表面活性剂对共沉淀法制备ZAO纳米粉的影响

Influence of Surfactant on ZAO Nano-Powder Prepared by Coprecipitation Method

ZAO(ZnO/Al2O3复合氧化物)结合了纳米材料和半导体氧化物的优越性能,但随着粉体粒径的减小,粉体极易发生团聚.为解决纳米粉体的团聚现象,采用"共沉淀-超临界流体干燥"结合法,加入几种不同的表面活性剂制备了ZAO超细纳米粉.实验通过X射线衍射对ZAO粉末物相进行分析.TEM观察粒子的形貌、粒径大小及其团聚状态,分析了几种表面活性剂的种类及用量对粉末特性的影响.该方法有效地解决了粉体的团聚现象.研究结果表明:采用"共沉淀-超临界流体干燥"技术,加入表面活性剂PEG-400,且其与Zn2+离子的物质的量比为1∶16时,制备的ZAO粒子的平均粒度小于10nm,粉体粒径均匀,分散性好,团聚现象不明显.

ZAO（Aluminum-doped zinc oxide） shows excellent properties which relates nano-materials and oxide semiconductor. But the nano-powder forms aggregation easily with the decrease of powder size. To solve this problem,＂coprecipitation/supercritical fluid drying（SCFD）＂ is investigated. Adding in different surfactant during the process of coprecipitation supercritical fluid drying, ZAO nanopowders are synthesized. XRD is employed for the analysis of phase. TEM is used to characterize the morphology, grain size and agglomeration state of ZAO powders. The effect of species and dosage of surfactant, dosage of transition liquid on the properties of nano-powder was reviewed. Results show. When the molar ratio of surfactant PEG-400 and Zn2＋ ion is 1： 16,ZAO powders are obtained with size smaller than 10 nm. Particle distribution shows that there no significant aggregation in ZAO powder.