In this work we have examined the H2 evolution ability of carbon dots and nitrogen dopped materials, in the presence of cobalt catalysts in aqueous media. The key substance for the efficient H2 production was the presence of TCEP/Asc as sacrificial electron donor material. TCEP is well known to prevent the formation of dehydroascorbic acid that prevents the ability of ascorbic acid to give electrons to the photosensitizer. The study demonstrated that cobaloxime and porphyrin based cobalt catalysts are not able to promote the photocatalysis. Whereas the quite stable cyclic catalyst CatCo(III)1 was capable to produce a record high H2 production of 17.1 μmol (TONCAT = 859) under UV led radiation. The photocatalytic H2 production of our system is performed via a reductive quenching by the SED whereas two electrons are needed to be transferred to the protons for H2 production. This system offers a great potential for future work, to explore more water-soluble catalysts and even extent the doping onto the carbon dots with noble-free elements in order to improve the light absorption ability. The only drawback of this system is the use of a SED. The improved photocatalytic system can be even applied into the real world since the sun is able to produce H2 and by just adding low-cost carbon dots onto the system it can operate for several weeks.

Carbon dots for photocatalytic H2 production in aqueous media with molecular Co catalysts

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.