Studies On The Synthesis Of Carbon Nanotubes With Different Methods

Since the discover of carbon nanotubes(CNTs),they have attracted much attention from scientists in the field of electronic material,hydrogen storage material,especially,catalyst support material for their unique and novel structure.My objects are how to synthesize the carbon nanotubes with large core and thin wall,then apply them as catalyst support material.A method of chemical vapor deposition(CVD) was employed to prepare CNTs from catalytic decompostion of methane with three different catalysts .During the process of experiments,some characters of catalysts and carbon nanotubes were investigated by XRD,TEM,SEM,BET,TPR and TG.First ,Ni-Cu-Al catalyst was used. During the preparation of this catalyst,the content of Cu was an important factor,as well as the bake temperature and atmosphere of catalysts.As a result,carbon nanotubes with good shape and high yields was produced by catalyst with 15% Cu content.In addition,products'inner diameter can arrive to 60nm by adding some sodium carbonate power(350 mesh size) to catalysts.Secondly,carbon nanotubes was used as catalyst support to produce fresh carbon nanotubes superior to other support material.And that carbon nanotubes were treated by nitric acid or potassium hydroxide before supporting will load and disperse the active elements well.Thirdly,high-dense carbon nanotube arrays growed in template of anodic aluminun oxide(AAO) loading Ni-base catalyst.The result showed that carbon nanotubes obtained had an indentical diameter to template pore about 100 nm,as well as ,thin walls and straight tubes by TEM.Meanwhile,Effects of anodic time to pore depth and anodic voltage to pore size also were studied.