Upcycling electronic waste drives the design of defective in-based catalysts toward efficient electrochemical CO2 reduction

Upcycling e-waste to enable efficient catalyst synthesis offers a sustainable pathway for solid waste management and the advancement of green catalysis. However, reconciling high catalytic performance with e-waste-derived materials remains challenging. Here, we report a low-cost, defect-engineered InOOH electrocatalyst derived from electronic waste (ew-InOOH/Vo-Sn), which is modulated through Sn incorporation and oxygen vacancy (Vo) engineering using In-dodecylamine (In-DDA) complexes derived from spent liquid crystal display panels (s-LCD), for the electrochemical CO 2 reduction reaction (eCO 2 RR). The material was rationally synthesized through theory-guided optimization of InOOH via Sn-incorporation and vacancy engineering, combined with the utilization of In-DDA complexes obtained from s-LCD leachates using a thiol-assisted wet-chemical strategy. At −0.97 V vs RHE, the ew-InOOH/Vo-Sn delivered a high formate Faradaic efficiency (FE formate ) of 92.8%, closely approaching that of the corresponding sample prepared from pure metal-salt precursors (ms-InOOH/Vo-Sn, 94.5%) under identical synthetic conditions, and comparable to the majority of In-based eCO 2 RR catalysts reported in the literature. Mechanistic insights reveal that Sn-incorporation stabilizes Vo in InOOH and synergistically alters the electronic states of neighboring In atoms, which strengthens CO 2 adsorption while optimizing the adsorption energetics of *OCHO and H* intermediates. Our findings demonstrate a sustainable pathway to design In-based electrocatalysts from electronic-waste, integrating resource recycling with energy conversion.