Ordered phenyl-functionalized mesoporous hybrids with large-pore cubic Ia3d structure have been prepared in acid conditions by co-condensation of tetraethoxysilane (TEOS) and phenyltriethoxysilane (PTES) in the presence of poly (ethylene oxide)20-poly (propylene oxide)70-poly (ethylene oxide)20 (Pluronic P123). During synthesis, the amount of PTES addition plays a crucial role for the generation of special mesostructure and only in molar percentage range of 3-8% PTES with respect to total amounts of siliceous sources, can Ia3d mesoporous hybrids be obtained. Furthermore, their pore sizes can be adjusted by simply changing ageing temperature. (c) 2005 Elsevier B.V. All rights reserved.