TPR-TPD-TPO studies on CGO/NiO and CGO/CuO ceramics obtained from freeze-dried precursors
TPR-TPD-TPO studies on CGO/NiO and CGO/CuO ceramics obtained from freeze-dried precursors
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DOI：
10.1016/j.ceramint.2014.06.132
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发表时间：
2014-11
影响因子：
5.2
通讯作者：
J. Marrero-Jerez;A. Murugan;I. Metcalfe;P. Núñez
中科院分区：
文献类型：
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作者：
J. Marrero-Jerez;A. Murugan;I. Metcalfe;P. Núñez
通过冷冻干燥前驱体法在非常低的温度（400 °C）下获得了Ce0.99Gd0.01O2−δ纳米晶粉末。然后，将Ni或Cu硝酸盐的乙醇溶液通过初湿含浸法添加到氧化钆掺杂的氧化铈（CGO）中，然后在空气中于650 °C煅烧，以获得CGO/NiO和CGO/CuO系列SOFC阳极材料。采用X射线衍射、N2吸附-脱附（BET）、程序升温还原（TPR）、程序升温脱附（TPD）和程序升温氧化（TPO）等技术对材料进行了表征。TPR表现出广泛的重叠峰，这是与不同的还原阶段，首先高度分散的金属氧化物物种的还原发生，然后金属氧化物本体还原过程。在还原CGO-金属粉末之后，不再存在金属氧化物（如Ni或Cu的存在所指示的），并且萤石CGO固溶体保持稳定。He-TPD测试表明，CGO/NiO系列催化剂在材料表面吸附了CO物种，而CGO/CuO没有。O2-TPO分析表明，C沉积发生在CO-TPR的CGO/NiO样品，但这并没有发生CGO/CuO系列。
Nanocrystalline powders of Ce0.99Gd0.01O2−δhave been obtained at a very low temperature (400 °C) by a freeze-drying precursor method. Afterwards, ethanol solution of Ni or Cu nitrates were added to gadolinia doped ceria (CGO) by incipient wetness impregnation and then calcined in air at 650 °C in order to obtain CGO/NiO and CGO/CuO series of SOFC anode materials. The resulting materials were characterized by X-ray Diffraction, N2adsorption–desorption (BET), Temperature Programmed Reduction (TPR), Temperature Programmed Desorption (TPD) and Temperature Programmed Oxidation (TPO) techniques. TPR showed wide overlapped peaks which are associated to the different reduction stages; firstly the reduction of highly dispersed metal oxide species took place and then the metal oxide bulk reduction process. After reduction of the CGO-metal powders, the metallic oxides were no longer present (as indicated by the presence of Ni or Cu), and the fluorite CGO solid solution remained stable. He-TPD tests showed that the series CGO/NiO adsorbed CO species on the material surface while CGO/CuO did not. O2-TPO analysis showed that C deposition occurred during the CO-TPR on CGO/NiO samples but this did not occur for the CGO/CuO series.