Dual Ag/Co cocatalyst synergism for the highly effective photocatalytic conversion of CO(2) by H(2)O over Al-SrTiO(3)

Loading Ag and Co dual cocatalysts on Al-doped SrTiO(3) (AgCo/Al-SrTiO(3)) led to a significantly improved CO-formation rate and extremely high selectivity toward CO evolution (99.8%) using H(2)O as an electron donor when irradiated with light at wavelengths above 300 nm. Furthermore, the CO-formation rate over AgCo/Al-SrTiO(3) (52.7 μmol h(−1)) was a dozen times higher than that over Ag/Al-SrTiO(3) (4.7 μmol h(−1)). The apparent quantum efficiency for CO evolution over AgCo/Al-SrTiO(3) was about 0.03% when photoirradiated at a wavelength at 365 nm, with a CO-evolution selectivity of 98.6% (7.4 μmol h(−1)). The Ag and Co cocatalysts were found to function as reduction and oxidation sites for promoting the generation of CO and O(2), respectively, on the Al-SrTiO(3) surface.