The composite material of multi-walled carbon nanotubes/metal phthalocyanine may have potential applications in diverse fields,for example in nanodevices,sensors.Raw multi-walled carbon nanotubes (MWCNTs) were first refluxed in 2.6 M nitric acid,followed by washing with de-ionized water,and dried.Then the purified multi-walled carbon nanotubes (MWCNTs) were refluxed in concentrated nitric acid for 12 hours at 130℃.Atter this treatment,carboxylic acid groups are expected to be the predominant species on the opened caps and defect sites.At the same time,cobalt(Ⅱ) tetranitrophthalocyanine (CoTNPc) was synthesized in pentanoi under the protection of nitrogen gas,using 4-nitrophthalonitrile and anhydrous cobalt chloride as raw material and DBU as catalyst.Next the cobalt(Ⅱ) tetraaminophthalocyanine (CoTAPc) was produced from the reduction of CoTNPc,using Na2S·9H2O as reductant[1].