Target High-Efficient Ethylene Production from Dilute CO2 Enabled by Sustainable Contact Electrons

Abstract

The electrochemical CO₂ reduction reaction (CO₂RR) exhibits significant potential to efficiently convert CO₂ into ethylene (C₂H₄). However, achieving high C₂H₄ selectivity remains a considerable challenge due to the difficulty in effective C─C coupling and stringent requirements on CO₂ purity. Herein, a novel contact-electro-catalysis method for CO₂RR is presented by constructing dual-active-site catalysts on the electronegative tribolayer of a triboelectric nanogenerator (TENG), including single copper atom anchored polymeric carbon nitride (Cu─PCN) and CuO nanoparticle, achieving an outstanding C₂H₄ Faradaic efficiency of 63.5% in dilute CO₂. Experimental and theoretical studies indicate that Cu─PCN active sites exhibit the ability to heighten ^*H adsorption and facilitate its migration into CuO nanoparticles. This process effectively modulates the coverage of ^*H on CuO and promotes the transformation of ^*CO into ^*CHO. Subsequently, ^*CHO undergoes dimerization on the CuO surface, ultimately yielding C₂H₄. Furthermore, the electric field generated by the TENG enhances the coverage of ^*H and ^*CO on both the Cu─PCN and CuO surfaces, which subsequently reduces the energy barrier for C─C coupling. This work provides a new route to enhance the selective reduction of CO₂ to C₂H₄ by integrating contact electrocatalysis with dual active site technologies.