A series of efficient adsorbents for CO 2 capture was prepared by a wet-impregnation method. Mesostructured cellular silica foam (MF) was selected as a support and modified with a mixture of tetraethylenepentamine (TEPA) and imidazoles (Ims) to improve the initial and working CO 2 -adsorption capacity. The heat of adsorption was also evaluated. The impact of different amines and the adsorption temperature on CO 2 -adsorption performance was investigated. Some Ims showed a synergistic effect with TEPA regarding adsorption/desorption performance. Impregnating MF with such Ims and TEPA increased CO 2adsorption performance and decreased the heat of absorption compared with those obtained for MF impregnated only with TEPA. MF modified with 30 wt % 4-methylimidazole and 40 wt % TEPA exhibited a high first-pass CO 2 adsorption capacity of 4.88 mmol/g at 100 kPa and 40 °C. Following vacuum regeneration, a working capacity of 4.15 mmol/g was observed for the same conditions.