Experimental study on dielectric relaxation of SiO2 nano-particle suspensions for developing a particle characterization method based on electrical impedance spectroscopy
Experimental study on dielectric relaxation of SiO2 nano-particle suspensions for developing a particle characterization method based on electrical impedance spectroscopy
复制标题
SiO2 纳米颗粒悬浮液介电弛豫的实验研究，用于开发基于电阻抗光谱的颗粒表征方法
DOI：
10.1016/j.powtec.2015.04.070
复制
发表时间：
2015-09
影响因子：
5.2
通讯作者：
M Wang
中科院分区：
文献类型：
--
作者：
Y L Zhao;M Wang
本文采用电阻抗谱方法研究了SiO2纳米颗粒悬浮液的介电弛豫特性。研究了由厚双电层颗粒组成的悬浮液的情况。本研究的目的是找出颗粒的性质（尺寸和浓度）和电阻抗谱之间的关系，开发一种基于电阻抗谱/断层成像的颗粒表征方法。研究和分析了颗粒尺寸对电阻抗谱和弛豫频率的影响。实验结果表明，阻抗相位角和α弛豫频率是颗粒尺寸的函数，α弛豫频率与（a+κ− 1）-n成正比（α是颗粒半径，κ− 1是双层膜厚度，4.76%和2.38%悬浮液的α弛豫频率分别为0.344和0.308）。指数项n小于稀悬浮液中的指数项（n=2），这可能是由于浓悬浮液中离子在颗粒周围的扩散距离减小所致。颗粒体积分数对电导率增量、Δ K '和α弛豫频率等阻抗参数有影响。由于双电层电荷对电导率增量的正贡献，电导率增量Δ K '随着颗粒体积分数的增加而变得不那么负。α弛豫频率随着颗粒体积分数的增加而增加，并且小颗粒比大颗粒表现出更显着的增加。对二氧化硅悬浮液和水（具有相同电导率值）的微分电阻抗层析图像的实验结果表明，在EIT图像的右上角可以观察到阻抗虚部和相位的值的微小差异，这代表颗粒表面双电层的电极化引起的介电性质的微小差异。
In this paper, the dielectric relaxation of SiO2nano-particle suspensions is studied by electrical impedance spectroscopy method. The case of suspension composed of particles with thick double layer is concerned. The objective of this study is to find out the relationship between particle properties (size and concentration) and electrical impedance spectroscopy for developing a particle characterization method based on electrical impedance spectroscopy/tomography. The influences of particle size on electrical impedance spectroscopy (EIS) and relaxation frequency are investigated and analyzed. The experimental results indicate that impedance phase angle andαrelaxation frequency are functions of particle size.αrelaxation frequency is proportionally changing with (a+κ− 1)-n(ais particle radius,κ− 1is double layer thickness,nequals 0.344 for 4.76% suspension and 0.308 for 2.38% suspension). The exponent term,n, is smaller than the one in dilute suspensions (n=2), which is possibly due to decreasing of diffusion distance of ions around the particles in concentrated suspensions with thick double layer. The impedance parameters, including conductivity increment,ΔK', andαrelaxation frequency are influenced by particle volume fraction. The conductivity increment,ΔK'becomes less negative with increasing particle volume fraction due to the positive contribution of double layer charge on the conductivity increment. Theαrelaxation frequency increases with increasing particle volume fraction and the small particles show a more significant increase than large particles. The experimental result on the differential electrical impedance tomographic images between the silica suspension and water (with same conductivity value) shows that small differences on the values of impedance imaginary part and phase can be observed at the upper right corner in the EIT images, which represent a small differentiation on the dielectric property caused by the electrical polarization of double layer on the particle surface.
登录
查看更多内容
影响因子：
5.2
作者：
M. Thambidurai;N. Muthukumarasamy;D. Velauthapillai;S. Agilan;R. Balasundaraprabhu
通讯作者：
M. Thambidurai;N. Muthukumarasamy;D. Velauthapillai;S. Agilan;R. Balasundaraprabhu
影响因子：
3.9
作者：
J. Kijlstra;H. P. Leeuwen;J. Lyklema
通讯作者：
J. Kijlstra;H. P. Leeuwen;J. Lyklema
影响因子：
15.6
作者：
DUKHIN, SS;SHILOV, VN
通讯作者：
SHILOV, VN
DOI：
10.1016/s0927-7757(97)00272-0
发表时间：
1998-09
期刊：
Colloids and Surfaces A: Physicochemical and Engineering Aspects
影响因子：
--
作者：
Á. Delgado;F. Arroyo;F. González‐Caballero;V. Shilov;Y. Borkovskaya
通讯作者：
Á. Delgado;F. Arroyo;F. González‐Caballero;V. Shilov;Y. Borkovskaya
影响因子：
3.8
作者：
MACDONALD, JR
通讯作者：
MACDONALD, JR