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Thermal interface materials (TIMs) with high through-plane thermal conductivity are urgently desired to avoid overheating of high-power density electronics. Introducing and aligning fillers in polymer matrixes via magnetic field is a promising method to improve the thermal conductivity of the polymer. However, either the fillers need to be modified with magnetic particles or a strong magnetic field is needed for good alignment in high filler content. This prevents further improvement of the through-plane thermal conductivity. Herein, mesophase pitch-based carbon fibers (MPCFs) with a content as high as 76 wt.% are aligned vertically in water-soluble polyvinyl alcohol (PVA) under a low magnetic field (∼ 0.4 T), forming a vertically aligned MPCF (VAMPCF)/PVA composite with an extraordinary through-plane thermal conductivity of 86 W/(m·K), which is higher than that of many alloys. In addition, both theoretical and experimental results demonstrate that the critical intensity of the magnetic field needed for good alignment of the fillers depends on their size and magnetic susceptibility. Furthermore, the water solubility of PVA makes it easy to recycle MPCFs. This study offers an inspired venue to develop excellent and eco-friendly TIMs to meet ever increasing demand in heat dissipation for electronics. [ABSTRACT FROM AUTHOR]

Decane is one of the volatile organic compounds (VOCs) in human breath. Successful detection of decane in human breath has vast prospects for early lung cancer diagnosis. In this paper, a novel detecting device based on a filter surface acoustic wave (SAW) gas sensor is presented. SAW sensors coated with a thin oxidized graphene film were used to detect decane in parts per million (ppm) concentrations. Control and signal detection circuits were designed using a vector network analyzer with a detection resolution of insertion loss down to 0.0001 dB. The results showed that the SAW sensor could respond quickly with great sensitivity when exposed to 0.2 ppm decane. This device shows tremendous potential in medical diagnosis and environmental assessment. [ABSTRACT FROM AUTHOR]

A so called all-carbon based graphene field effect transistor (GFET) in which the electrodes are composed of graphite-like nano-sheets instead of metals in the traditional devices is fabricated by one-step e-beam direct writing (EBDW). It is also found that the graphite-like nano-sheets in electrodes are perpendicular to the channel graphene, which is confirmed by the transmission electron microscopy (HRTEM). The one-step fabrication of the carbonaceous electrodes is more convenient and lower-cost comparing to the preparation of traditional metal electrodes and can be applied to many other nano-electronic devices. [ABSTRACT FROM AUTHOR]