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An analytical model is developed for the effective thermal conductivity of the composites with graphene nanoplates (GNPs) within the framework of differential-effective-medium (DEM) theory. Results of the present model are compared to an effective-medium-approximation (EMA) based model and available experimental results. Predictions on the effective thermal conductivity of GNP/PA-6 and GNP/epoxy composites are in good agreement with the experimental data. Moreover, the present model can well describe the large thermal conductivity enhancement in GNP composites and, in particular, the nonlinear dependence of effective thermal conductivity on the volume fractions of GNPs, which is superior to the EMA model.

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A cobalt triphenylcorrole (CorCo) was covalently bonded to graphene oxide (GO), and the resulting product, represented as GO-CorCo, was characterized by UV-vis, FT-IR, and micro-Raman spectroscopy as well as by HRTEM, TGA, XRD, XPS, and AFM. The electrocatalytic activity of GO-CorCo toward the oxygen reduction reaction (ORR) was then examined in air-saturated 0.1 M KOH and 0.5 M HSO solutions by cyclic voltammetry and linear sweep voltammetry using a rotating disk electrode and/or a rotating ring-disk electrode. An overall 4-electron reduction of O is obtained in alkaline media while under acidic conditions a 2-electron process is seen. The ORR results thus indicate that covalently bonded GO-CoCor can be used as a selective catalyst for either the 2- or 4-electron reduction of oxygen, the prevailing reaction depending upon the acidity of the solution.

In this paper, a facile approach for the synthesis of stimuli-responsive fluorescent elastomer was developed. The photoluminescence should partly be attributed to the hampered intramolecular rotation of the aryl rotors of the dye molecules by wrapping and coiling of the flexible polymer chains. In addition, the reversibility of this responsiveness was also confirmed.