Preparation and properties of Ce0.8Ca0.2O1.8 anode material by glycine-nitrate process
(1. Faculty of Materials and Metallurgical Engineering,
Kunming University of Science and Technology, Kunming 650093, China;
2. National Engineering Laboratory of Vacuum Metallurgy,
Kunming University of Science and Technology, Kunming 650093, China)
Kunming University of Science and Technology, Kunming 650093, China;
2. National Engineering Laboratory of Vacuum Metallurgy,
Kunming University of Science and Technology, Kunming 650093, China)
Abstract: Ce0.8Ca0.2O1.8 (CDC82) anode material was prepared by glycine-nitrate process(GNP). Thermogravimetric(TG) analysis and differential scanning calorimetric(DSC) methods were adopted to characterize the reaction process of CDC82 material. X-ray diffractometry(XRD), scanning electron microcopy(SEM), direct current four probe (four-probe DC) and temperature process reduce(TPR) techniques were adopted to characterize the properties of CDC82 material. After the precursor was sintered at 750 ℃ for 4 h, CDC82 material with pure-fluorite structure and nanometer size was obtained. The total conductivity of CDC82 changes little with temperature in air at 50−850 ℃, and the maximum value is 0.04 S/cm at 750 ℃. The total conductivity wholly becomes larger when the atmosphere changes from air to hydrogen, which greatly increases with increasing temperature and reaches the maximum value of 1.09 S/cm at 850 ℃. Some impurities such as CeMg and La2O3 exist after the mixture of CDC82 anode and La1−xSrxGa1−yMgyO3−δ (LSGM) electrolyte material is sintered at 1 200 ℃ for 15 h. The CDC82 material as anode material has excellent catalytic property for hydrogen and methane.
Key words: Ce0.8Ca0.2O1.8; anode material; glycine-nitrate process; conductivity; chemical compatibility; catalytic property