摘要
采用密度泛函理论,在分子水平上研究了负载金团簇对金红石型二氧化钛光催化性能的影响及机理。优化得到了6种金团簇(n=2-7)稳定结构,并分别吸附于金红石型二氧化钛(110)面形成稳定吸附体系。研究表明,Aun团簇与TiO2(110)面上的氧原子形成共价键,属于化学吸附,Au-O键长是影响体系稳定性的主要因素,奇数Aun团簇吸附稳定性优于偶数的,出现奇偶振荡现象;Aun团簇使TiO2能带发生裂分,在禁带中增加多个能级,随着Aun团簇的增大,TiO2禁带宽度明显变窄,吸收光进入可见光区,增强了二氧化钛的光催化性能。
Using first-principles methods based on density functional theory(DFT),the effect and mechanism of supported gold clusters on the photocatalytic properties of rutile titanium dioxide are studied at molecular level.Six gold clusters(n=2-7)were optimized and adsorbed on the surface of TiO2(110)to obtain six stable adsorption systems.The results show that the covalent bond formed between the Au cluster and the oxygen atom on the surface of TiO2(110)presenting chemisorption,and the Au-O bond length was the decisive factor affecting the stability of the systems.The adsorption of odd-numbered Aun clusters is more stable than that of even-numbered clusters.Through energy band analysis,it is found that the Aun clusters make the TiO2 band splitting,and increase multiple energy levels in the band gap.With the increase of the Au clusters,the band gap width of TiO2 becomes narrower obviously,the wavelength of absorption light enters the visible region,so the photocatalytic performance can be enhanced.
作者
夏树伟
杨继宏
于良民
XIA Shu-Wei;YANG Ji-Hong;YU Liang-Min(The Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education,College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第10期55-61,共7页
Periodical of Ocean University of China
基金
青岛海洋科学与技术试点国家实验室鳌山人才培养项目(2017ASTCP-OS02)资助。
关键词
金团簇
二氧化钛
密度泛函
能带结构
化学吸附
gold clusters
titanium dioxide
density functional theory
band structure
chemisorption
