Co0−Coδ+ Interface Double‐Site‐Mediated C−C Coupling for the Photothermal Conversion of CO2 into Light Olefins

Co⁰−Co^δ+ interfacial double sites exhibit excellent selectivity toward light olefins during the hydrogenation of CO₂ enhanced by light irradiation when compared with pure metallic Co. Owing to the interfacial effect, Co⁰−Co^δ+ exhibits a lower hydrogenation ability than metallic Co, tuning a pathway with a manageable activation barrier for C−C coupling.

Abstract

Solar-driven CO₂ hydrogenation into multi-carbon products is a highly desirable, but challenging reaction. The bottleneck of this reaction lies in the C−C coupling of C₁ intermediates. Herein, we construct the C−C coupling centre for C₁ intermediates via the in situ formation of Co⁰−Co^δ+ interface double sites on MgAl₂O₄ (Co−CoO _x /MAO). Our experimental and theoretical prediction results confirmed the effective adsorption and activation of CO₂ by the Co⁰ site to produce C₁ intermediates, while the introduction of the electron-deficient state of Co^δ+ can effectively reduce the energy barrier of the key CHCH* intermediates. Consequently, Co−CoO _x /MAO exhibited a high C_2–4 hydrocarbons production rate of 1303 μmol g⁻¹ h⁻¹; the total organic carbon selectivity of C_2–4 hydrocarbons is 62.5 % under light irradiation with a high ratio (≈11) of olefin to paraffin. This study provides a new approach toward the design of photocatalysts used for CO₂ conversion into C₂₊ products.

Zum Volltext