酸蒸气水热免洗法制备前驱物ZrMo2-xWxO7(OH,Cl)2·2H2O和立方ZrMo2-xWxO8热收缩化合物

采用酸蒸气水热免洗方法合成了立方ZrW2O8类型化合物的系列前驱物ZrMo2-xWxO7(OH, Cl)2·2H2O(x=0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8), 并由此制备了纯立方相ZrMo2-xWxO8(x=0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8). 提出了用X射线粉末衍射相对积分强度表征有序-无序介稳态晶体有序度的方法, 发现在制备条件下, 随着Mo/W摩尔比的减小, 立方相ZrMo2-xWxO8有序-无序介稳态的饱和有序度增加的规律. 讨论了原料选择以及中间产物的形貌对合成目标产物的影响, 探讨了以铵盐为原料制备前驱物反应的微观过程.

Synthesis of Precursors ZrMo2-xWxO7(OH,Cl)2·2H2O and Cubic ZrMo2-xWxO8 Thermal Contraction Compounds by Acidic Steam Hydrothermal No-wash Method

The precursors, ZrW2O7(OH,Cl)2·2H2O(x=0 ,0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8), of cubic ZrMo2-xWxO8 were synthesized successfully by acidic steam hydrothermal no-wash(ASH-NW) method, in succession the preparation of cubic ZrMo2-xWxO8 were made from the precursors. The relative XRD intensity was proposed to characterize the saturated order degree(η'T) of the metastable order-disorder phases and the correlation was found that the n(Mo)/n(W) ratio is reduced, the order degree(η'T) is risen under the preparation condition. An argumentation was presented to discuss the effect of raw materials on the morphology of the intermediate phase as well as the products. Furthermore, the outline of the micro-process in which the ammonium salt was used as the raw material during the preparation of precursor was discussed.