Enhanced photocatalytic hydrogen evolution by partially replaced corner-site C atom with P in g-C₃N₄

Modifying the structure of photocatalyst to tune its electronic and physicochemical properties is an effective approach for efficient photocatalysis. Herein, we modify the structure of g-C₃N₄ by partially replacing the corner site C atom with P heteroatom via a simple thermal phosphorization method. Comparing with the pristine g-C₃N₄, the g-C₃N₄ after phosphorization shows an improved photocatalytic hydrogen activity, which is attributed to the narrowed bandgap and the upshifted conduction band edge, enhanced separation and transfer of photogenerated charges, and highly hydrophilic surface absorbing reactant molecule for photocatalysis. Various experimental characterizations are conducted to systemically explore the underlying essential mechanism behind the superior photocatalytic performance of g-C₃N₄ with phosphorization treatment. This work provides a simple approach to modifying the structure of g-C₃N₄, which could be applied to other semiconductors for designing photocatalyst with unique structure and enhanced activity.