The key difference between positive and negative zeta potential is that the positive zeta potential indicates that the dispersed particles in a suspension are positively charged whereas the negative zeta potential indicates that the dispersed particles in the suspension are negatively charged.
The term zeta potential refers to the electrokinetic potential of colloidal dispersions. Since we use the Greek letter zeta to name this term, we usually call this electrokinetic potential as zeta potential. Moreover, we can simply describe this term as the potential difference between the dispersion medium and the stationary layer of the fluid that attach to the dispersed particle. Therefore, the zeta potential gives an indication of the charge present on the particle surface. It can be either positive or negative. This potential is what we measure as the velocity of the particles in a d.c. electric field.
CONTENTS
1. Overview and Key Difference
2. What is Positive Zeta Potential
3. What is Negative Zeta Potential
4. Side by Side Comparison – Positive vs Negative Zeta Potential in Tabular Form
5. Summary
What is Positive Zeta Potential?
Positive zeta potential indicates that the dispersed particles in the suspension in which we measure the zeta potential have a positive charge. Other than that, considering the values, there is no significant difference between positive and negative zeta potential.
What is Negative Zeta Potential?
Negative zeta potential indicates that the dispersed particles in the suspension that we measure the zeta potential have a negative charge.
Figure 01: The zeta potential in a Colloidal Suspension
Therefore, the charge of the dispersed particles is negative.
What is the Difference Between Positive and Negative Zeta Potential?
Positive zeta potential indicates that the dispersed particles in the suspension in which we measure the zeta potential have a positive charge. On the contrary, negative zeta potential indicates that the dispersed particles in the suspension in which we measure the zeta potential have a negative charge. Therefore, the main difference between positive and negative zeta potential lies upon the electrical charge of the dispersed particles in the suspension that we consider. Other than that, there is no difference between positive and negative zeta potential.
Summary – Positive vs Negative Zeta Potential
The only difference between positive and negative zeta potential is in the electrical charge of the dispersed particles in the suspension of which we measure the zeta potential. Thus, the positive zeta potential indicates that the dispersed particles in a suspension are positively charged. On the other hand, the negative zeta potential indicates that the dispersed particles in the suspension are negatively charged. Therefore, this is the difference between positive and negative zeta potential.
Reference:
1. “Zeta Potential.” Wikipedia, Wikimedia Foundation, 27 Aug. 2018. Available here
Image Courtesy :
1.”Diagram of zeta potential and slipping planeV2″By Larryisgood and Mjones1984 (CC BY-SA 3.0) via Commons Wikimedia