Catalyst support of air cathode requires stable structure and high specific surface area, due to the unique semi open structure of metal-air battery. Herein, we prepare a novel 3D Copper/Carbon film catalyst support with dual 3D porous structure by nonsolvent induced phase separation and heat treatment process. During the heat treatment process in inert atmosphere, copper atom diffuses and recrystallizes to form the 3D porous structure with the support of polyacrylonitrile, and the polyacrylonitrile is carbonized to construct superimposed 3D carbon networks. This dual 3D porous Copper/Carbon f...