EFFECT OF HYDROCARBON AND TRANSPORT GAS FEEDSTOCK ON EFFICIENCY AND QUALITY OF GROWN SINGLE-WALLED NANOTUBES

摘要

Methods and processes for synthesizing high quality carbon single-walled nanotubes (SWNTs) are provided. The method provides the means for optimization of amount of carbon precursor and transport gas per unit weight of catalyst. Efficiencies of about 20% can be achieved when contacting the catalyst deposited on a support with a carbon precursor gas with a flow rates of about 4.2x10-3 mol CH4/sec-g (Fe) at 780 0C. Hydrocarbon flow rates of about 1.7 10-2 mol CH4/sec-g (Fe) and higher result in faster carbon SWNTs growth with improved quality. Slower rates of carbon atoms supply (~4.5x lO20 C atoms/s-g Fe or 6.4x 10-4 mol CH4/sec-g (Fe)) result in the formation of more defective nanotubes.