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Enhancement of the heat transfer of the cold side is one of the approaches to improve the performance of thermoelectric generator systems (TEGs). In order to investigate viability and further performance of the TEG for waste heat recovery in industry area, a small low-temperature waste heat thermoelectric generator setup has been constructed with graphene oxide (GO) nanofluids as coolants in the paper. The results showed excellent stability of GO nanofluids through the preparation of two-step method to be applied in the TEGs .The highest open output voltage of TEG system were obtained by 0.15% weight fraction of GO nanofluids as coolant when the temperature difference (△T) was designed at 95K and the hot side temperature was fixed at 373K in the TEGs. Compared with conventional glycol-water base fluid as coolant, the highest open voltage enhancement ratio has reached 65.26% in the TEGs.

Abstract A chemical reduction method for preparing monodispersed pure-phase copper colloids in water and ethylene glycol has been reported. Owing to the reduction property of ethylene glycol, the reaction rate in ethylene glycol is higher than that in water. In addition, the amount of reducing agent can be reduced largely. Ascorbic acid plays roles as reducing agent and antioxidant of colloidal copper, due to its ability to scavenge free radicals and reactive oxygen molecules. Thermogravimetric results reveal that the as-prepared copper nanoparticles have good stability, and they begin to be oxidized at above 210 °C. Polyvinyl pyrrolidone works both as size controller and polymeric capping agents, because it hinders the nuclei from aggregation through the polar groups, which strongly absorb the copper particles on the surface with coordination bonds.

CaCu3Ti4O12 nanowires (CCTO-NWs) with different aspect ratios were synthesized by two-step hydrothermal method. CCTO-NWs/PVDF composites were prepared using CCTO-NWs as filler and polyvinylidene fluoride (PVDF) as matrix. The effects of CCTO-NWs content and its aspect ratio on dielectric properties of composites were investigated. Results showed that aspect ratios of CCTO-NWs were obtained as 11.84, 14.47, 17.11, and 19.74 by controlling the first hydrothermal reaction temperature to be 180 °C, 200 °C, 220 °C, and 240 °C. At 102 Hz, the dielectric constant of 70-wt% CCTO-NWs/PVDF composite can reach 62.94, which is 3.7 times higher than that of 10-wt% CCTO-NWs/PVDF composite (13.47). Adding CCTO-NWs with high aspect ratio into matrix can effectively improve dielectric constant. When CCTO-NWs content is 60-wt%, compared with fillers with an aspect ratio of 11.84, fillers with an aspect ratio of 19.74 can make the dielectric constant of composites increase about 64%. [ABSTRACT FROM AUTHOR]

Li1.2Ni0.13Co0.13Mn0.54O2 (LNCM) is one of the most promising cathode materials owning to its high theoretical discharge-specific capacity, high voltage plateau, and high energy density. In this study, UIO-66 (Zr-based metal organic frameworks) was synthesized and mixed with LNCM particles to form ZrO2-coated LNCM (LNCM@ZrO2) materials via calcination. The structure and morphology of as-prepared LNCM@ZrO2 were studied. The amount of UIO-66 mixed with LNCM has great influences on its electrochemical performances. When the addition of UIO-66 was 10%, LNCM@ZrO2 presented preferable electrochemical properties. The first discharge capacity was 261.5 mAh/g, and the coulombic efficiency was 82.5% under 0.1C rate. The discharge capacity remained 209.3 mAh/g after 50 cycles. Moreover, the LNCM@ZrO2 materials also demonstrated superior rate capability in comparison to uncoated LNCM material. The convenience and inexpensive nature of the ZrO2-coated LNCM material processing and elevated electrochemical performances made LNCM@ZrO2 a good candidate for high-performance cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Thermal characterization becomes challenging as the material size is reduced to micro/nanoscales. Based on scanning probe microscopy (SPM), scanning thermal microscopy (SThM) is able to collect thermophysical characteristics of the microscopic domain with high spatial resolution. Starting from its development history, this review introduces the operation mechanism of the instrument in detail, including working principles, thermal probes, quantitative study, and applications. As the core principle of SThM, the heat transfer mechanism section is discussed emphatically. Additionally, the emerging technologies based on the SThM platform are clearly reviewed and corresponding examples are presented in detail. Finally, the current challenges and future opportunities of SThM are discussed. [ABSTRACT FROM AUTHOR]