(582as) Direct Phtocatalytic Reduction of Bicarbonate to Formate on Plasmonic Metallic Nanoparticles

A remarkably enhanced yield of formic acid (~270 mM formic acid/g cat-hr) is observed by photoreduction of bicarbonate under solar light using ~15 nm gold nanoparticles in the presence of glycerol as a hole scavenger. Interestingly, the productivity of formic acid using gold nanoparticle catalysts was found to be even higher than conventional TiO₂ nanocatalysts. In addition, we studied the Au nanoparticle catalyzed photoreduction of resazurin in parallel. For both of the photoreduction reactions 15 nm gold nanoparticles were more efficient than 50 nm Ag nanoparticles. The enhanced efficiency of gold nanoparticle is attributed to their higher light absorption efficiency.