Highly Efficient Photocatalytic System Constructed From Spherical SBA-15-Cobalt Compounds and Ru (II) Complex for Visible-Light Driven Co 2 Reduction
SBA-15, a type of ordered hexagonal array mesoporous silica with two-dimensional hexagonal structure, a large ratio of specific surface area to pore volume, and 5 ~ 30 nm pore diameter, has received much attention because of its favorable catalytic activities for adsorption, separation and transformation of bulkier molecules. In this research, cobalt oxide nanoparticles were immobilized on the surfaces of spherical mesoporous silicate particles to synthesize spherical CoO-s-SBA-15 and Co3O4-s-SBA-15, their morphologies and structures have been characterized by XRD, SEM, TEM, XPS, BJH and BET analysis. The hybrid catalysts had a pore diameter of ~5.7 nm, surface area of ~440 m2 g–1, and sphere diameter of 2–8 µm, and exhibited high visible-light-driven catalytic performance in converting CO2 to CO in aqueous solutions containing a Ru-based photosensitizer under ambient conditions. Average generation rates of CO of up to 25,626 and 11,420 µmol h–1 g–1 were achieved in the first 2.5 h of reaction for catalysts with CoO and Co3O4, respectively, and a high CO selectivity of 85.1% was observed for the former in the CO2 photoreduction system. The results showed that these hybrid catalysts are advantageous for CO2-to-CO conversion because of their large surface area, favorable CO2 absorption properties, and surface hydroxyl groups that can interact with CO2 strongly.
"Highly Efficient Photocatalytic System Constructed From Spherical SBA-15-Cobalt Compounds and Ru (II) Complex for Visible-Light Driven Co 2 Reduction"
ETD Collection for Tennessee State University.