Mesoporous SiO2 yolk shell confined core-satellite Ag nanoparticles: Preparation and catalytic activity

In this work, novel mesoporous SiO2 yolk-shell confined core-satellite Ag nanoparticles (Ag@mSiO(2)) synthesized with a simple route were reported. Firstly, the core/shell Ag@C nanospheres whose carbon shells were doped with Ag nanoparticles, were facilely prepared by using a simple hydrothermal method. After coating with a uniform layer of hybrid SiO2 in the presence of octadecyltrimethoxysilane (C18TMS), the Ag@C@h-SiO2 composite nanospheres were obtained. The final calcination removed all the carbon and organic compound and left the yolk shell Ag@mSiO(2) nanosphere, in which an individually large Ag core and many tiny Ag nanoparticles were encapsulated within the mesoporous silica shell. The coresatellite like Ag nanoparticles exhibited excellent catalytic activity in RhB reduction. Benefited from the m-SiO2 shell with a uniform pore size of 3.5 nm, the bi-mode Ag nanoparticles were very stable, thus the activity of Ag@mSiO(2) could keep as high as 92% after five cycles. (C) 2016 Elsevier B.V. All rights reserved.