Unlocking the Potential of Biomass Residues for the Sustainable Synthesis of Photocatalysts for H2 Generation

Biomass-derived materials are attracting increasing interest for photocatalytic photoreforming due to their ability to function as photocatalysts, co-catalysts, supports, templating agents, and green reducing agents. This review examines recent advances in the development of biomass-derived photocatalysts, including biochar, hydrochar, carbon quantum dots, graphene-like carbons, heteroatom-doped porous carbons, and biomass-derived graphitic carbon nitride, highlighting the relationships between synthesis strategies, structural properties, and photocatalytic performance. The multifunctional role of biomass-derived materials in enhancing semiconductor dispersion, interfacial charge transfer, and charge-carrier separation is also discussed. Finally, current challenges are identified, including the limited number of intrinsically active biomass-derived photocatalysts, the incomplete understanding of structure-activity relationships, and the lack of standardized evaluation protocols, providing perspectives for the rational design of efficient and scalable photocatalysts for solar-driven photoreforming.