Trifluorophenyl‐functionalized multi‐walled‐carbon‐nanotube/poly(vinylidene fluoride) (TFP‐MWNT/PVDF) nanocomposites are fabricated by employing a wet‐chemistry route. The modified MWNTs are observed to form a well‐dispersed, structurally random nanophase within the polymer matrix (see figure). The TFP‐MWNT/PVDF nanocomposite exhibits enhanced dielectric permittivity when the content of TFP‐MWNT is close to the percolation threshold.

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This letter reports the role of nanoparticle surface modification in affecting the space charge distribution of polyethylene/silica nanocomposite dielectrics. Space charge distribution in the nanocomposites was measured using a pulsed electroacoustic method. The results suggested that the nanoparticle surface modification has significant effects on the space charge behaviors in polyethylene and that the nanocomposites with surface-treated silica showed improved space charge distribution, which can be understood in terms of the morphological variation of the matrix and the better interfacial adhesion between the surface-treated nanoparticles and the matrix.

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This paper presented the measurement results of space charge distribution and high field conduction in cross-linked polyethylene (XLPE) plate sample at various electric fields for a broad temperature range from 30 to 90 o C. The temperature effect on charge trapping and transport mechanism is discussed based on estimation of threshold characteristic and apparent mobility. It is shown that the threshold field for space charge accumulation apparently decreased with the temperature, probably associated with acceleration of charge injection and ionic dissociation. The apparent mobility of charges showed an exponential dependence on temperature, which indicates enhancement of charge detrapping and transfer rate at higher temperature. The field dependence of the space charge decreases with the temperature, results in more space charge accumulate at room temperature than at high temperature at certain high field. This behavior indicates that the space charge formation rate increases slower than the charge detrapping rate as the temperature increases. Besides, negative charge is always dominant in the sample at the measuring field and temperature range. This is probably due to stronger electron injection at XLPE-aluminum interface or more negative ion formed by dissociation of chemical species.

Utilizing electricity and heat from renewable energy to convert small molecules into value‐added chemicals through electro/thermal catalytic processes has enormous socioeconomic and environmental benefits. However, the lack of catalysts with high activity, good long‐term stability, and low cost strongly inhibits the practical implementation of these processes. Oxides with exsolved metal nanoparticles have recently been emerging as promising catalysts with outstanding activity and stability for the conversion of small molecules, which provides new possibilities for application of the processes. In this review, it starts with an introduction on the mechanism of exsolution, discussing representative exsolution materials, the impacts of intrinsic material properties and external environmental conditions on the exsolution behavior, and the driving forces for exsolution. The performances of exsolution materials in various reactions, such as alkane reforming reaction, carbon monoxide oxidation, carbon dioxide utilization, high temperature steam electrolysis, and low temperature electrocatalysis, are then summarized. Finally, the challenges and future perspectives for the development of exsolution materials as high‐performance catalysts are discussed.

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In this study, we investigated the influence of the surface treatment of Al nanoparticles on the electrical properties of linear low density polyethylene composites. Octyl-trimethoxysilane was used as a nonpolar silane coupling agent for the surface treatment of Al nanoparticles. It was found that the incorporation of nonpolar octyl groups onto the surface of Al nanoparticles not only increased the percolation threshold and the resistivity but also improved the dielectric properties as compared to the composites filled with unsurface-treated nanoparticles. The surface treatment makes it possible to easily control the frequency and concentration dependences of dielectric constant and provided an excellent approach able to considerably reduce the dielectric loss of the nanocomposites, which is of great significance from the viewpoint of practical application of the polymer/metal nanocomposites in the electrical and electronic industries. It is concluded that the improved electrical properties could be directly ascribed to the good dispersion and special electrical feature of the surface-treated nanoparticles in the polymer matrix.