Cu-Doped C3N4 for Optimized Charge Separation and Efficient Photocatalytic Hydrogen Production

Photocatalytic hydrogen production represents a highly promising strategy for sustainable energy development. Among conventional photocatalysts, graphitic carbon nitride (g-C3N4) is distinguished by its non-toxicity and cost-effectiveness. However, its inherent limitations, particularly the high surface transfer barrier, result in poor charge-carrier separation. In this study, copper (Cu) was successfully incorporated into the C3N4 framework via a facile in-situ self-assembly method, significantly mitigating the interfacial resistance of the pristine material. The optimized Cu/C3N4 catalyst exhibited a remarkable hydrogen evolution rate of 1.5 mmol·g-1·h-1, which is 3.3-fold that of pure C3N4 (0.45 mmol·g-1·h-1). Mechanistic insights reveal that Cu doping not only facilitates electron transfer between triazine rings but also broadens the light absorption range and promotes carrier separation, thereby markedly augmenting the photocatalytic hydrogen evolution activity.