Catalytic performance of graphdiyne for CO₂ reduction and charge dynamics progress

Graphdiyne (GDY) is a new two-dimensional carbon allotrope, recognized as a promising material for photocatalytic CO₂ reduction because of its unique sp-sp² hybridized network and tunable bandgap and extraordinary charge transport characteristic. The growing requirement for sustainable CO₂ conversion processes has fueled tremendous research activities on GDY-based photocatalysts, due to their improved light harvesting potential, charge separation capabilities, and catalytic site availability as compared to traditional materials. Herein, we review the recent progress on GDY-based strategies in CO₂ reduction with an argument towards GDY metallation, metal-free GDY, heterostructures including GDY, and theoretical studies. In situ spectroscopic studies along with density functional theory (DFT) calculations provide mechanistic insights into the decisive pathways behind CO₂ activation, charge transfer, and product selectivity. This review is a comprehensive discussion extended on the synthetic methodologies and new computational insights that bring forth a rational basis for designing next-generation GDY-based photocatalysts. Integrating experimental advances with theoretical understanding, this work provides a roadmap for bridging the gap between materials design and practical photocatalytic application, providing perspectives on challenges and opportunities for GDY-based CO₂ conversion technologies in the future.