Precious-Metal-Free CO₂ Photoreduction Boosted by Dynamic Coordinative Interaction between Pyridine-Tethered Cu(I) Sensitizers and a Co(II) Catalyst

Improving the photocatalytic efficiency of a fully noble-metal-free system for CO2 reduction remains fundamental challenge, which can be accomplished by facilitating electron delivery as consequence exploiting intermolecular interactions. Herein, we have designed two Cu(I) photosensitizers with different pyridyl pendants at phenanthroline moiety to enable dynamic coordinative interactions between sensitizers and cobalt macrocyclic catalyst. Compared parent photosensitizer, one pyridine-tethered derivatives boosts apparent quantum yield up 76 ± 6% 425 nm selective (near 99%) CO2-to-CO conversion. This value is nearly twice that no (40 5%) substantially surpasses record (57%) systems reported so far. also realizes maximum turnover number 11 800 1400. In contrast, another in pyridine substituents are directly linked moiety, inactive. The above behavior mechanism systematically elucidated transient fluorescence, absorption, X-ray absorption spectroscopies, chemical calculations. work highlights advantage constructing fine-tune transfer processes within photoreduction.