Calcium zirconate photocatalyst and silver cocatalyst for reduction of carbon dioxide with water

Calcium and other alkaline-earth zirconate photocatalysts were prepared for photocatalytic reduction of CO2 with water in an aqueous solution. The CaZrO3 sample showed high selectivity for CO2 reduction although the BaZrO3 sample predominantly promoted water splitting. The CaZrO3 photocatalyst and other zirconate photocatalysts were compared with the corresponding alkaline-earth titanate photocatalysts to discuss their photocatalytic properties. Further, it was also found that some kinds of Ag species on the CaZrO3 sample decreased the photocatalytic activities while metallic Ag nanoparticles gave a positive effect on the photocatalytic activity for CO2 reduction.