Nickel complex co-catalyst confined by chitosan onto graphitic carbon nitride for efficient H2 evolution.

Developing earth-abundant H2-production heterogeneous photocatalysts with robust activity and stability has attracted great interests. Herein, a low-cost photocatalyst was prepared by binding nickel complex covalently from primary amines of chitosan (NiL) onto photosensitive carbon nitride nanosheets (CN) through electrostatic interaction. Introduction of NiL results in more efficient utilization of solar energy, photogenerated electrons' direct transfer and lower overpotential for water reduction. The optimized NiL3-CN photocatalyst shows the highest H2 evolution rate of 346 µmol g-1 h-1 under visible light irradiation and exhibits high stability during test. This work presents great potentials for sustainable conversion of solar energy, and sheds positive light on the development of heterogeneous photocatalysts via anchoring H2-evolving molecule catalysts confined by inexpensive macromolecules onto a semiconductor photosensitizer through a facile and valid method.