Method for reducing stick-slip behaviors of solid and liquid interface under electric field

Abstract

The invention discloses a method for reducing stick-slip behaviors of a solid and liquid interface under an electric field. The method is characterized in that the movement behavior of the micro-liquid droplet on the solid surface can be obviously improved, so that the micro-liquid droplet is more smoothly moved on the solid surface under the electric field; by changing the loading rate of direct-current voltage, the contact line of three phases of the micro-liquid droplet is suddenly changed under the function of high loading rate of direct-current voltage, so that the damping of the solid and liquid interface is overcome, and the stick-slip behaviors of the solid and liquid interface is effectively reduced; by comparing a relationship map of increasing of the length of the contact linesof the three phases of the micro-liquid droplet along with the electric wetting constant at different loading rates of direct-current voltage, the stick-slip behavior of the micro-liquid droplet on the solid and liquid interface at different voltage loading rates can be observed in real time. The method has the advantages that the movement smoothness of the micro-liquid droplet is increased by twotimes or more on the solid surface; the method is mainly based on direct-current programmable power supply, contact angle measurers and image processing software, the experiment method is simple andconvenient, and the result is visual, accurate and reliable.

Description

Technical field [0001] The invention belongs to the technical field of microfluidic control systems, and in particular relates to a method for reducing the stick-slip behavior of a solid-liquid interface under an electric field. Background technique [0002] The microfluidic control system is characterized by a microchannel network and integrates the functions of the entire laboratory on a microchip. It has broad application prospects in biological monitoring, environmental protection, aerospace and other fields. The core technology of the microfluidic control system is the precise driving and control of micro-droplets. Electrowetting on the medium has become one of the most popular micro-droplet driving technologies due to its advantages of low energy consumption, simple preparation and high reliability. Electro-wetting on the medium refers to isolating the conductive surface from the micro-droplets with an insulating layer, and changing the wetting characteristics of the solid...

AI Technical Summary

Problems solved by technology

The stick-slip phenomenon prevents the continuous and smooth movement of micro-droplets on the solid surface, which will have an adverse effect on the precise control of micro-droplets

The stick-slip phenomenon of the three-phase contact line makes it impossible to guarantee the fluency and reliability of products based on electrowetting on the medium, which greatly affects the application and development of electrowetting on the medium technology in products

As far as method 1) is concerned, the surface energy of a solid cannot be reduced endlessly. When the surface energy reaches a certain threshold, the surface energy cannot be further reduced due to the influence of the properties of the material itself; although method 2) can reduce the viscosity of the solid-liquid interface- slipping phenomenon, but this method needs to provide an additional vibration source, the equipment takes up a large space, high energy consumption, and it is difficult to accurately apply tiny vibration energy, so it cannot be applied in actual working conditions; method 3) Although it can Significantly reduce the stick-slip phenomenon of the electrowetting solid-liquid interface on the medium, but requires a dedicated AC power supply

Not only that, as the microfluidic system develops toward miniaturization, miniaturization, and intelligence, its power source is mainly provided by direct current, so the use of alternating current power will make the system more complicated

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