Unveiling the Photocatalytic Potential of Heteroatom-Rich Luminescent Carbon Dots for Green H ₂ Production

Carbon dots (CDs) have emerged as a recent class of luminescent nanomaterials due to their unique photoluminescence properties and biocompatible nature. Despite extensive studies on their photophysical properties, the photocatalytic activity of CDs, especially the crucial role of heteroatom functionality in governing their optoelectronic properties, has not been explored much. This perspective highlights recent advances in the photocatalytic activity of heteroatom functionalized luminescent CDs especially for green H2 production. Incorporation of heteroatom functionalities (e.g., N, P, B, S, etc.) in CDs can modulate the optoelectronic features of CDs, enhancing visible light absorption and promoting photogenerated charge separation. Furthermore, rational tuning of the heteroatom functionalities improves the catalytically active sites and selective photoinduced free carrier accumulation on CDs’ surface which are essential for photocatalysis. Consequently, a traditional metal cocatalyst can be replaced simply by a heteroatom functionality in CDs which can enable simultaneous oxidative and reductive half-reactions without the need for complex heterojunction architectures, which is the major bottleneck for conventional photocatalytic systems. Overall, the present perspective demonstrates those above-mentioned strategies in detail along with the current challenges and future prospects of CDs as sole photocatalysts especially for photocatalytic green H2 production.