Spinel Metal Oxide CoFe₂O₄as A Bi-functional Electrocatalyst For Oxygen Electrode

In this paper, cobaltite spinel oxide CoFe2O4was studied as a bi-functionalelectrocatalyst for air electrode (oxygen electrode) of metal-air batteries. This paper focuson designing and synthesizing CoFe2O4nanomaterials as efficient bi-functionalelectrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER).In order to improve the electrical conductivity of CoFe2O4and to improve the transport ofreactants and products in the triple phase (solid-liquid-gas) of the oxygen electrode,CoFe2O4/carbon nanocomposites were prepared. In this way, a new applicable bi-functional electrocatalysts are expected for metal-air batteries. The mechanism of the ORRand OER on the CoFe2O4/carbon nanocomposites is elucidated. These studies will lay asolid experimental foundation for designing and preparing highly active spinel metal oxideelectrocatalysts for the ORR and OER. The CoFe2O4/graphene (carbon nanotube)nanohybrids were prepared by an electrostatic assembly method combining with ahydrothermal method. The electrocatalytic activity and stability of ORR and OERperformance was evaluated on CoFe2O4/graphene (carbon nanotube) nanohybrid. Theeffect of the coupling between CoFe2O4and graphene (carbon nanotube) on the bindingenergy of Co, Fe and O as well as the ORR and OER activity of CoFe2O4/graphene (carbonnanotube) nanohybrid was investigated. In addition, the CoFe2O4nanowires weresynthesized via a template method by using SBA-15as a template. The catalytic activitiesof CoFe2O4nanowires toward ORR and OER were studied.