National Research Council of Canada. Measurement Science and Standards
National Research Council of Canada
Activation analysis; Carbides; Carbon nanotubes; Catalysts; Inductively coupled plasma mass spectrometry; Isotopes; Laser ablation; Lead; Mass spectrometers; Mass spectrometry; Mercury (metal); Molybdenum; Neutron activation analysis; Nickel; Trace analysis; Trace elements; ICP-MS; Metal content determination; Microwave-assisted acid digestion; Microwave-induced combustion; Ni and co catalysts; SWCNT; Trace metal impurities; Single-walled carbon nanotubes (SWCN)
A single-wall carbon nanotube material produced by laser ablation of renewable biochar in the presence of Ni and Co catalyst was characterized for residual catalyst (Co and Ni) as well as trace metal impurity content (Fe, Mo, Cr, Pb and Hg) by isotope dilution ICP-MS following sample digestion. Several matrix destruction procedures were evaluated, including a multi-step microwave-assisted acid digestion, dry ashing at 450 C and microwave-induced combustion with oxygen. Results were benchmarked against those derived from neutron activation analysis and also supported by solid sampling continuum source GF-AAS for several of the elements. Although laborious to execute, the multi-step microwave-assisted acid digestion proved to be most reliable for recovery of the majority of the analytes, although content of Cr remained biased low for each approach, likely due to its presence as refractory carbide.
Spectrochimica Acta - Part B Atomic Spectroscopy105, no. 1 March 2015 (18 October 2014): 89–94.