Cerium monosulfide (CeS) powder was synthesized by the reduction of Ce 2 S 3 powder with metallic Ce, which was obtained from ceria (CeO 2 ) powder using carbon disulfide (CS 2 ) gas. To obtain the maximum amount of CeS from a mixture of Ce 2 S, and Ce, an excess amount of metallic Ce, a stoichiometric composition, was necessary in the synthesis at 1273 K for 10.8 ks. The preliminary sintering experiments also were performed using a synthetic CeS powder containing a small amount of Ce, Ce 2 O 2 S, and β-Ce 2 S 3 as impurities. It was found that the oxygen content in the sintered compact decreases gradually as the sintering temperature increases, because of the removal of the impurities due to the evaporation of the volatile CeO. Single-phase CeS was formed by sintering at 2173 K. To evaluate the activation energy for densification of single-phase CeS, a CeS powder was prepared by milling an initial sintered compact and was used as an ingredient for hot-press experiments. Densification data during hot-press sintering were analyzed using a kinetic equation, showing that boundary diffusion is a rate-limiting process. The results suggest that this boundary diffusion model can explain well the densification data, with an apparent activation energy of 479 kJ.mol -1 .

中文翻译：

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一硫化二铈的合成与烧结

通过使用二硫化碳 (CS 2 ) 气体从二氧化铈 (CeO 2 ) 粉末中获得金属 Ce，通过将 Ce 2 S 3 粉末还原合成一硫化铈 (CeS) 粉末。为了从 Ce 2 S 和 Ce 的混合物中获得最大量的 CeS，在 1273 K 合成 10.8 ks 时需要过量的金属 Ce，化学计量组成。还使用含有少量Ce、Ce 2 O 2 S和β-Ce 2 S 3 作为杂质的合成CeS粉末进行初步烧结实验。发现随着烧结温度的升高，烧结体中的氧含量逐渐降低，这是由于挥发性CeO的蒸发去除了杂质。通过在 2173 K 下烧结形成单相 CeS。为了评估单相 CeS 致密化的活化能，通过研磨初始烧结体制备 CeS 粉末，并将其用作热压实验的成分。使用动力学方程分析了热压烧结过程中的致密化数据，表明边界扩散是一个限速过程。结果表明，该边界扩散模型可以很好地解释致密化数据，表观活化能为479 kJ.mol -1 。