In this work, a facile route was designed to fabricate bimodal porous silica with high surface area and pore volume via a CO2-expanded gelation with assistance of CTAB. Parameters such as the amount of CTAB, pressure of CO2 and agitation time were investigated and optimized. Results showed bimodal silica contained small pore size (around 2 nm) from CTAB templating and large pore size (> 4 nm) from CO2-expanded gelation could be easily adjusted by the synthesis conditions. A typical sample with surface area of 1133 m(2)/g and pore volume of 1.24 mL/g was applied as a catalyst support for phosphotungstic acid, revealing much faster catalysis rate and relatively high selectivity for 1, 8-cineole from alpha-terpineol than the commercial MCM-41. The approach was also successfully extended to the preparation of bimodal NiO/silica composite, and the reduced Ni/silica showed higher catalysis performance than the unimodal sample for phenol hydrogenation to cyclohexanol.