Materials Research Bulletin, Vol.47, No.9, 2396-2402, 2012
Preparation of magnetically recoverable Fe3O4@SiO2@meso-TiO2 nanocomposites with enhanced photocatalytic ability
A simple and efficient method has been developed to fabricate core-shell structured Fe3O4@SiO2@meso-TiO2 nanocomposites with enhanced photocatalytic activity in this paper. The as-made core-shell structure is composed of a central magnetite core with a strong response to external fields, an interlayer of SiO2, and an outer layer of TiO2 nanocrystals with mesoporous structure. Fe3O4@SiO2 was obtained through a sol-gel process. To avoid magnetic loss caused by magnetite core phase transition and particle reunion, we adopt a mild synthetic method to get anatase shell instead of traditional high-temperature calcination. The structure of resulting composites was characterized and their photocatalytic activities were also tested. Fe3O4@SiO2@meso-TiO2 composite exhibits higher photocatalytic activities than Fe3O4@SiO2@solid-TiO2 for the degradation of rhodamine B in aqueous suspension. The excellent photocatalytic activities are ascribed to the high surface area and pore volume created by mesoporous anatase shell. (C) 2012 Elsevier Ltd. All rights reserved.