Catalyst comprising cobalt core and carbon shell for alkaline oxygen reduction and method for preparing the same

A method for preparing a catalyst, consisting of:

• (a) preparing a dispersion by dispersing a carbon support in a solvent;
• (b) preparing a mixture solution by mixing the dispersion with a cobalt precursor and oleylamine;
• (c) preparing a catalyst precursor by heat-treating the mixture solution at a low temperature of 250-350° C. under an inert gas atmosphere, wherein an oleylamine-coated cobalt oxide nanoparticle is supported on the carbon support in the catalyst precursor;
• and
• (d) preparing a catalyst by heat-treating the catalyst precursor at a high temperature of 550-800° C. under the inert gas atmosphere, wherein the catalyst contains the carbon support and a core-shell nanoparticle supported on the carbon support,
• wherein the core of the core-shell nanoparticle is cobalt metal without having the heterogeneous element and the shell of the core-shell contains carbon.