单层组装纳米金表面结构变化与催化性能调控  

The surface structural changes of self-assembly monolayer Au nanoparticles and their regulated catalytic activity

作　　者：王明月[1,2] 牛瑞[1,2] 黄敏[1,2] 张颖[1,2] 

机构地区：[1]应用表面与胶体化学教育部重点实验室 [2]陕西师范大学化学化工学院,西安710062

出　　处：《中国科学：化学》2015年第1期76-89,共14页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(21173141);陕西省工业攻关项目(2011K08-14);"高等学校学科创新引智计划"(B14041);陕西师范大学大学生创新研究项目(cx13123)资助

摘　　要：本文以壳层为无机-有机杂化网络结构的核-壳型聚苯乙烯/二氧化硅/聚(N-异丙基丙烯酰胺共聚甲基丙烯酰氧丙基三甲氧基硅烷)(PS/Si O2/P(NIPAM-co-MPTMS))复合微球为载体,原位控制合成纳米金微粒;利用不同链长烷基硫醇在纳米金表面自组装作用,获得负载型纳米金催化剂.结果表明,以对硝基苯酚还原为模型催化反应,通过调整还原剂硼氢化钠用量,可以实现对纳米金表面结构的调整.另外,烷基硫醇链长和修饰量显著影响其催化反应活性.研究发现,Au?S键的解吸作用更易于在纳米金表面形成烷基链保护的局部反应微区,因此,烷基硫醇单层组装纳米金表面结构变化可以实现对催化性能的调控.In this paper, Au nanoparticles（Au NPs） were in-situ synthesized on the shell layer of the core-shell type polystyrene/Si O2/poly（N-isopropylacrylamide-co-3-methacryloxypropyltrimethoxysilane）（PS/Si O2/P（NIPAM-coMPTMS）） composite microspheres with inorganic-organic hybrid network structure as support. The supported Au NPs catalysts were obtained by using self-assembly of alkanethiol compound with the different chain length on the surface of Au NPs. We chose the reduction of 4-nitrophenol（4-NP） as a model reaction. The results were demonstrated that the surface structure of Au NPs can be regulated via changing the dosage of sodium borohydride reducing agent. In addition, the catalytic activity was significantly influenced by the chain length and modified amounts of the alkanethiol. The results have found that the desorption of Au-S bond is prefer to form the local reaction micro-sites comprising of alkyl chain. Therefore, the catalytic performance could be regulated by changing the surface structures of the alkanethiol self-assembly monolayer（SAMs） on the Au NPs surface.

关 键 词：纳米金 烷基硫醇 自组装单层 负载型催化剂 对硝基苯酚还原 

分 类 号：TB383.1[一般工业技术—材料科学与工程] O643.36[理学—物理化学]