Preparation of nano NiO by pyrolytic decomposition of NiC_2O_4·2H_2O in the air

The process of pyrolytic decomposition of NiC_2O_4·2H_2O in the air was analyzed by TG-DSC,SEM and TEM.The research results showed that there are two stages in the process of pyrolytic decomposition of NiC_2O_4·2H_2O in the air.Firstly,the crystal water in NiC_2O_4·2H_2O was lost to generate NiC_2O_4 at 175～275℃. Secondly,NiC_2O_4 was generated into NiO through pyrolytic decomposition at 325～400℃.In the process of preparing NiO by pyrolytic decomposition of NiC_2O_4·2H_2O in the air,the morphology of products of pyrolytic decomposition changes greatly at 246.5～357.8℃,little at 357.8～400.0℃.The pyrolytic decomposition conditions could be controlled in stages to effectively control the morphology of NiO.The pyrolytic decomposition of NiC_2O_4·2H_2O was performed in the air at the heating rate of 10℃/min,then the heat insulation was performed at 400℃for 10min to prepare the spherical NiO of about 5nm.