CVD-growth of MWCNT arrays on Me-Ct-N-(O) thin films

Carbon nanotubes (CNT) have a number of attractive chemical, physical, electrical, and mechanical properties [1], making their use promising in various devices, such as field emission devices, optical waveguides, solar cells ,... [ view full abstract ]

Carbon nanotubes (CNT) have a number of attractive chemical, physical, electrical, and mechanical properties [1], making their use promising in various devices, such as field emission devices, optical waveguides, solar cells , sensors, fuel cells, supercapacitors, lithium-ion batteries, and others.[2].
CNTs are produced in electric arc discharge between carbon electrodes or laser ablation of graphite [1,2]. However, with regard to the integrated technologies for different devices a catalytic chemical vapor deposition is the preferred method [1,2], since the CNT growth takes place on the surface of the solid phase in this case. Known catalysts for this process are the metals Fe, Co, Ni, Pd, their alloys, and the alloys of these metals with other transition metals, in which, however, the content of the catalyst is always predominant [3].
In this work we have studied the possibility of using thin film alloys Me-Ct as a catalyst for the growth of the CNT, where Me is a transition metal of IV-VII of the Periodic Table of the Elements, and Ct is catalytic metal for nanotube growth (Fe, Ni, Co, Pd), with the addition of a components, such as nitrogen and oxygen.
It was revealed that the initial film Me-Ct-N- (O) is in an amorphous state. Heating to synthesis temperature leads to full crystallization of the film and appearance of pure solid catalyst particles on the surface. These particles are a source of CNTs. Wherein the content of Ct in the alloy is <40 at.% the attraction of using this alloy as CNT growth catalyst is the ability to control density and diameter of CNTs; good reproducibility and uniformity of the CNT growth process on the area of the substrate surface, in spite of the serious variation in film thickness of the catalyst.
[1] M. S. Dresselhaus et al. Springer-Verlag. (2001). 449 p.
[2] Z. Ren et al. Springer-Verlag. (2013). 299 p.
[3] E.V. Lobiak et al. J.Alloys &Comp. (2015) 621.