... make metallic nano cobalt powder Fe,Cu,Ni,Zn,Ag,Sn,Bi,Co in ranges of 20~1000nm at your requirement ... . Usages metallic nano cobalt powder Fe,Cu,Ni,Zn,Ag,Sn,Bi,CoAppearance: Different particle size nano cobalt powder is black ... requirements. metallic nano cobalt powder Fe,Cu,Ni,Zn,Ag,Sn,Bi,Co