附能力，为污染物降解提供了更多的活性位点；其次，适当的SiO2耦合有利于（110）晶面生长，高暴露的特殊晶面为电子迁移提供了更加高速的通道，从而提高了电子和空穴的分离效率；最后，光生电子可以通过紧密接触的SiO2/BiOCl界面转移到SiO2表面，SiO2表面的缺陷和空位能有效捕获光生电子，从而减小了光生载流子的复合几率，使更多的光生电子和空穴参与到光催化降解反应，进而提高了SiO2/BiOCl复合材料的光催化活性.

关键词: SiO2/BiOCl, 纳米片, 有机污染物, 光催化, 界面

Abstract: Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized by various techniques such as XRD, FT-IR, SEM/TEM, BET, UV-vis, DRS, XPS, and photocurrent measurements. The SiO2/BiOCl composite nanosheets displayed high photocatalytic activity and excellent stability in the degradation of organic pollutants such as phenol, bisphenol A (BPA), and rhodamine B (RhB). With respect to those over bare BiOCl, the degradation rates of RhB, BPA, and phenol over 1.88% SiO2/BiOCl increased 16.5%, 29.0%, and 38.7%, respectively. Radical capturing results suggested that h+ is the major reactive species and that hydroxyl (·OH) and superoxide (·O2-) radicals could also be involved in the degradation of organic pollutants. The enhanced photocatalytic performances of SiO2/BiOCl composites can be mainly attributed to the improved texture and the formation of intimate SiO2/BiOCl interfaces, which largely promoted the adsorption of organic pollutants, enhanced the light harvesting, and accelerated the separation of e- and h+.

Key words: SiO2/BiOCl, Nanosheets, Organic pollutant, Photocatalysis, Interface