An electric double layer of colloidal particles in salt-free concentrated suspensions including non-uniform size effects and orientational ordering of water dipoles

Electrokinetic potential is an important property of colloidal particles and, regarding the fact that it is a well defined and easily measurable property, it is considered to be a permanent characteristic of a particular colloidal system. In fact, it is a measure of electrokinetic charge that surrounds the colloidal particle in a solution and is in direct proportion with the mobility of particles in an electric field. Gouy-Chapman-Stern-Graham's model of electric double layer was adopted and it was proven experimentally that the addition of Cu++ ions to sugar beet pectin caused a reduction in the negative electrokinetic potential proportional to the increase of Cu++ concentration. Higher Cu++ concentrations increased the proportion of cation specific adsorption (Cu++ and H+) with regard to electrostatic Coulombic forces. Consequently, there is a shift in the shear plane between the fixed and diffuse layers directed towards the diffuse layer, i.e. towards its compression and decrease in the electrokinetic potential or even charge inversion of pectin macromolecules.

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Electric Double Layer at the Membrane/Solution Interface: Distribution of Electric Potential and Estimation of the Charge Stored

Berichte der Bunsengesellschaft für physikalische Chemie ◽

10.1002/bbpc.19920960405 ◽

1992 ◽

Vol 96 (4) ◽

pp. 538-544 ◽

Cited By ~ 8

Author(s):

J. A. Manzanares ◽

S. Mafé ◽

J. Bisquert

Keyword(s):

Double Layer ◽

Electric Potential ◽

Electric Double Layer ◽

Solution Interface

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Ion size effects on the electric double layer of a spherical particle in a realistic salt-free concentrated suspension

Physical Chemistry Chemical Physics ◽

10.1039/c1cp20100j ◽

2011 ◽

Vol 13 (20) ◽

pp. 9644 ◽

Cited By ~ 11

Author(s):

Rafael Roa ◽

Félix Carrique ◽

Emilio Ruiz-Reina

Keyword(s):

Spherical Particle ◽

Double Layer ◽

Size Effects ◽

Electric Double Layer ◽

Concentrated Suspension ◽

Ion Size

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Research on the Electrical Model of a Capacitive Soil Moisture Sensor

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.260-261.917 ◽

2012 ◽

Vol 260-261 ◽

pp. 917-925 ◽

Cited By ~ 1

Author(s):

Yan Xu ◽

Wei Dong Yi ◽

Ko Wen Jwo

Keyword(s):

Experimental Data ◽

Soil Moisture ◽

Double Layer ◽

Relative Permittivity ◽

Electric Double Layer ◽

Output Voltage ◽

Sensor Output ◽

Electrical Model ◽

Moisture Sensor ◽

Soil Moisture Sensor

The electrical model of a capacitive soil moisture sensor is considered in this paper. In the new model established, the contact resistor and contact capacitance are taken into account. It is pointed out that the electric double layer causes the formation of the contact resistor and contact capacitance. The electrical properties of the electric double layer are the effect of both physical electricity and electrochemistry, so the relationship between the contact capacitance and the soil relative permittivity does not follow the formula of the parallel plate capacitor. Based upon the diffuse electric double layer model, this paper successfully derives the formula of the contact capacitor , whose coefficients are determined by MATLAB simulation based on experimental data, and the soil relative permittivity. Besides, this paper has established the sensor-output-voltage-Vo -soil-moisture-θ curve and compared it to that derived from the model without considering the electric double layer. It is demonstrated that the correlation coefficient between the curve derived from the model this paper established and the experimental data is 0.9997, more accurately describing the relation between the sensor output voltage Vo and soil moisture θ.

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Visualizing charges accumulated in an electric double layer by three-dimensional open-loop electric potential microscopy

Nanoscale ◽

10.1039/c8nr03600d ◽

2018 ◽

Vol 10 (30) ◽

pp. 14736-14746 ◽

Cited By ~ 2

Author(s):

Kaito Hirata ◽

Takuya Kitagawa ◽

Keisuke Miyazawa ◽

Takahiro Okamoto ◽

Akira Fukunaga ◽

...

Keyword(s):

Double Layer ◽

Electric Potential ◽

Electric Double Layer ◽

Electrode Potential ◽

Three Dimensional ◽

Open Loop ◽

Charge Accumulation ◽

Electrolyte Interface ◽

Accumulation Behavior

Charge accumulation behavior at the Au–electrolyte interface was visualized by three-dimensional open-loop electric potential microscopy with a varying electrode potential.

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Field-induced dipolar attraction between like-charged colloids

Soft Matter ◽

10.1039/c8sm00395e ◽

2018 ◽

Vol 14 (22) ◽

pp. 4520-4529 ◽

Cited By ~ 4

Author(s):

Chunyu Shih ◽

John J. Molina ◽

Ryoichi Yamamoto

Keyword(s):

Numerical Simulations ◽

Electric Fields ◽

Double Layer ◽

Electric Double Layer ◽

Colloidal Particles ◽

Direct Numerical Simulations ◽

Ac Electric Fields ◽

Charged Colloids ◽

Anisotropic Interactions

The field induced anisotropic interactions between like-charged colloidal particles is studied using direct numerical simulations, where the polarization of the electric double layer is explicitly computed under external AC electric fields.

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