Enabling highly efficient electrocatalytic oxygen reduction and evolution reaction by established strong MnO/Co-support interaction

Exploring a facile and cost-efficient approach to synthesize electrocatalysts that promoting the interconversion between H 2 O and O 2 remains a crucial challenge. In this work, we report a convenient and effective strategy to synthesis Co metal and MnO immobilized on carbon nanotubes (MnO/Co-CNTs) vis strong metal-support interaction (SMSI). The CNTs support anchored abundant MnO/Co nanoparticles (NPs) in a small size of ~2 nm, when the strong interaction between them suppressed the homogeneous nucleation of MnO/Co during high temperature sintering. Thus, enormous well-dispersed catalytic active sites are produced on the conductive CNTs. Together with the boosted charge transfer between MnO/Co and support, the catalytic activity of MnO/Co-CNTs is eventually significantly promoted. The catalyst shows an efficient oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline solution. Furthermore, SMSI alleviate the agglomeration of NPs and secure the active sites during electrochemical reactions, which account for the enhanced catalytic durability for ORR, OER and HER. In consequence, the MnO/Co-CNTs catalyst shows excellent performance for rechargeable Zn-air battery, and can be utilized to catalyze overall water splitting to produce hydrogen and oxygen. This work manifests a promising approach for optimizing the catalytic performance of the NPs. Superior nonprecious MnO/Co-CNTs bifunctional oxygen electrocatalyst was successfully fabricated through strong metal-support interactions. The extremely outstanding catalytic activities of the as-developed MnO/Co-CNTs were ascribed to the enormous well-dispersed catalytic active sites and the boosted charge transfer between MnO/Co and carbon nanotubes support. Impressively, the as-fabricated rechargeable Zn-air battery afforded an extremely high charge/discharge stability. • MnO/Co-CNTs oxygen electrocatalyst was obtained by strong metal-support interaction. • Well-dispersed catalytic active sites, geometric and electronic modification gave rise to superb electrocatalytic activity. • MnO/Co-CNTs afforded excellent performance for rechargeable Zn-air battery.