Fly ash was used as catalytic support for carbon nanotubes(CNTs)growth by chemical vapor deposition(CVD)due to having ideal compositions(SiO2,Al2O3,and Fe2O3).In this paper,CNTs were synthesized on Ni catalyst/fly ash...Fly ash was used as catalytic support for carbon nanotubes(CNTs)growth by chemical vapor deposition(CVD)due to having ideal compositions(SiO2,Al2O3,and Fe2O3).In this paper,CNTs were synthesized on Ni catalyst/fly ash substrate using CVD method.The influence of parameters(e.g.,reaction temperature and gas flow rate)on the carbon yield and structure of the resulting CNTs was on the carbon yield and structure of the resulting CNTs was investigated by thermo-gravimetric analyses,Scanning electron microscopy,and Raman spectroscopy analysis.The results indicated that the growth temperature controlling had a significant effect on the diameter of CNTs.And the proper acetylene and hydrogen flow rate would decrease in defect density and increase in yield of as-grown CNTs on fly ash.Finally,the amorphous carbon on the surface of as-grown CNTs were removed by heating in air.Experimental results showed that the hydrophobic of the annealed CNTs was weak due to introducing functional groups to the surface of CNTs.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant No.51472090)and the Science and Technology Program of Guangzhou(No.201607010047)and the Natural Science Foundation of Guangdong Province(No.2017A030313281).
文摘Fly ash was used as catalytic support for carbon nanotubes(CNTs)growth by chemical vapor deposition(CVD)due to having ideal compositions(SiO2,Al2O3,and Fe2O3).In this paper,CNTs were synthesized on Ni catalyst/fly ash substrate using CVD method.The influence of parameters(e.g.,reaction temperature and gas flow rate)on the carbon yield and structure of the resulting CNTs was on the carbon yield and structure of the resulting CNTs was investigated by thermo-gravimetric analyses,Scanning electron microscopy,and Raman spectroscopy analysis.The results indicated that the growth temperature controlling had a significant effect on the diameter of CNTs.And the proper acetylene and hydrogen flow rate would decrease in defect density and increase in yield of as-grown CNTs on fly ash.Finally,the amorphous carbon on the surface of as-grown CNTs were removed by heating in air.Experimental results showed that the hydrophobic of the annealed CNTs was weak due to introducing functional groups to the surface of CNTs.
