In Situ High Selectivity Contact-Electroreduction of CO2 to Methanol Using an Imine-Mediated Metal-Free Vitrimer Catalyst.

Metal catalysts for the CO2 reduction reaction (CO2RR) face challenges such as high cost, limited durability, and environmental impact. Although various structurally diverse and functional metal-free catalysts have been developed, they often suffer from slow kinetics, low selectivity, and nonrecyclability, significantly limiting their practical applications. In this study, we introduce a recyclable nonmetallic polymer material (vitrimer) as a catalyst for a new platform in contact-electrocatalysis. This approach harnesses the contact charges generated between water droplets and vitrimer to drive CO2RR, achieving methanol selectivity exceeding 90%. The imine groups within the vitrimer play a dual role, facilitating CO2 adsorption and enriching friction-generated electrons, thereby mediating efficient electron transfer between the imine groups and CO2 to promote CO2RR. After 84 h of CO2RR, the system achieved a methanol production rate of 13 nmol·h-1, demonstrating the excellent stability of the method. Moreover, the vitrimer retains its high-performance electrocatalytic activity even after recycling. Mechanistic studies reveal that, compared to traditional metal catalysts, the N─O bond in the imine, which adsorbs the key intermediate *OCH3, breaks more readily to produce methanol, resulting in enhanced product selectivity and yield. This efficient and environmentally friendly contact-electroreduction strategy for CO2 offers a promising pathway toward a circular carbon economy by leveraging natural water droplet-based contact-electrochemistry.