三角形Au@TiO2介孔催化剂可见光降解亚甲蓝
Visible light degradation of methylene blue from water by triangle Au@TiO2 mesoporous catalyst
刘兵 1张黄 2韩洪亮 3胡长文 4张英磊1
作者信息
- 1. 北京首创生态环保集团股份有限公司,北京 100037;北京首创北科环境科技研究院有限公司,北京 100044
- 2. 北京工业大学环境与能源工程学院,北京 100124
- 3. 首都师范大学化学系,北京 100089
- 4. 北京理工大学化学与化工学院,北京 102401
- 折叠
摘要
利用溶胶凝胶法制备出一种三角形Au@TiO2核壳材料.经过水热晶化,该材料膨胀至300nm,壳层TiO2晶化为介孔锐钛矿相,但核心三角形Au颗粒的形貌保持不变.采用粉末X射线衍射(PXRD)、ξ电位、高分辨透射电子显微镜(HRTEM)、热重分析(TGA)、光致发光(PL)光谱、光电流(i-t)以及光催化降解技术,对样品的结构和性能进行了系统、详细的检测与分析.经过晶化处理的Au@TiO2在可见光波段的光降解亚甲蓝性能比未晶化时有了显著的提升,1 mg·mL-1 Au@c-TiO2可以在可见光照射1 h后实现对60 mg·L-1亚甲蓝全降解.电子顺磁共振(EPR)测试表明·O2-和·OH两种自由基对光降解起到了很大作用.通过综合分析实验结果和时域有限差分(FDTD)分析,探究了催化反应的机理.
Abstract
TiO2-coated triangle Au with a core-shell structure(Au@TiO2)was synthesized using the sol-gel method.After hydrothermal crystallization,the particle size expanded to 300 nm with crystallization of the shell TiO2 into a mesoporous anatase phase,while the morphology of the triangle Au particle remained unchanged.The structure and properties of the samples were characterized using powder X-ray diffraction(PXRD),ξ potential,high-resolution transmission electron microscopy(HRTEM),thermogravimetric analysis(TGA),photoluminescence(PL)spectrosco-py,photocurrent(i-t)measurements,and methylene blue(MB)photodegradation tests.The results revealed that the photocatalytic degradation rate of crystallized triangle Au@TiO2 was significantly higher than that of the amorphous material.Specifically,1 mg·mL-1 Au@c-TiO2 achieved complete degradation of 60 mg·L-1 MB after one hour of visi-ble light irradiation.An electron paramagnetic resonance(EPR)experiment was conducted,indicating that·O2-and ·OH are the active species responsible for the degradation process.By combining experimental results with finite-difference time-domain(FDTD)analysis,we proposed a mechanism for the photodegradation process.
关键词
光降解/二氧化钛/三角形金颗粒/可见光Key words
photodegradation/TiO2/triangle Au particle/visible light引用本文复制引用
基金项目
国家自然科学基金(21671019)
国家自然科学基金(21231002)
国家自然科学基金(21471016)
111项目(B07012)
973项目(2014CB932103)
出版年
2024
NETL
NSTL
万方数据