title: Thermal-stable carbon nanotube-supported metal nanocatalysts by mesoporous silica coating.
abstract: A universal strategy was developed for the preparation of high-temperature-stable carbon nanotube (CNT) -supported metal nanocatalysts by encapsulation with a mesoporous silica coating. Specifically, we first showed the design of one novel catalyst, Pt(@)CNT/SiO(2), with a controllable mesoporous silica coating in the range 11-39 nm containing pores ≈3 nm in diameter. The hollow porous silica shell offers a physical barrier to separate Pt nanoparticles from contact with each other, and at the same time the access of reactant species to Pt was not much affected. As a result, the catalyst showed high thermal stability against metal particle agglomeration or sintering even after being subjected to harsh treatments up to 500 °C. In addition, degradation in catalytic activity was minimized for the hydrogenation of nitrobenzene over the catalyst treated at 300 °C for 2 h. The scheme was also extended to coat porous silica onto the surfaces of CuRu(@)CNT and the resultant catalyst thereby can be reusable at least four times without loss of activity for the hydrogenolysis of glycerol. These results suggest that the as-prepared nanostructured CNT-supported catalysts may find promising applications, especially in those processes requiring rigorous conditions.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Sun
authors.forename: Hongye
authors.initials: H
authors.lastname: Zhang
authors.forename: Yanfei
authors.initials: Y
authors.lastname: Zhao
authors.forename: Changliang
authors.initials: C
authors.lastname: Huang
authors.forename: Ranting
authors.initials: R
authors.lastname: Tao
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Liu
authors.forename: Zhenduo
authors.initials: Z
authors.lastname: Wu