（最后一份、三四章结合的）陶瓷粉体制备.pptVIP

结构陶瓷制备工艺;关键: 高纯、超细、组分均匀分布和无团聚的粉体; 纳米材料是纳米科技的基础，而纳米粒子的制备及其表征工作是纳米材料研究领域中的最基本、最重要的研究工作。目前，纳米粒子的制备方法很多，根据不同的分类标准，可以有多种分类方法。根据反应环境可分为液相法、气相法和固相法；根据反应性质可分为化学制备法、化学物理制备法和物理制备法。不同的制备方法可导致纳米粒子的性能以及粒径各不相同。 ;　　液相法(Solution-based method)制备纳米微粒是将均相溶液通过各种途径使溶质和溶剂分离，溶质形成一定形状和大小的颗粒，得到所需粉末的前驱体，热解后得到纳米微粒。 　　液相法具有设备简单、原料容易获得、纯度高、均匀性好、化学组成控制准确等优点，主要用于氧化物系超微粉的制备。;1　化学沉淀法;（1）共沉淀法 　　通过化学反应将溶液中的金属离子共 沉下来。先将金属盐类按比例配好，在溶液 均匀混合，再用强碱作沉淀剂，将多种金属离子共同沉淀下来。;Fabrication and Characterization of BaCO3 Nanostructures;;TEM micrographs of the samples prepared using NaHCO3 as the CO32– source for different time:(a-c) 30 min; (a) A typical TEM micrograph; (b) an individual nanorod and the corresponding SAED pattern of the individual nanorod before and after exposure to electron beam irradiation, respectively;(c) the rod assembled from nanoparticlesand the corresponding SAED pattern. (d-h) 30 s.;TEM micrographs of the sample prepared using Na2CO3 as the CO32– source. (a) A typical TEM micrograph; (b) an individual nanorod and the corresponding SAED pattern. (c) the rod and the corresponding SAED pattern taken after exposure to electron beam irradiation.;SEM micrographs of the sample prepared using (NH4)2CO3 as the CO32– source. (a) A typical SEM micrograph; (b) an individual flower-like structure.;Synthesis of Needle-like and Flower-like Zinc Oxide by a Simple Surfactant-free Solution Method;In a typical experimental procedure,Zn(CH3COO)2·2H2O or Zn(NO3)2·6H2O was dissolved in deionized water to form 0.13M solution. Excess NaOH was dissolved in the above solution at room temperature　by a magnetic stirrer ([NaOH] = 1.3 M). A white precipitate occurred immediately but it was dissolved by further stirring. The above solution was heated by an oil bath at appropriate temperature for a certain time. Then the heating was terminated and the solution was allowed to cool to room temperature. The products were separated by centrifugation, washed with absolute ethanol three times, and dried