Ag_(2)O/WO_(3)-SiO_(2)气凝胶的制备及光催化性能研究  

Preparation and photocatalytic properties of Ag_(2)O/WO_(3)-SiO_(2) aerogels

作　　者：陈宝宁 丁春华 方岩雄[1] 刘全兵[1] CHEN Baoning;DING Chunhua;FANG Yanxiong;LIU Quanbing(School of Light Industry and Chemical Engineering,Guangdong University of Technology,Guangzhou 510006,China;State Key Laboratory of Marine Resources Utilization in the South China Sea,Hainan University,Haikou 570228,China;Hainan Special Glass Laboratory,Haikou 570228,China)

机构地区：[1]广东工业大学轻工化工学院,广东广州510006 [2]海南大学南海海洋资源利用国家重点实验室,海南海口570228 [3]海南省特种玻璃实验室,海南海口570228

出　　处：《工业水处理》2023年第2期136-141,共6页Industrial Water Treatment

摘　　要：为扩大WO_(3)-SiO_(2)气凝胶的可见光吸收范围,改善其光催化效果,先以溶胶-凝胶法制备了WO_(3)-SiO_(2)气凝胶,再采用浸渍法制备了不同Ag_(2)O负载量的Ag_(2)O/WO_(3)-SiO_(2)复合气凝胶光催化剂。通过扫描电镜(SEM)、X射线衍射分析仪(XRD)、X射线光电子能谱仪(XPS)、紫外-可见光谱仪(UV-vis)、荧光分光光度计(PL)对样品进行了表征分析,并在464 nm波长光源下考察了样品光催化降解亚甲基蓝(MB)的性能。表征结果表明,负载的Ag_(2)O与WO_(3)-SiO_(2)气凝胶中的WO3存在电子转移相互作用,形成了Ag_(2)O/WO3异质结;Ag_(2)O/WO3异质结使催化剂的带隙宽度变窄,有利于光生电子-空穴的激发,同时抑制了电子-空穴对的复合。结合光催化剂降解MB的效果,负载Ag_(2)O形成的Ag_(2)O/WO3异质结增强了Ag_(2)O/WO_(3)-SiO_(2)气凝胶的可见光吸收能力,提高了其光催化性能。其中,Ag_(2)O负载量为0.4%(质量分数)的Ag_(2)O/WO_(3)-SiO_(2)气凝胶具有最佳的催化降解性能,2 h内对MB的降解率达到94.91%,较WO3/SiO2气凝胶提高了58.17%。根据催化剂的能带结构分析,推断了Ag_(2)O/WO3异质结降解MB的可能机理为Ⅱ型异质结机理。In order to expand the visible light absorption range of WO_(3)-SiO_(2)aerogel and improve its photocatalytic effect,WO_(3)-SiO_(2)aerogel was fabricated by sol-gel method firstly,and then Ag_(2)O/WO_(3)-SiO_(2)composite aerogel photo⁃catalysts with different Ag_(2)O loadings were synthesized through impregnation route.The composites were character⁃ized by scanning electron microscopy(SEM),X-ray diffraction analysis(XRD),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible spectroscopy(UV-vis),and fluorescence spectrophotometer(PL).The photocatalytic deg⁃radation of methylene blue(MB)by the composite samples were investigated under the light source of 464 nm wave⁃length.The characterization analyses showed that the loaded Ag_(2)O could interact with WO3 in the WO_(3)-SiO_(2)aerogel by electron transfer,and the Ag_(2)O/WO3 heterojunction was formed.The heterojunction narrowed the band gap width of the catalyst,which was beneficial to the excitation of photogenerated electrons and holes,while suppressing the re⁃combination of electron-hole pairs.Based on the results of the photocatalytic degradation of MB,the Ag_(2)O/WO3 het⁃erostructure formed by loading Ag_(2)O enhanced the visible light absorption ability and improved the photocatalytic performance.The MB degradation rate of 0.4%Ag_(2)O/WO_(3)-SiO_(2)aerogel reached 94.91%within 2 h,which was 58.17%higher than that of unmodified WO_(3)-SiO_(2)aerogel.According to the band structure analysis of the catalyst,the possible mechanism of MB degradation by Ag_(2)O/WO3 aerogel was proposed asⅡ-scheme heterostructure.

关 键 词：氧化钨 光催化 气凝胶 氧化银 亚甲基蓝 异质结 

分 类 号：X703[环境科学与工程—环境工程]