Regulating the Magnetic Domain of Nickle for Enhanced CO₂ Electrochemical Reduction Driven by External Magnetic Field

Abstract Electrochemical reduction of carbon dioxide (CO 2 RR) into valuable fuels and chemicals is a highly desirable approach for achieving carbon neutrality, but it faces substantial technical hurdles. Herein, a novel ferromagnetic Ni@NC electrocatalyst is reported, composed of nickel nanoparticles embedded within a nitrogen‐doped carbon matrix. The optimal Ni@NC catalyst displays a fourfold increase in current density at 140 versus 0 mT in H‐type cell and achieves nearly 100% CO Faradaic efficiency (FE CO ) across a wide potential range with minimal overpotential in flow cell. Quantum diamond atomic force microscopy (QDAFM) directly demonstrates the orderly magnetic moments of the Ni@NC catalyst under the external magnetic field. Further theoretical calculations reveal that the orderly magnetic moments induced by the external magnetic field facilitate the formation of Ni–O–Ni and reduce the energy barriers of COOH * intermediates. This study underscores the potential of applying magnetic field modulation to not only enhance the catalytic efficiencies but also extend this strategy to other catalytic systems.