Catalytic Consequence of the Interface Between Iron Catalysts and Foils in Synthesis of Aligned Nanocarbons on Foils

Abstract

Growth of aligned carbon nanotubes on different substrates such as titanium, copper, stainless steel and graphite foils has been investigated by different characterization techniques such as SEM, TEM, contact angle measurements and Raman spectroscopy. The study aims at gaining a better understanding of the effects of the surface properties of the foils on the alignment, diameter distribution, structure and the yield of nanocarbons. The results revealed that the surface tension of the foils has a significant influence on the size of the Fe catalyst particles on the foil surfaces obtained by ferrocene decomposition. The size of the Fe particles directly determined the structure and alignment of the nanocarbons on the foils. Small sized (about 10 nm) and highly crystalline carbon nanotubes were produced on foils such as Al and Ti with the low surface tension, while it is hard to grow any nanocarbon on the Cu foils due to too high surface tension. Lowering the surface tension of the Cu foils by surface oxidation made it possible to grow carbon nanofibers.