超细WO_3粉体的制备及表征

Preparation and Characterization of Ultra-Fine WO_3 Powder

通过胶溶法、溶胶 凝胶法、聚合 络合法合成了超细三氧化钨粉体。并对 3种制备方法的不同制备条件进行了探讨 ,实验发现不同制备条件对三氧化钨粉体粒径有较大影响 ,研究得出了每种方法的最佳制备条件。胶溶法中pH约为 4.60 ,静置 2 4h ,加入十六烷基三甲基溴化铵(CTAB)浓度为 0 .15mol·L- 1 ;溶胶 凝胶法中pH约为 2 .3 1,加入草酸和CTAB浓度分别为 0 .40和 0 .2 0mol·L- 1 ;而聚合 络合法中前驱体在 2 5 0℃干燥后 ,在 60 0℃煅烧接着再在 65 0℃煅烧。用激光粒度仪、比表面测定仪、XRD和TEM对产品进行了表征 ,结果表明所制三氧化钨为正交晶系 ,平均粒径在 5 0～ 2 0 0nm。团聚粒子大小不均 ,粒径范围较宽 ,颗粒为不规则形状。胶溶法制备的粒子的粒径较其他两种方法更小、更均匀。

The ultra fine WO 3 powder was prepared by colloidal chemistry method, sol gel and polymerized complex method. The effect of different preparation conditions in three preparation methods was discussed on particle size. The optimum preparation conditions were as follows: controlling pH 4.60, aging 24 h, then adding 0.15 mol·L -1 CTAB in colloidal chemistry method. Controlling pH 2.31, then adding 0.40 mol·L -1 oxalic acid and 0.20 mol·L -1 CTAB in sol gel method. The precursor dried at 250 ℃, then was calcined firstly at 600 ℃ and then 650 ℃ as for polymerized complex method. The WO 3 powder was characterized by laser scattered particle analyzer, specific surface area testing instruments, X ray diffraction and transmission electron microscopy respectively. The characterizations show ultra fine WO 3 powder is orthorhombic and the average particle size is from 50 to 200 nm. The morphological structure is irregular. Compared with other two methods, the particle size prepared by colloidal chemistry method is the smallest.