Zeta potential là gì

Almost all particulate or macroscopic materials in liên hệ with a liquid acquire an electronic charge on their surfaces. Zeta potential is an important và useful indicator of this charge which can be used khổng lồ predict and control the stability of colloidal suspensions or emulsions.

Bạn đang xem: Zeta potential là gì


*
What is Zeta Potential?

Zeta potential is the charge that develops at the interface between a solid surface & its liquid medium. This potential, which is measured in MilliVolts, may arise by any of several mechanisms. Aước ao these are the dissociation of ionogenic groups in the particle surface và the differential adsorption of solution ions into the surface region. The net charge at the particle surface affects the ion distribution in the nearby region, increasing the concentration of counterions cthua trận to the surface. Thus, an electrical double layer is formed in the region of the particle-liquid interface.

This double layer (upper part of figure) consists of two parts: an inner region that includes ions bound relatively tightly khổng lồ the surface, & an outer region where a balance of electrostatic forces & random thermal motion determines the ion distribution. The potential in this region, therefore, decays with increasing distance from the surface until, at sufficient distance, it reaches the bulk solution value, conventionally taken khổng lồ be zero. This decay is shown by the lower part of the figure và the indication is given that the zeta potential is the value at the surface of shear.

Xem thêm: Tại Sao Bị Khóa Facebook Bị Khóa, Cách Khôi Phục Lại Tài Khoản Facebook Bị Khóa

In an electric field, as in microelectrophoresis, each particle & its most closely associated ions move sầu through the solution as a unit, & the potential at the surface of shear between this unit and the surrounding medium is known as the zeta potential. When a layer of macromolecules is adsorbed on the particle’s surface, it shifts the shear plane further from the surface và alters the zeta potential.

Zeta potential is therefore a function of the surface charge of the particle, any adsorbed layer at the interface, và the nature & composition of the surrounding suspension medium. It can be experimentally determined and, because it reflects the effective sầu charge on the particles và is therefore related lớn the electrostatic repulsion between them, the zeta potential has proven khổng lồ be extremely relevant to lớn the practical study and control of colloidal stability & flocculation processes.

Xem thêm: Tính Năng Wifi Hotspot Là Gì ? Cách Sử Dụng Wifi Hotspot Hiệu Quả Nhất ?


Let our friendly và knowledgeable experts help you find the right Zeta Potential instrument for your needs.


Chuyên mục: Hỏi Đáp