Tunable, light-assisted co-generation of CO and H2 from CO2 and H2O by Re(bipy-tbu)(CO)3Cl and p-Si in non-aqueous medium

The light-assisted co-generation of carbon monoxide and hydrogen from carbon dioxide and water is reported. The combination of a homogeneous CO-evolving electrocatalyst and a heterogeneous H-2-evolving photoelectrode surface provides for tunability of the H-2/CO ratio. A total Faradaic efficiency of 102 +/- 5% and a H-2/CO ratio of 2 : 1 were achieved at a low homogeneous catalyst concentration (0.5 mM) in acetonitrile/water mixtures.