Ultrathin In-Plane Heterostructures for Efficient CO₂ Chemical Fixation

Chemical fixation of carbon dioxide (CO₂ ) into value-added organics is regarded as a competitive and viable method in large scale industrial production, during which the catalysts with promoting CO₂ activation ability are needed. Herein, we proposed an in-plane heterostructure strategy to construct Lewis acid-base sites for efficient CO₂ activation. By taking ultrathin in-plane Cu₂ O/Cu heterostructures as a prototype, we show that Lewis acid-base sites on heterointerface can facilitate a mixed C and O dual coordination on surface, which not only strengthen CO₂ adsorption, but also effectively activate the inert molecules. As revealed by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and quasi in situ X-ray photoelectron spectroscopy (XPS), Lewis acid-base sites could readily activate CO₂ to ^. CO₂ ^- species, which is the key intermediate radical for CO₂ fixation. As a result, abundant Lewis acid-base sites endow Cu₂ O/Cu nanosheets with excellent performances for dimethyl carbonate generation, a high conversion yield of 28 % with nearly 100 % selectivity under mild conditions. This study provides a model structure for CO₂ fixation reactions.