Fundamental and Applied Study on Hydrogen Gas Production Utilizing Metal-Chalcogen Melts as an Electrode

利用Sn-40at进行了制氢研究。熔体中饱和溶解度相对较大。一种电化学电池：空气、Pt/ZrO_2(+CaO)/O在Sn-40at中。熔体被构建。氩气通过水（0 C），在1123 K时对电池(I)施加电压(V)，开始生产实验。在确定稳定的电流(I)后，将水的温度改变为另一个温度（30,50或70 C），并研究电流对水温的依赖关系。对于生产效率高的电极，依赖度应较大；用多孔铂或纯锡熔体代替Sn- te熔体进行了类似的实验，并进行了比较。对于纯锡熔体，电流对水温的依赖性最大，Sn- te熔体和铂熔体的效率相当。结果表明，氧的饱和溶解度并不是最重要的影响因素。虽然与预期不同，但氧化速率和随后的脱氧是最重要的。对于锡熔体电极，由于界面张力的差异，在熔体表面形成的SnO_2会迅速向熔体-氧化锆界面移动。目前的结果表明，锡熔体的性能远远优于用于常规制氢的多孔Pt。将锡等熔体与氧化物粉末电极混合是一种极具吸引力的方法，可以使电极具有更高的效率。

Study on the hydrogen production was performed utilizing Sn-40at.%Te Melt in which the saturation solubility is relatively large. An electrochemical cell:Air, Pt/ZrO_2(+CaO)/O in Sn-40at.%Te melt was constructed. Argon gas was passed through water(0 ﾟC), and the production experiment was started at 1123 K by applying a voltage(V) to the cell(I). After confirming a steady electric current(I), the temperature of the water was changed to another one(30, 50 or 70 ﾟC), and the dependence of the current on the water temperature was investigated. For an electrode with high production efficiency, the dependence should be larger; similar experiments with porous platinum or pure Sn melt instead of the Sn-Te melt were also performed and compared. For pure Sn Melt, the dependence of the current on the water temperature is largest, and the efficiencies with the Sn-Te melt and platinum were comparable. This results indicate that the saturation solubility of oxygen is not the most important factor. Although differing from expectation, the rate of oxidation and the following deoxidation is most important. For the Sn melt electrode, SnO_2 formed on the above surface of the melt may move promptly toward the interface of the melt-zirconia interface due to the difference of interfacial tension. The present result, that is, the property of Sn melt is far excellent than that of porous Pt which is used for conventional hydrogen production. Mixing the melts such as Sn with oxide powder electrode, which seems one of the attractive candidates may lead to the electrode having far high efficiency.