Superior Photocatalytic Generation of H2in Water Medium Through Grafting a Cobalt Molecule Co‐Catalyst from Carbon Nitride Nanosheets

Abstract To develop stable, efficient, non‐noble metal‐based photocatalysts for water splitting has become a long‐standing challenge. Here, cobalt−phenanthroline active species are grafted from metal‐free photosensitive carbon nitride nanosheets (CN) by dehydration reaction between pendant amino groups from CN and carboxyl groups of functional phenanthroline ligands for photocatalytic H 2 evolution in water medium. The cobalt complex unit serves as a cocatalyst to accelerate separation and transferring of photoexcited charge carriers, and reduce overpotential for H 2 evolution. The hybrid catalyst without any precious metals exhibits excellent performance of H 2 evolution (272 μmol g −1 h −1 ) and high stability during photocatalytic reaction. The finding not only develops a facile way to prepare high‐performance low‐cost photocatalysts for photocatalytic H 2 production, but also provides a new insight into optimizing the interface between cocatalysts and photosensitizers for photocatalytic reaction by grafting active sites directly from semiconductors.