摘要
通过溶胶-凝胶法联合水热合成法制备了氮掺杂TiO_2纳米管,并以该纳米管为载体,采用绿色无毒的赖氨酸作为链接剂和螯合剂,一步实现金粒子在TiO_2纳米管上的高度分散,制备得到高分散金粒子修饰氮掺杂TiO_2纳米管催化剂(Au/N-TiO_2纳米管).表征了产物的形貌、结构、光学特性及组成,通过紫外光下甲基橙水溶液的光降解率评价产物的光催化活性,讨论了氮掺杂量、金负载量、赖氨酸及焙烧对合成催化剂光催化性能的影响.结果显示,在赖氨酸存在下,金粒子在TiO_2纳米管上呈高度分散状态,未发生聚集.且与纯TiO_2纳米管相比,Au/N-TiO_2纳米管显示出更高的光催化活性.Au/N-TiO_2纳米管的高催化活性是由于氮掺杂后引起的TiO_2带隙能窄化、金粒子在载体上的高分散状态及金与TiO_2形成的肖特恩势垒引起的低电子-空穴复合率共同作用导致的.
N-doped TiO2 nanotubes were synthesized by the combination of sol-gel and hydrothermal methods firstly; and then Au nanoparticles were deposited on the N-doped TiO2 nanotubes by a simple one-pot process with lysine as both the linker and capping agent. The morphology,structure,optical absorption and composition of the samples were characterized by means of TEM,XRD,UV-Vis and XPS. The photodegradation rates of methyl orange under UV light irradiation were used to evaluate the photocatalytic activities of samples. The effects of N content,Au content,lysine and calcination on the photocatalytic activities of Au / N-doped TiO2 nanotubes were discussed. The results exhibit that Au nanoparticles capped by lysine are highly dispersed on the support without any aggregation and the obtained sample exhibits higher photocatalytic activity in comparison with pure TiO2 nanotubes. The improved photocatalytic activity is attributed to the narrower band gap of N-doped TiO2,the high dispersion of Au nanoparticles and the reduced recombination of photogenerated electrons and holes caused by the formation of metal-semiconductor Schottky junction between Au and TiO2.
作者
安会琴
于育才
闫琳
吴婷婷
李晓峰
贺晓凌
赵莉芝
黄唯平
AN Huiqin YU Yucai YAN Lin WU Tingting LI Xiaofeng HE Xiaoling ZHAO Lizhi HUANG Weiping(School of Environmental and Chemical Engineering, State Key Laboratory of Separation Membranes and Membrane Processes, Tianjin Polytechnic University, Tianjin 300387, China School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, China Key Laboratory of Advanced Energy Materials Chemistry, Ministry of Enducation, Nankai University, Tianjin 300071, China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2016年第11期2034-2042,共9页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21501131
21373120)
天津工业大学国家级大学生创新创业训练计划项目(批准号:201510058021)
天津市科技特派员项目(批准号:15JCTPJC57500)资助~~
关键词
二氧化钛纳米管
氮掺杂
金粒子
赖氨酸
光降解甲基橙
TiO2 nanotube
N doping
Au nanoparticle
Lysine
Photodegradation of methyl orange
