Dual-Fluorinated Ni Single Atom Catalyst for Efficient Artificial Photosynthetic Diluted CO2 Reduction

The development of efficient photocatalysts to convert dilute CO₂ from flue gas into high value-added products is a promising approach to achieving carbon neutrality. In this work, a dual-fluorinated Ni single atom photocatalyst is reported for the photoreduction of diluted CO₂ to CO. Under a dilute CO₂ (10%) atmosphere, TPB-SA2F-Ni achieves the highest reported CO yield (30344.4 µmol g⁻¹ h⁻¹) among heterogeneous catalytic systems with a CO selectivity of 98%. Kevin probe force microscopy and photoelectrochemical characterizations indicate that dual-fluorination strategy enhances photoexcited electron transfer between the photosensitizer and photocatalyst by optimizing the conjugated electronic structure. Pore size distribution and CO₂ adsorption experiments show that the uniform microporous structure induced by the dual-F site further enhanced the ability of the Ni-N₂O₂ active site to capture CO₂ molecules. Density functional theory calculations indicate that the high CO yield of TPB-SA2F-Ni stems from a lowered energy barrier for *COOH intermediate formation.