A series of Cr-SBA-1 (Pm3n) mesoporous molecular sieves were directly synthesized under strongly acidic conditions using ammonium dichromate as chromium source and characterized by various techniques. X-ray diffraction (XRD) showed that the synthesized mesoporous materials had a well-ordered cubic structure. N-2 adsorption/desorption measurements confirmed that the resultant samples had large meso-pores (> 23 angstrom) and highly surface areas (> 1000m(2) g(-1)). FT-IR and UV-vis results revealed that both monochromate and polychromate coexisted on these mesoporous materials. All these samples prepared by direct synthesis have been used as catalysts for dehydrogenation of ethane with carbon dioxide. Among these catalysts, Cr-SBA-1(III) exhibited the highest catalytic performance, giving 21.2% of ethylene yield with a selectivity of 86.9% at 650 degrees C, whereas, its catalytic activity is lower than that of Cr-SBA-1 prepared by conventional impregnation. (c) 2006 Elsevier B.V All rights reserved.