Isotope Effects of Hydrogen Ion Transport in SrCeO_3(+Y_2O_3) and its Applications

对氢在固体电解质SrCe_ Yb_ O_中传输的同位素效应进行了研究<0.95><0.05><3-6>，得到了以下结果。1.在电导率的测量中，在质子传导占主导地位的条件下观察到同位素效应。质子与氘的电导率之比为ROO<2>，这是由经典动力学理论估计的正态差.氢的溶解度用Sieverts法测定。发现该值与其他氧化物相比非常大。氢溶解度的同位素效应未被检测到.从溶解度测量获得化学扩散系数。同位素效应也未检测到。认为氧离子空位的双极扩散机制降低了这种效应.通过热脱附分析，发现了在低氧化学势条件下氢的溶解机理.研究了氢在电解前后试样薄壁中的渗透情况，并基于缺陷模型对其现象进行了分析。未电解时，渗透的轻氢与重氢之比为1.9，电解时为3.5。这些大的同位素效应不能从迁移率的差异来解释。认为电极反应速度的差异是造成这些现象的原因，并由此确定了该电解质作为氢同位素分离膜材料的可能性。

A research on the isotope effects in transport of hydrogen through the solid electrolyte SrCe_<0.95>Yb_<0.05>O_<3-6> was performed and the following results were obtained.1. On the measurement of electrical conductivity, an isotope effect was observed in the conditions where the proton conduction is dominant. The ratio of conductivity of proton to deuteron was ROO<2> which is normal difference estimated from the theory of classical kinetics.2. The solubility of hydrogen was measured by Sieverts method. The value was found very large compared to other oxides. The isotope effect in the solubility of hydrogen was not detected.3. The chemical diffusion coefficient was obtained from the solubility measurements. The isotope effect was also not detected. It was considered that the effect was reduced by the mechanism of ambipolar diffusion with oxygen ion vacancy.4. A new mechanism of solution of hydrogen was found in the condition of low oxygen chemical potential with the measurements of thermal desorption analysis.5. The permeation of hydrogen through the thin wall of the sample with and without electrolysis was studied and its phenomena was analyzed based on the model of defects. The ratio of permeated light hydrogen to heavy one was found 1.9 without electrolysis and was found 3.5 with electrolysis. These large isotope effects are not explained from the difference of their mobilities. The difference of the speed of electrode reaction was suggested as the reason of these phenomena.The possibility of this electrolyte as the material of membrane for the separation of isotope of hydrogen was ascertained from above results.