阅读说明：本技术 一种调控液滴带电量和带电性质的方法 (Method for regulating and controlling charge quantity and charge property of liquid drops ) 是由 邓旭 王迎曦 孙强强 于 2020-04-09 设计创作，主要内容包括：本发明公开了一种调控液滴带电量和带电性质的方法。该方法包括以下步骤：(1)在经预处理后的基材表面沉积碳层；(2)继续在碳层上沉积二氧化硅后氟化,得超双疏基材；(3)然后使液滴滴落至超双疏基材表面,即可调整液滴的带电量和带电性质。本发明提供了一种无需外部能量输入、低成本、易操作且能精确调控液滴带电量和带电种类的方法。解决了现有的液滴充电方法中需要使用高压电源充电、操作复杂或难以精确控制液滴带电量和带电种类的问题。(The invention discloses a method for regulating and controlling the charge quantity and charge property of liquid drops. The method comprises the following steps: (1) depositing a carbon layer on the surface of the pretreated base material; (2) continuously depositing silicon dioxide on the carbon layer and then fluorinating to obtain a super-amphiphobic substrate; (3) then the liquid drop is dropped on the surface of the super-amphiphobic base material, and the charge quantity and the charge property of the liquid drop can be adjusted. The invention provides a method which does not need external energy input, has low cost and easy operation and can accurately regulate and control the charged amount and charged species of liquid drops. The problems that a high-voltage power supply is needed to charge, the operation is complex or the charging quantity and the charging type of the liquid drops are difficult to accurately control in the existing liquid drop charging method are solved.)

1. A method for regulating and controlling the charge quantity and the charge property of a liquid drop is characterized by comprising the following steps:

(1) depositing a carbon layer on the surface of the pretreated base material;

(2) continuously depositing silicon dioxide on the carbon layer, sintering for 2-5 h at 500-600 ℃, and then fluorinating for 2-5 h to obtain a super-amphiphobic substrate;

(3) then the liquid drop is dropped on the surface of the super-amphiphobic base material, and the charge quantity and the charge property of the liquid drop can be adjusted.

2. The method of modulating the charge amount and the charge properties of a droplet according to claim 1, wherein the process of positively charging the droplet is:

after the static electricity of the super-amphiphobic base material is eliminated, liquid drops drop at a position 1-10cm above the surface of the base material and impact on the super-amphiphobic base material, and then the positive charge quantity carried by the liquid drops can be adjusted; the higher the drop height of the droplet, the more charged it is.

3. The method of modulating the charge amount and the charge properties of a droplet according to claim 1, wherein the process of positively charging the droplet is: after the static electricity of the super-amphiphobic base material is eliminated, the liquid drop rolls or slides on the super-amphiphobic base material, and the positive charge quantity of the liquid drop can be adjusted; the further the droplet rolls or slides on the super-amphiphobic substrate, the greater the charge.

4. The method of modulating the charge amount and the charge properties of a droplet according to claim 1, wherein the process of positively charging the droplet is:

fluorinating a glass sheet for 2-4H by using 1H,1H,2H, 2H-perfluorooctyl trichlorosilane to obtain a hydrophobic and oleophobic substrate, and then eliminating static electricity of the hydrophobic and oleophobic substrate to ensure that a liquid drop rolls or slides on the hydrophobic and oleophobic substrate, so that the positive charge quantity of the liquid drop can be adjusted; the farther the droplet rolls or slides on the hydrophobic and oleophobic substrate, the more charge it has.

5. The method for regulating the charge amount and the charge property of the liquid drop according to claim 1, wherein the process of making the liquid drop negatively charged is as follows:

the method is characterized in that the method comprises the following steps of eliminating the static electricity of the super-amphiphobic base material, enabling liquid drops to impact the base material from the right top of the surface of the base material for at least 10 times, enabling the base material to be charged negatively, enabling the base material to be close to the upper half part of a container filled with solution, keeping the distance between the base material and the base material constant, enabling the liquid drops in the upper half part of the container to be attracted to be charged positively, enabling the liquid drops extruded out of the lower half part to be charged negatively, and adjusting the charge of the liquid drops dripped out of the lower half part of the container by.

6. The method for modulating the charge amount and the charge property of a liquid droplet according to claim 5, wherein the negative charge of the super-amphiphobic substrate increases with the number of impacts; the negative charge of the droplet increases with increasing negative charge of the super-amphiphobic substrate.

7. The method for regulating the charge amount and the charge property of the liquid drop according to claim 1, wherein the process of making the liquid drop negatively charged is as follows:

eliminate super-amphiphobic substrate static, the liquid drop strikes super-amphiphobic substrate to make super-amphiphobic substrate negatively charged, then through changing the distance between super-amphiphobic substrate and the first half of container, attract the first half in the container to divide the liquid drop positively charged, make the liquid drop that the latter half extrudes negatively charged, thereby can adjust the liquid drop that the latter half of solution dripped and take the negative charge.

8. The method of modulating the charge and charge properties of a droplet of claim 7, wherein the amount of negative charge carried by the droplet decreases with increasing distance between the superamphiphobic substrate and the receptacle.

9. The method for modulating the charge amount and the charge property of a liquid droplet according to claim 5 or 7, wherein the distance between the super-amphiphobic substrate and the container is a transverse pitch or a longitudinal pitch.

10. A method for regulating the charge amount and the charge property of a liquid drop according to any one of claims 2 to 5, wherein the device for measuring the charge amount of the liquid drop is a Faraday cup.

