影响纳米CeO_2晶粒形貌的因素及机理

以Ce(NO3)3.6H2O为铈源,NH3.H2O为沉淀剂,用普通沉淀法在不同反应条件下制备了粒径、形貌各异的纳米CeO2。研究结果表明,Ce(NO3)3最佳浓度为0.2 mol/L。XRD和IR结果证实了产物的物相结构。TEM分析表明:控制pH可以得到形貌不同的纳米CeO2粒子。用乙醇作溶剂得到了粒径约为15 nm、分布均匀的纳米CeO2颗粒。正加料(沉淀剂滴入盐溶液中)可以得到各种形貌的纳米CeO2;而反加料(盐溶液滴入沉淀剂中)仅能得到针状纳米CeO2颗粒。

Factors and Mechanisms Influencing the Morphology of CeO2 Nanoparticle

Nanocrystalline CeO_2 of different sizes and morphologies was prepared by precipitation method using cerium(Ⅲ) nitrate as the raw material and ammonium hydroxide as the precipitant in different reaction conditions.By means of TEM measurements,the morphology and particle size were characterized.CeO_2 nanoparticles of different morphologies were obtained by controlling the pH of solution.Using ethanol as solvent,rather uniform nanoparticles can be obtained.CeO_2 nanoparticles of different morphologies can be obtained by dropping the precipitant into the salt solution,while only needle like nanoparticle can be got when the salt solution is dropped into the precipitant.