Cobalt-Backboned Oligomer for Record Photocatalytic CO₂ Conversion to Ethanol

Solar-driven conversion of CO₂ into value-added products is promising for renewable energy storage and carbon neutrality. Although current photocatalysts demonstrate the capability to convert CO₂ into multiple carbon products including ethanol, their performance is limited by high C─C coupling energy barrier and inefficient intermediate enrichment. Here we synthesize a cobalt-backboned oligomer as an efficient photocatalyst to generate a record-high ethanol production rate of 497 µmol/(g·h) for CO₂ photoreduction. It also maintains high performance in cases with simulated industrial flue gas with ∼15% CO₂ and a Martian-like atmosphere with ∼95% CO₂. These properties stem from unique electronic modulation through metal–metal bonding and intermolecular assembly for high-activity reaction channels. This atomically precise cobalt-backboned oligomer opens a new avenue for designing photocatalysts.