Synthesis of nanoporous graphite-derived carbon/TiO2-SiO2 composites by a mechanochemical intercalation method

Nanoporous composites of carbon nanosheets and single or mixed TiO2 and SiO2 were synthesized from graphite oxide (GO) precursor by a mechanochemical intercalation (MCI) method and their structural and adsorption/photocatalytic properties examined. It was found that a mixed Ti and Si organic phase behaves differently from a single phase in the MCI process, with linkages of SiO2 and TiO2 forming between the carbon layers, leading to an intercalation structure with improved surface hydrophilicity and a composite with enhanced microporosity and a reduced total amount of oxides. Although structural regularity of intercalated GO becomes poorer by applying Ti species in the MCI method, carbon-mixed oxide composites with an appropriate pore structure and sufficient Ti content exhibit a synergy effect of adsorption concentration and photocatalysis toward organic molecules. (C) 2008 Elsevier Inc. All rights reserved.