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Abstract: The determination of the iodine adsorption number (IN) of carbon black (CB) by using a direct electrochemical reduction method was investigated. The results show that the IN measured by the electrochemical method is close to that obtained by traditional titration methods. A low relative standard deviation (RSD) of ca. 4–5%, for the IN values, shows the high precision of the measurements, while material balance calculation for the iodine in the measurement system confirmed the accuracy of the IN values. These results demonstrate the feasibility and reliability of the direct cathodic reduction method as an analytical method for IN. [ABSTRACT FROM AUTHOR]

One-dimensional nitrogen-doped hollow carbon nanoparticle chains (CNCs) featuring bimodal pore size distribution were obtained by direct thermal pyrolysis of a three-dimensional cyanide-bridged coordination polymer precursor (zinc hexacyanoferrate) without the need for additional carbon, nitrogen, and catalyst sources. Nitrogen doping turned out to play the key role in the formation of mesoporous compartment layers and structural defects in the CNCs. Small mesopores in the walls provided high surface area for charge storage and allowed the migration of electrolyte into the compartments. Large mesopores in the hollow compartments accommodated electrolyte for easy transport of lithium ions. The commercial multiwalled carbon nanotube (CNT) electrode stored lithium ions primarily through the intercalation process, while the CNC electrode stored lithium ions through both the intercalation and adsorption processes. Thus, the CNC electrode exhibited superior supercapacitive performance than the CNT electrode. The CNC electrode with low internal resistance could deliver a high capacitance of 680 F g −1 at 1 A g −1 in the working potential range of 0.01-3.50 V vs. Li/Li + , which was much better than the commercial CNT electrode (252 F g −1 ). [ABSTRACT FROM AUTHOR]

Abstract: Fine spherical mesocarbon-microbeads (MCMBs), having average particle sizes of 24.57, 11.69 and 10.74μm, were mixed with various amounts of solid-resins (with high β-resin contents) to prepare graphite-matrixes in self-sintering reactions. The results indicate that the self-sintering reactions of the MCMBs can be significantly improved by enhancing the contacting-pattern of the mixture. MCMBs with smaller particle sizes favor self-sintering reactions and can be used to form high-quality graphite-matrixes. In addition, the self-sintering reactions are strongly dependent on the β-resin content of the raw materials. The bending strength of the graphite-matrixes increases, while the density of the graphite-matrixes decreases, with an increase of the β-resin content in the raw materials. The optimum β-resin content in the mixtures needed to obtain high density graphite-matrixes is approximately 5.0wt.%. [Copyright &y& Elsevier]