Fluorine-Doped rGO-Modified Cu Electrode for Efficient Electrocatalytic CO2 Reduction

Oxide-derived Cu catalysts with multiple chemical states have been shown to promote C-C coupling in electrochemical reduction of CO ₂ (CO ₂ RR) for forming valuable multi-carbon product, but their scalability has been strongly limited by using complex templates or reducing agents. In this work, we propose a simple yet highly controllable synthetic strategy to construct the fluorine-doped reduced graphene oxide (F-rGO) modified Cu electrodes, which shows good activity for the production of C ₂ products in CO ₂ RR. XRD and XPS analyses reveal that the introduction of F-rGO stabilizes the Cu/CuO heterostructure and promotes the partial conversion of Cu ²⁺ into Cu ⁺ /Cu ⁰ , in which metallic Cu, Cu ⁺ species, and F-rGO act cooperatively to optimize intermediate adsorption and suppress competing hydrogen evolution, finally leading to significantly improved CO ₂ RR activity and product selectivity. The optimized F-rGO-Cu-60 + 60 µL electrode thus achieves a stable current density of approximately − 20 mA cm ^− 2 at − 1.0 V vs RHE, delivering a high C ₂ (C ₂ H ₄ , C ₂ H ₆ , and C ₂ H ₅ OH) Faradaic efficiency of 39% and a total carbon-based Faradaic efficiency (CO, formate, and C ₂ products) of 72%.