高岭石—纳米银复合物的制备与表征

采用萍乡硬质高岭土作原料,以高岭石-二甲基亚砜(Kao-DMSO)插层复合物为前驱体,采用置换取代法制备高岭石-甲醇(Kao-MeOH),通过吸附后还原生长,从而成功制备高岭石-纳米银复合物.并采用X射线衍射和透射电镜对高岭石-纳米银复合物进行了表征,主要研究了最佳混合物配比、最佳硝酸银浓度、硼氢化钠浓度对制备高岭石-纳米银复合物的影响.实验结果表明:高岭石层间的纳米银粒子粒径大小均匀且粒径分布范围窄,呈圆形;高岭石片层表面或端面处的纳米银粒子粒径粗大,形状不规则,常有纳米颗粒团聚现象.对生成的纳米银的粒径影响程度从大到小的顺序为:硝酸银与Kao-DMSO的配比、还原反应时硼氢化钠溶液的初始浓度、还原反应时硝酸银溶液的浓度.硝酸银或硼氢化钠的浓度越大,所得纳米银粒子的粒径越大;要得到粒径较小、粒径分布比较集中的样品,应控制硝酸银的浓度为1×10-3～5×10-3 mol/L、硼氢化钠的浓度1×10-2 mol/L,配比为高岭土中Ag的含量占0. 5%～1%.

Preparation and Characterization of Kaolinite-Nano Silver Compound

Kao-Dimethyl Sulfoxide Intercalation(DMSO) compound was prepared by the Pingxiang hard kaolin as the precursor,and Kao-carbinol compound was prepared by the replacement substitution way,then kaolinite-nanometer silver compound was prepared by having been soaked and deoxidized.Kaolinite-nano silver compound were characterized by X-ray diffraction and transmission electron microscopy.The authors study effects of the optimum allocated proportions,the best silver nitrate concentration,sodium borohydride concent...