The efficiency of the oxidation of carbon nanofibers with various oxidizing agents

SALDI-MS Signal enhancement using oxidized graphitized carbon black nanoparticles

“…This observation is in agreement with findings showing that a concentrated H 2 SO 4 /HNO 3 mixture cuts carbon nanotubes [8] and nanofibers [16] into shorter lengths. The particles of oxidized GCB have a tendency to aggregate, as shown in Figure 1b.…”

“…GCB, which is obtained by heating carbon black at 2700 -3000°C, has a relatively small proportion of residual oxygen on the surface, mainly as a result of contamination of the particles before graphitization [17]. To increase the amount of chemisorbed oxygen on the surface, a concentrated H 2 SO 4 /HNO 3 mixture was used, based on findings from carbon nanofibers [16].…”

Enhancing effect of KMnO4 oxidation of carbon nanotubes network embedded in elastic polyurethane on overall electro-mechanical properties of composite

“…Typically, the nanotube wet oxidation by the potassium permanganate (KMnO 4 ) produces carboxylic acid groups (-COOH) on nanotube surface as well as a significant amount of other oxygenated functional groups such as hydroxyl (-OH) and carbonyl (=O) groups [1,2]. The oxidation enhances gas sensing properties of nanotubes toward organic vapors which can be attributed to better affinity of vapors to the oxidized form of nanotubes [3].…”

“…The network structure results from fine nanotube aqueous dispersion, and thus deposition of individual nanotubes and/or only small nanotube agglomerates on filtrating membrane since the presence of oxygen-containing groups facilitates the exfoliation of nanotube bundles and increases their dispersion in polar media [1,2,5].…”

An efficient method for the carboxylation of few-wall carbon nanotubes with little damage to their sidewalls

“…For example, Liu et al [20] first reported the severe oxidative treatment of SWNT when using a reflux mixture of concentrated sulfuric and nitric acids (H 2 SO 4 /HNO 3 3:1, 98% and 40% respectively). Interestingly, variations of this method have been widely used by various researchers to purify (removal of catalyst impurities and amorphous carbon) and functionalize SWCNT and MWCNT [16,17,20,21,24]. González-Guerrero et al [25] found that the concentration of total acidic groups increased up to 2.5 Â 10 À5 mol mg À1 after 6 h of refluxing time, and remained constant at longer refluxing periods.…”