Functionalization of the surface support (silica gel, MCM-41 and SBA-15) was achieved by grafting organic aminosilanes by direct condensation and hydrolysis methods. The amine modified silicates can chemically bind to acidic CO₂ molecules at low temperatures, and thus are potentially good candidates for CO₂ capturing. To increase the adsorptive capabilities for these materials, the surface was tailored using two suitable amine silane linkers, (3-aminopropyl)trimethoxysilane (APTS) and N-[3-(trimethoxysilyl)propyl]-ethylenediamine (TEPD). The resulted adsorbents were characterized, by physical, elemental analysis, and spectroscopic techniques. The adsorption capacity of modified adsorbents was significantly increased after grafting, clearly indicates the affirmative impact of amines for CO₂ adsorption.