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Two kinds of carbon-support 20% Pd/C catalysts for use in direct ethanol fuel cell (DEFC) have been prepared by an impregnation reduction method using NaBH4and NaH2PO2as reductants, respectively, in this study. The catalysts were characterized by XRD and TEM. The results show that the catalysts had been completely reduced, and the catalysts are spherical and homogeneously dispersed on carbon. The electrocatalytic activity of the catalysts was investigated by electrochemical measurements. The results indicate that the catalysts had an average particle size of 3.3 nm and showed the better catalytic performance, when NaBH4was used as the reducing agent. The electrochemical active surface area of Pd/C (NaBH4) was 56.4 m2·g−1. The electrochemical activity of the Pd/C (NaBH4) was much higher than that of Pd/C (NaH2PO2).

As Carbon-fiber-reinforced SiC-matrix (C/SiC) composites are widely used in high-temperature structural applications, its mechanical behavior at high temperature is important for the reliability of structures. In this paper, mechanical behavior of a kind of 2D C/SiC composite was investigated at temperatures ranging from room temperature (20C) to 600C under quasi-static and dynamic uniaxial compression. The results show the composite has excellent high temperature mechanical properties at the tested temperature range. Catastrophic brittle failure is not observed for the specimens tested at different strain rates. The compressive strength of the composite deceases only 10% at 600C if compared with that at room temperature. It is proposed that the decrease of compressive strength of the 2D C/SiC composite at high temperature is influenced mainly by release of thermal residual stresses in the reinforced carbon fiber and silicon carbon matrix and oxidation of the composite in high temperature atmosphere.

A new approach of spontaneous deposition was carried out to prepare the Ru/Pt film electrocatalyst for direct methanol fuel cells. This deposition method just made Pt like a ‘skin’ covered Ru films, which reduced the load of Pt but obtained a higher activity. The Pt-modified Ru films electrode was studied with the cyclic voltammetries and in-situ ATR-SEITA spectra on methanol oxidation. Compare to bare Ru and Pt, the bands of the adsorbed CO and water observed in IR spectra can be assigned. The present results give a clue for designing new electrocatalysts for DMFCs.

Li-ion batteries have been widely used to power portable electronic equipments, and have been considered as an alternative source of power for electric or hybrid vehicles. Cathode is a key part of Li-ion battery and determines the battery performance. In this paper, we briefly introduced an important and promising Li-Ni-Co-Mn-O cathode with high capacity and working voltage. The development status, modification methods, and existent issues of Li-Ni-Co-Mn-O cathode were also introduced. And in the end, we propose a possible solution to the issues blocking in application processes.