Contact-Electrocatalytic CO ₂ Reduction via Solid–Liquid–Gas Interfaces Involving Liquid Metals

Excessive carbon dioxide (CO2) emissions are accelerating global climate deterioration, necessitating the development of green methods for converting it into valuable carbon-based materials. However, the thermodynamic stability and kinetic inertness of CO2 make its activation face grand challenges, requiring the collaborative advancement of new materials and advanced technologies. Liquid metals (LMs) possess both metallic and fluidic properties, offering unique opportunities due to their oxygen adsorption capacity and mechano-electrochemical activity. Herein, we introduce a triphase system composed of LMs, polytetrafluoroethylene (PTFE), and CO2. This system leverages differentiated electronic states at the multiphase interface to manage contact electrification, effectively converting CO2 into solid carbon products. The strategy generates highly reactive reducing electrons at the solid–liquid interface through a force-electrochemical coupling mechanism, thereby circumventing traditional electrocatalytic power inputs. This innovative approach, based on the liquid metals contact-electrocatalytic (LMs-CEC), directly converts mechanical energy into chemical energy, overcoming the high-energy input required in the conventional carbon conversion processes. Our approach will offer a promising solution for the green conversion of CO2, which could advance carbon-negative technologies.