Cu-MOF@Co-MOF derived Co–Cu alloy nanoparticles and N atoms co-doped carbon matrix as efficient catalyst for enhanced oxygen reduction

We prepare a series of N-containing [email protected] core-shell templates by employing two-step feed-in pathway and then step by step calcining these materials to obtain the N-doped carbon layers encapsulated Co–Cu alloy nanoparticles as efficient catalysts for enhanced oxygen reduction. The purpose of Cu-MOF designed as core materials is to increase the number of openly active sites when the templates are calcined at high temperature. During calcining, the Cu atoms facilitate the dispersion of Co on the surface of Co–Cu alloy nanoparticles, which efficiently avoid the agglomeration of Co during carbonization. When being used as cathode oxygen reduction catalysts, the optimal Co–Cu(3:1)@CN-900 material exhibits outstanding performance that can be comparable with the 20 wt% Pt/C catalysts, and the onset potential and half-wave potential of Co–Cu(3:1)@CN-900 is 60 mV and 37 mV higher than that of monometallic [email protected] catalysts, respectively. Moreover, the active sites of Co–Cu(3:1)@CN-900 catalysts are also carefully investigated.