CeO2 Nanodots@carbon Sphere/NiFe-Layered Double Hydroxides as an Efficient Electrocatalyst for Oxygen Evolution Reactions

CeO2 has rich oxygen vacancies due to its special redox characteristics (Ce4+ to Ce3+), and shows good co-catalytic effects in the catalytic reaction. However, the low conductivity and large size of CeO2 limit its application in electrocatalytic reactions. In this work, CeO2 nanodots are uniformly grown in situ on the surface of carbon spheres by a simple hydrothermal method. The in situ coupling of CeO2 nanodots and carbon spheres (CB) not only provides richer surface defects and larger specific surface areas, but also improves the electrical conductivity and obtains optimized electronic structures. When CeO2@CB is hybridized with NiFe-layered double hydroxides (NiFe-LDHs), which is the typical oxygen evolution catalyst, the CeO2@CB/NiFe-LDH electrocatalyst shows improved oxygen evolution reaction (OER) performance, with a lower overpotential of 203 mV at current density of 20 mAcm−2 in 1.0 M KOH. Therefore, this work provides a promising strategy for the construction of efficient co-catalysts.