Technical Field

The invention belongs to the technical field of charged liquid regulation, and particularly relates to a method for regulating and controlling the charge quantity and charge property of liquid drops.

Background

Charged droplets are of great interest for their wide application in industry and life, including in the fields of metal ion reduction, electrospray ionization techniques, inkjet printing, material manufacturing (e.g., preparation of nanoparticles, polymer composites), and biomedicine. The micro-nano packaging technology is to generate monodisperse water drops by utilizing electric spraying, and is particularly important in the technical fields of food additive packaging, targeted drug delivery, special material processing and the like.

Currently, the method of charging the liquid droplets by using an external power source includes: charging of the droplets by applying an external electric field; applying pressure to charge the liquid drops flowing through the silica gel channel; applying an overpressure (-100 KPa) drives the droplets through the pore charging, etc. Other methods have been developed that do not require additional power and equipment, such as dropping droplets from microtubes, causing the droplets to rub against the walls of the tube for charging; the droplets are triboelectrically charged through the cylindrical tube by flowing the droplets through an L-shaped channel or by using the gravitational energy of water.

Therefore, the existing technology for charging the liquid drops either needs an external high-voltage power supply and is high in cost, or cannot accurately control the liquid drop charging amount and the charging type.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a method for regulating and controlling the charge quantity and the charge property of liquid drops, and provides a method which does not need external energy input, has low cost and easy operation and can accurately regulate and control the charge quantity and the charge type of the liquid drops. The problems that a high-voltage power supply is needed to charge, the operation is complex or the charging quantity and the charging type of the liquid drops are difficult to accurately control in the existing liquid drop charging method are solved.

In order to achieve the purpose, the technical scheme adopted by the invention for solving the technical problems is as follows:

a method for regulating and controlling the charge quantity and the charge property of a liquid drop comprises the following steps:

(1) depositing a carbon layer on the surface of the pretreated base material;

(2) continuously depositing silicon dioxide on the carbon layer, sintering for 2-5 h at 500-600 ℃, and then fluorinating for 2-5 h to obtain a super-amphiphobic substrate;

(3) then the liquid drop is dropped on the surface of the super-amphiphobic base material, and the charge quantity and the charge property of the liquid drop can be adjusted.

Further, the process of positively charging the droplets is:

after the static electricity of the super-amphiphobic base material is eliminated, liquid drops drop at a position 1-10cm above the surface of the base material and impact on the super-amphiphobic base material, and then the positive charge quantity carried by the liquid drops can be adjusted; the higher the drop height of the droplet, the more charged it is.

Further, the process of positively charging the droplets is: after the static electricity of the super-amphiphobic base material is eliminated, the liquid drop rolls or slides on the super-amphiphobic base material, and the positive charge quantity of the liquid drop can be adjusted; the further the droplet rolls or slides on the super-amphiphobic substrate, the more charged it becomes.

Further, the process of positively charging the droplets is:

fluorinating a glass sheet for 2-4H by using 1H,1H,2H, 2H-perfluorooctyl trichlorosilane to obtain a hydrophobic and oleophobic substrate, and then eliminating static electricity of the hydrophobic and oleophobic substrate to ensure that a liquid drop rolls or slides on the hydrophobic and oleophobic substrate, so that the positive charge quantity of the liquid drop can be adjusted; the farther a droplet rolls or slides on the hydrophobic and oleophobic substrate, the more charge it has.

Further, the process of negatively charging the droplets is:

the method is characterized in that the method comprises the following steps of eliminating the static electricity of the super-amphiphobic base material, enabling liquid drops to impact the base material from the right top of the surface of the base material for at least 10 times, enabling the base material to be charged negatively, enabling the base material to be close to the upper half part of a container filled with solution, keeping the distance between the base material and the base material constant, enabling the liquid drops in the upper half part of the container to be attracted to be charged positively, enabling the liquid drops extruded out of the lower half part to be charged negatively, and adjusting the charge of the liquid drops dripped out of the lower half part of the container by.

Further, the negative charge of the super-amphiphobic substrate increases with the number of impacts; the negative charge of the droplet increases with increasing negative charge of the super-amphiphobic substrate.

Further, the process of negatively charging the droplets is:

eliminate super-amphiphobic substrate static, the liquid drop strikes super-amphiphobic substrate to make super-amphiphobic substrate negative electricity, then through adjusting the distance between super-amphiphobic substrate and the first half of container, the first half divides the liquid drop positive electricity in the attraction container, makes the liquid drop that the latter half was extruded negative electricity, thereby can adjust the liquid drop that the latter half of solution dripped negative electricity.

Further, the amount of negative charge carried by the droplet decreases with increasing distance between the superamphiphobic substrate and the container.

Further, the distance between the super-amphiphobic substrate and the container is a transverse spacing or a longitudinal spacing.

Further, the device for measuring the electric quantity of the liquid drop is a Faraday cup.

The invention has the beneficial effects that:

the invention can effectively control the charged quantity of the liquid drop according to the dropping height, the dropping frequency, the sliding distance and the like of the liquid drop and can control the charged property of the liquid drop. The method has the advantages of no need of external energy input, low cost, easy operation and capability of accurately regulating and controlling the charge amount and the charge type of the liquid drops.

Drawings

FIG. 1 is a process of generating positive charges in a droplet;

FIG. 2 is a process of generating negative charges in a droplet;

FIG. 3 is a graph of surface potential of a superamphiphobic substrate as a function of the number of droplet strikes.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.