Light-Field Orchestrated Tandem Photothermal Catalysis for Highly Selective CO₂-To-C₂₊ Olefin Conversion

The direct photothermal conversion of CO₂ into multicarbon olefins with high selectivity presents a promising route for sustainable carbon utilization. However, achieving high activity and selectivity simultaneously remains a formidable challenge due to intrinsic trade-offs in catalytic efficiency. Here, we introduce a spatially modulated light-field that orchestrates tandem active sites, enabling one-pot CO₂-to-olefin conversion. Light-field-driven reduction rapidly transforms bimetallic ferrite into alloyed carbide in situ, forming synergistic CoFe oxide/carbide interfaces. At a CO₂ conversion of 39.6%, the optimized system in a batch reactor delivers a C_2-4 olefin productivity of 2.05 mmol g^-1 h^-1, of which 78.5% corresponds to C₂H₄ and C₃H₆, while under flow conditions it achieves a C₂₊ olefin selectivity of 72% among the hydrocarbon products, thereby establishing a benchmark for photothermal CO₂-to-olefin conversion. Mechanistic investigations demonstrate that light-modulated interfacial coupling between oxide and alloy carbide phases dynamically reconfigures the electronic structure of unsaturated CoFe active sites, thereby mitigating mass-transfer limitations during C₁-intermediate hydrogenation and directing selectivity toward C₂₊ olefins. Furthermore, scalability tests confirm the feasibility of this approach, as an integrated reactor system produces 66.1 L m^-2 of C_2-4 olefins per day under ambient sunlight. This work paves the way for advanced light-driven catalytic systems for industrial CO₂ high value-added conversion.