Electrified Carbon Cycling for Neutralizing the Steelmaking Industry

ABSTRACT The conventional steelmaking process emits 1.8 tons of CO 2 to produce 1 ton of crude steel, making the steel industry the world's largest emitting manufacturing sector. Here, we propose and demonstrate a renewable route based on electrified carbon cycling, which significantly reduces CO 2 emission by 83%. The critical step of the route involves electrochemical CO 2 reduction (CO 2 RR) to produce CO‐rich syngas, which reduces iron ore into metallic iron (Fe x O y ‐to‐Fe), effectively closing the carbon cycling. A technoeconomic analysis (TEA) reveals that the energy efficiency of this novel process is dependent on the operating parameters of CO 2 RR, with optimal efficiency occurring at the current density range of 150‐200 mA cm −2 . As a proof‐of‐concept study, sulfur vacancy (V S )‐engineered Ag 3 CuS 2 was developed as a high‐performance CO 2 RR electrocatalyst. This catalyst yields a CO‐rich syngas at a high Faradaic efficiency ( FE ) close to 100% at a cell voltage of 2.5 V. The CO 2 RR‐produced syngas effectively reduced iron oxide into metallic iron. The implementation of electrified carbon cycling significantly increases the utilization of electricity in steel production, reaching 88.7%. This research describes a sustainable way to reshape the ironmaking process and ultimately neutralize the steel industry.