Selective photoelectrocatalytic tuning of benzyl alcohol to benzaldehyde for enhanced hydrogen production

Hydrogen production can be promoted by replacing sluggish oxygen evolution reaction (OER) with a thermodynamically more favorable reaction, the primary oxidation reaction of benzyl alcohol to benzaldehyde. On a Bi2MoO6@TiO2NTA photocathode, the conversion of benzyl alcohol to benzaldehyde is realized with the selectivity of 100 %. This is originated from enhanced adsorption and activation of benzyl alcohol on this photoanode, as confirmed from tested by in situ FTIR techniques. The electrons generated during such a controllable and selective primary oxidation reaction is then utilized as the source for synergistical hydrogen production. The amount of generated hydrogen is then 5.5 times higher than that when OER is used. The efficiency for such hydrogen production is as high as 85 %. The proposed strategy combines solar energy and biomass for the efficient production of the valuable raw material - benzaldehyde as well as green energy source - hydrogen.