Graphdiyne facilitates photocatalytic CO2 hydrogenation into C2+ hydrocarbons

Graphdiyne (GDY) is firstly introduced to the gaseous photocatalytic CO2 hydrogenation system for C2+ production, in which a GDY-modified In2O3 nanocomposite (denoted as GDY-IO) is fabricated by simple electrostatic attraction and thermal treatment routes. GDY-IO delivers much higher performance for CO2 hydrogenation compared to that of pristine In2O3, reflecting by the significantly improved C1 (CO and CH4) yield and the newly formed C2+ hydrocarbons (C2H4, C2H6, C3H6, and C3H8). The introduction of GDY promotes the transport of photogenerated holes from In2O3 to GDY and suppresses the recombination of photogenerated carriers, thereby gathering abundant electrons to participate in the CO2 hydrogenation reaction. GDY-IO interface may stabilize the key HOCH* intermediate and significantly reduce the kinetics barrier to avail CH* formation, tuning the subsequent hydrogenation and C-C coupling into thermodynamically favorable exothermal processes. This research develops a new avenue for synthesis of high value-added chemical fuels from greenhouse gases by graphdiyne-based photocatalysis.