Visible-Light-Driven Hydrogen Evolution Using Planarized Conjugated Polymer Photocatalysts

Linear poly(p-phenylene)s are modestly active UV photocatalysts for hydrogen production in the presence of a sacrificial electron donor. Introduction of planarized fluorene, carbazole, dibenzo[b,d]thiophene or dibenzo[b, d]thiophene sulfone units greatly enhances the H-2 evolution rate. The most active dibenzo[b, d] thiophene sulfone copolymer has a UV photocatalytic activity that rivals TiO2, but is much more active under visible light. The dibenzo[b, d]thiophene sulfone co-polymer has an apparent quantum yield of 2.3% at 420 nm, as compared to 0.1% for platinized commercial pristine carbon nitride.