千层饼状Cd(OH)_2微米结构的合成与表征

Synthesis and Characterization of Doughnuts Like Cd(OH)_2 Microstructure

以羰基修饰的聚丙烯酰胺(缩写为PAM-COOH)作为形貌控制剂,采用水相法合成了千层饼状Cd(OH)_2微米结构.产物结构与形貌用X射线衍射仪(XRD),扫描电子显微镜(SEM)、透射电子显微镜(TEM)和选区电子衍射仪(SAED)进行了表征.研究了不同实验条件(PAM-COOH的浓度、反应物浓度、反应温度和反应时间等)对产物形貌与尺寸的影响.讨论了PAM-COOH作用下Cd(OH)_2千层饼可能的形成机理.结果表明,Cd(OH)_2千层饼尺寸约1μm,每个千层饼由尺寸约为35nm的Cd(OH)_2单晶薄片组成.反应物浓度、反应温度对Cd(OH)_2尺寸与形貌都有一定的影响,但起关键作用的是PAM-COOH.在350℃煅烧Cd(OH)_2 3h,得到立方结构千层饼状CdO微米材料.

Doughnuts like Cd（OH）2 microstructures were synthesized by aqueous-phase method using carboxyl functionalized polyacrylamide （PAM-COOH） as crystal growth modifiers, which were characterized by X-ray powder diffraction （XRD）, scanning electron microscope （SEM）, transmission electron microscope （TEM） and the selected area electron diffraction （SAED）. The influence of experimental conditions such as concentration of surfactant and reactants, temperature and reaction time on the structure and morphology of as-products were carried out in detail. Furthermore, possible formation mechanism of Cd（OH）2 doughnuts in the presence of PAM-COOH was discussed. Results show that the obtained Cd（OH）2 doughnuts with size of 1um is composed of many single-crystal thin flakes with size of about 35nm. The temperature and concentration of reactants have effect on the morphology and size of the obtained product, but PAM-COOH plays a key role in the formation of Cd（OH）2 doughnuts. Cubic phase CdO with doughnuts structure can be obtained by calcination of Cd（OH）2 doughnuts at 350℃ for 3h.