Mg-Al-NO_3层状双金属氢氧化物电性质研究  

Studies on Electric Property of Mg-Al-Nitrate Layered Double Hydroxide

作　　者：金志琳[1] 侯万国[1] 张春光[1] 孙祉伟[2] 杨亲正[1] 孙德军[1] 戴国亮[2] 

机构地区：[1]山东大学胶体与界面化学教育部重点实验室,济南250100 [2]中国科学院力学研究所国家微重力实验室,北京100080

出　　处：《化学学报》2003年第8期1208-1212,共5页Acta Chimica Sinica

基　　金：国家自然科学基金 (No.2 98730 2 6);教育部跨世纪人才基金资助项目

摘　　要：采用电泳法和电势滴定法测定出不同电解质 (LiCl ,NaCl和KCl)溶液中Mg Al NO3 层状双金属氢氧化物 (Mg Al NO3 LDH)颗粒的 ζ电位、等电点、永久电荷密度以及零电荷点等电化学物理量 ,探讨了电解质、pH和样品化学组成对Mg Al NO3 LDH电性质的影响 .研究发现一价阳离子Li+ ,Na+ ,K+ 对Mg Al NO3 LDH颗粒的等电点有影响 ,使等电点依次降低 ;由于永久电荷的存在 ,等电点与零电荷点不一致 .随着样品中Al含量的增加 ,永久电荷密度依次增加 ,零电荷点依次增大 。Electrochemical parameters of Mg-Al-NO3LDH particles in different electrolytic solutions (LiCl, NaCl and KCl), including zeta potential, isoelectric point (pH(IEP)), permanent charge density (sigma(P)), and zero point of charge (pH(ZPC)) have been measured by electrophoresis method and potentiometric titration. Effects of electrolyte, pH, and chemical composition on electric property of the positive sol were investigated. It has been found that the pHIEP decreases with the sequence of Li+, Na+, K+. Because of the permanent positive charge, the pH(IEP) is not equal to the pH(ZPC). The values of both sigma(P) and pH(ZPC) of Mg-Al-NO3LDH increase with the increase of the contents of Al3+ in the LDH samples, whereas the corresponding pH(IEP) decreases rather than the increase.

关 键 词：Mg-Al-NO3层状双金属氢氧化物 电性质 等电点 零点荷点 永久电荷密度 电势滴定法 

分 类 号：O614[理学—无机化学]