Conjugated donor-acceptor polymer photocatalysts with electron-output "tentacles" for efficient hydrogen evolution

The tunable structures and versatile properties for conjugated polymers (CPs) make them viable as a molecular platform for photocatalytic water splitting. Normally, structure design of polymer photocatalyst is focus on tuning its optical band structure or charge-separation ability, the importance of electron-output ability in photocatalytic process is always ignored. This study demonstrates a molecular engineering strategy by introducing an electron-output "tentacle" site, i.e. dibenzothiophene-S,S-dioxide (FSO) unit, into the polymer backbone to construct a series of donor-acceptor type conjugated polymer photocatalysts for efficient hydrogen evolution, which not only results in optimized light absorption ability and excellent exciton-separation, but also leads to the efficient electron-output ability. Detailed DFT calculations further theoretically confirm the vital role of FSO unit as an electron-output "tentacle" site.