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用具有加热台的扫描电镜对氧化钨氢还原产物的形貌作了动态观察,在同一试样上观察到产物在不同还原阶段时形貌的连续变化。由APT·5H_2O得到的三氧化钨在700℃氢还原中,氧化钨颗粒逐渐变小,表面逐渐变粗,形貌变化不十分明显。900℃氢还原APT·5H_2O的真空热解产物,最初得到了少量定向排列的WO_(2.72)晶须和大量杂乱排列的WO_(2.72)柱状晶。前者可能是气相输送反应的结果,后者可能是气固反应的产物。APT·5H_2O热分解产物在900℃还原时形貌变化明显;而APT·11H_2O热分解产物在相同条件下还原时,形貌变化平缓,钨粉的一次晶粒度较前者细。
The morphology of the hydrogen reduction product of tungsten oxide was observed by scanning electron microscope (SEM) with heating stage. The continuous change of the morphology of the product during different reduction stages was observed on the same sample. Tungsten oxide obtained from APT · 5H 2 O at 700 ℃ hydrogen reduction, tungsten oxide particles gradually become smaller, the surface becomes thicker, the morphology is not very obvious. The vacuum pyrolysis products of APT · 5H_2O were hydrogenated at 900 ℃. A small amount of oriented WO_ (2.72) whiskers and a large number of disordered WO_ (2.72) columnar crystals were obtained. The former may be the result of the vapor phase transport reaction, which may be the product of the gas-solid reaction. The thermal decomposition products of APT · 5H_2O showed obvious morphological changes at 900 ℃, while the thermal decomposition products of APT · 11H_2O reduced gently under the same conditions.