Graft copolymer templated synthesis of mesoporous MgO/TiO2 mixed oxide nanoparticles and their CO2 adsorption capacities

Mesoporous mixed oxide nanoparticles consisting of MgO and TiO2 were synthesized via a sol–gel process by templating poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) graft copolymer. The mesoporous structures and morphologies of the MgO/TiO2 mixed oxides were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and nitrogen adsorption/desorption analysis. Interestingly, MgO/TiO2 mixed oxide exhibited much higher CO2 adsorption capacity (0.477 mol CO2/kg sorbent for 40:60 MgO/TiO2) than pure MgO (0.074) or TiO2 (0.063). This result arises from the increase in surface area and pore volume of the mixed oxide due to the formation of bimodal pores.