A one-pot hydrothermal synthesis was used to obtain a mesoporous SiO2-graphene hybrid from tetraethylortho silicate and graphene oxide without any surfactant. Graphene obtained from hydrothermal reduction, with a certain oxygen-containing groups, plays a key role in attaching SiO2 nanoparticles, as examined by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy. The synthesis technique combines protection, reduction and functionalization in one step. Nitrogen adsorption/desorption isotherms showed that the hybrid was tunable in surface area (244.7-524.61 m(2)/g), pore size (8.9-69.26 nm) and its distribution by simple adjustment of the mass ratio of tetraethylortho silicate and graphene oxide. (C) 2012 Elsevier B.V. All rights reserved.