固体氧化物燃料电池(SOFC)阳极材料得失电子能力和氧扩散性能影响其催化性能。对 NiO 体积含量分别为20%和40%的 NiO/La2 Mo2 O9复合材料(N/L28和 N/L46)的介电行为以及得失电子能力进行了研究。N/L28和 N/L46样品的介电温度谱中按照损耗峰出现的温度从低到高的顺序依次发现与NiO 相和 La2 Mo2 O9相氧短程扩散有关的损耗峰,833K 处观察到的介电损耗的突变与αLa2 Mo2 O9-βLa2Mo2O9相变有关。N/L46样品在500~813K 范围内的一个宽化的损耗峰可用一个具有弛豫性质的峰和两个非弛豫性质的峰进行拟合。表面势测量结果表明,样品失去电子所需能量由大到小的顺序为La2 Mo2 O9,N/L28,N/L46,NiO。%The electron gain and loss capability and oxygen diffusion behavior of SOFC anode materials have effects on their catalytic property.In this paper,dielectric behavior and the capability of electron gain and loss for NiO/La2 Mo2 O9 composite with 20% and 40% NiO in volume (abbreviated as N/L28 and N/L46,respec-tively)were studied.According to the order from low to high temperature,the dielectric loss peaks associated with NiO phase and short distance diffusion of oxygen vacancies in La2 Mo2 O9 phase were observed respectively in both N/L28 and N/L46 samples.The stepwise change of dielectric loss at 833K in both N/L28 and N/L46 samples were attributed to theαLa2 Mo2 O9-βLa2 Mo2 O9 phase transition.For N/L46 sample,a broadened die-lectric loss peak observed in 500-813K can be fitted by one relaxation peak and two non-relaxation peaks.The results of surface potential measurement using Kelvin probe method indicate that the energy descending order for electron loss was La2 Mo2 O9 ,N/L28,N/L46,NiO.
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