Adsorption characteristics of nanoporous carbon-silica composites synthesized from graphite oxide by a mechanochemical intercalation method

Nanoporous carbon-silica composites were synthesized from graphite oxide (GO) precursor by a mechanochemical intercalation (MCI) method at different conditions, and their structural property, thermal decomposition behaviors, and adsorption characteristics were examined. MCI method yields regular tetraethoxysilane (TEOS)-intercalated GO layer structures with controllable silicon content depending on the TEOS addition. Adsorption behaviors of water and hexane indicate the amphiphilic properties of the composites. The detailed porosities of the composites and their changes upon water adsorption were analyzed on the basis of alpha(s)-plot method of N-2 adsorption isotherms using a weight-averaged standard data from non-porous silica and non-porous carbon, which plausibly divides microporosity and mesoporosity. (c) 2007 Elsevier Inc. All rights reserved.