摘要
以钨粉为原料,H2O2氧化金属钨粉生成的过氧聚钨酸为前驱体,采用水热法制备了WO3及其水合物。低于180℃水热反应12h,得到正交晶型的WO3·0.33H2O和单斜WO3;在180℃水热反应24和45h则生成单斜WO3和六方WO3。结果表明,一定的水热反应温度和时间对晶化是必须的,本实验180℃水热反应24和45h后干燥均得到不含水合物的WO3粉体。水热反应温度的升高和时间的延长均有利于正交WO3·0.33H2O向六方WO3和单斜WO3转化。所制得的纯WO3粉体晶形良好,晶粒尺寸达到了纳米级,并探讨了其水热机制。
Tungsten trioxide and its hydrates were synthesized by hydrothermal method, peroxotungstic acid as precursor, which using a route based on the dissolution of tungsten metal powder in an excess of hydrogen peroxide solution (30%). Orthogonal WO_3·0.33H_2O and monoclinic WO_3 were yielded by hydrothermal method at ≤180 ℃ for 12 h, while monoclinic WO_3 and hexagonal WO_3 yielded at 180 ℃ for 24 h or 45 h. It seems that certain temperature and time are necessary to a high degree of crystallization-tungsten trioxide is completely yielded by hydrothermal method at 180 ℃ for 24 h or 45 h. High temperature and long time are benefit for orthogonal WO_3·0.33H_2O transforming to hexagonal WO_3 and monoclinic WO_3. WO_3 powder is of high degree of crystallization and nano-sized range. A possible crystallization mechanism is proposed.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2005年第3期377-380,共4页
Chinese Journal of Rare Metals
基金
江西省自然科学基金项目(0320030)
省教育厅资助项目(Z02290)
关键词
H2O2氧化
水热结晶
纳米
WO3
hydrogen peroxide oxidation
hydrothermal crystallization
nano-sized
tungsten trioxide
