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Abstract: Cerium oxide is a promising material for electrodes and electrolytes of solid oxide fuel cells (SOFCs). Lowering the sintering temperature of the electrolyte will bring a lot of benefits to the fabrication of SOFCs. This paper evaluates the feasibility of using lithium oxide as a sintering aid to reduce the densification temperature of samarium-doped ceria (Ce0.8Sm0.2O1.9, SDC) by SEM and electrochemical impedance spectroscopy. It is shown that the addition of Li2CO3 can indeed decrease the sintering temperature of SDC. More attention is paid to understand the aiding mechanism of Li2CO3. Raman spectroscopy and thermal analysis indicate that it is Li2O, a decomposition product of Li2CO3, that facilitates the sintering by way of a liquid phase sintering effect on the grain boundaries of SDC. These findings help to promote the application of ceria-based electrolytes for intermediate temperature SOFCs. [Copyright &y& Elsevier]

Abstract: Catalysts of nano-sized nickel oxide particles based on flowerlike lanthanum oxide microspheres with high disperse were prepared to achieve simultaneous dehydrogenation of ethanol and water molecules on multi-active sites. XRD, SEM, 77K N2 adsorption were used to analyze and observe the catalysts’ structure, morphology and porosity. Catalytic parameters with respect to yield of H2, activity, selectivity towards gaseous products and stability with time-on-stream and time-on-off-stream were all determined. This special morphology NiO/La2O3 catalyst represented more than 1000 h time-on-stream stability test and 500 h time-on-off-stream stability test for hydrogen fuel production from ethanol steam reforming at 300 °C without any deactivation. During the 1000 h time-on-stream stability test, ethanol–water mixtures could be converted into H2, CO, and CH4 with average selectivity values of 57.0, 20.1, 19.6 and little CO2 of 3.2 mol%, respectively, and average ethanol conversion values of 96.7 mol%, with H2 yield of 1.61 mol H2/mol C2H5OH. During the 500 h time-on-off-stream stability test, ethanol–water mixtures could be converted into H2, CO, CH4 and CO2 with average selectivity values of 65.1, 17.3, 15.1 and 2.5 mol%, respectively, and average ethanol conversion values of 80.0 mol%. For the ethanol-H2 and petrolic hybrid vehicle (EH–HV), the combustion value is the most important factor. So, it was very suitable for the EH–HV application that the low temperature ethanol steam reforming products’ distribution was with high H2, CO, CH4 and very low CO2 selectivity over the special NiO/La2O3 flowerlike microspheres. [ABSTRACT FROM AUTHOR]