▎ 摘　　要

NOVELTY - Manganese dioxide composite porous graphene cathode catalyst comprises a matrix and a composite material combined with the matrix, where the matrix comprises porous reduced graphene oxide, and the composite material comprises manganese dioxide and the mass ratio of manganese dioxide to the porous reduced graphene oxide is 10:1-1:10. USE - The manganese dioxide composite porous graphene cathode catalyst is used as battery cathode oxygen reduction catalyst of a lithium-air battery (claimed). ADVANTAGE - The porous graphene cathode catalyst: has a unique pore structure, high-efficiency bifunctional ORR and OER activity, synergistic combination, high discharge specific capacity, and good cycle capability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the porous graphene cathode catalyst comprises (i) mixing the graphene oxide powder with the solvent to obtain the dispersion liquid a; adding template b to the dispersion liquid a to obtain dispersion liquid c, carrying out solvent thermal reaction, then filtering, washing and drying to obtain solid powder d, carrying out heat treatment to the solid powder d to obtain the porous reduction graphene oxide e; (ii) uniformly mixing the manganese dioxide precursor according to the stoichiometric coefficient with the porous reducing graphene oxide e dispersion liquid, carrying out solvent thermal reaction in the isopropanol solution to obtain the manganese dioxide composite porous reducing graphene oxide f; and (iii) manganese dioxide composite porous reduction graphene oxide f by water and ethanol alternately pumping, filtering and cleaning, and vacuum drying.