阅读说明：本技术 超薄氮化硅纳米孔膜在反向电渗析发电中的应用及装置 (Application and device of ultrathin silicon nitride nano-pore membrane in reverse electrodialysis power generation ) 是由 马建 曾庆钰 赵佳斌 倪中华 陈云飞 于 2019-09-29 设计创作，主要内容包括：本发明公开了一种超薄氮化硅纳米孔膜在反向电渗析发电中的应用及装置。在反向电渗析发电过程中,采用高浓度盐溶液与低浓度盐溶液形成浓度差,利用氮化硅纳米孔膜阳离子选择性,高浓度盐溶液中的阳离子通过氮化硅纳米孔膜上的纳米孔迁移入低浓度盐溶液,阳离子定向移动形成内电流；高浓度盐溶液中剩余的阴离子在阳极电极表面富集,阳极电极与阴离子发生氧化反应失去电子,电子通过外电路流向低浓度盐溶液侧的阴极电极,阴极电极得到电子发生还原反应,形成回路。本发明从超薄氮化硅纳米孔膜的离子选择性能、机械性能和加工难度这三个方面选择了氮化硅薄膜厚度及孔径,应用在反向电渗析发电中可以获得较高的发电效率。(The invention discloses an application of an ultrathin silicon nitride nano-pore membrane in reverse electrodialysis power generation and a device thereof. In the reverse electrodialysis power generation process, a concentration difference is formed by adopting a high-concentration salt solution and a low-concentration salt solution, cations in the high-concentration salt solution migrate into the low-concentration salt solution through the nano holes in the silicon nitride nano hole film by utilizing the cation selectivity of the silicon nitride nano hole film, and the cations move directionally to form internal current; the residual anions in the high-concentration salt solution are enriched on the surface of the anode electrode, the anode electrode and the anions are subjected to oxidation reaction to lose electrons, the electrons flow to the cathode electrode on the low-concentration salt solution side through an external circuit, and the electrons obtained by the cathode electrode are subjected to reduction reaction to form a loop. The invention selects the thickness and the aperture of the silicon nitride film from the ion selection performance, the mechanical performance and the processing difficulty of the ultrathin silicon nitride nano-pore film, and can obtain higher power generation efficiency when applied to reverse electrodialysis power generation.)

1. An application of an ultrathin silicon nitride nano-pore membrane in reverse electrodialysis power generation.

2. The use of the ultra-thin silicon nitride nanoporous membrane of claim 1 for reverse electrodialysis power generation, wherein: the thickness of the ultrathin silicon nitride nano-pore membrane is 5-20nm, and the pore diameter of the ultrathin silicon nitride nano-pore membrane is 20-100 nm.

3. The use of the ultra-thin silicon nitride nanoporous membrane of claim 1 for reverse electrodialysis power generation, wherein: the preparation method of the ultrathin silicon nitride nano-pore film comprises the following steps: firstly, carrying out double-side polishing on a silicon wafer with the thickness of 300 mu m; depositing a silicon nitride film with the thickness of 100nm on the surface of the silicon wafer by a low-pressure chemical vapor deposition method; then using tetramethyl ammonium hydroxide to etch directionally, etching a 100X 100 μm window on the silicon wafer substrate, thus forming a self-supporting silicon nitride film, then using focused ion beams to thin the self-supporting silicon nitride film, the thinned area is 1-5 μm round, the thickness of the thinned area is controlled at 5-20nm, finally using focused ion beams to sputter a nanopore structure with the aperture of 20-100nm in the thinned area.

4. The use of the ultra-thin silicon nitride nanoporous membrane of claim 1 for reverse electrodialysis power generation, wherein: in the reverse electrodialysis power generation process, a concentration difference is formed by adopting a high-concentration salt solution and a low-concentration salt solution, cations in the high-concentration salt solution migrate into the low-concentration salt solution through the nano holes in the silicon nitride nano hole film by utilizing the cation selectivity of the silicon nitride nano hole film, and the cations move directionally to form internal current; the residual anions in the high-concentration salt solution are enriched on the surface of the anode electrode, the anode electrode and the anions are subjected to oxidation reaction to lose electrons, the electrons flow to the cathode electrode on the low-concentration salt solution side through an external circuit, and the electrons obtained by the cathode electrode are subjected to reduction reaction to form a loop.

5. The use of the ultra-thin silicon nitride nanoporous membrane of claim 4 for reverse electrodialysis power generation, wherein: the high-concentration salt solution and the low-concentration salt solution can adopt the same or different kinds of salt solutions, and the molar concentration ratio of the high-concentration salt solution to the low-concentration salt solution is 10-10000.

6. The use of the ultra-thin silicon nitride nanoporous membrane of claim 4 for reverse electrodialysis power generation, wherein: the high-concentration salt solution adopts 1mol/L potassium chloride solution, and the low-concentration salt solution adopts 0.1mol/L-10^-4A potassium chloride salt solution of mol/L.

7. The use of the ultra-thin silicon nitride nanoporous membrane of claim 4 for reverse electrodialysis power generation, wherein: the electrode in the reverse electrodialysis power generation process adopts a silver/silver chloride electrode.

8. The utility model provides a device that ultra-thin silicon nitride nanopore membrane was used for reverse electrodialysis electricity generation which characterized in that: the device comprises a container for containing a salt solution, wherein the container is divided into two cavities through a silicon nitride nano-pore membrane, a high-concentration salt solution is filled in one cavity, a low-concentration salt solution is filled in the other cavity, an anode electrode is applied to the high-concentration salt solution, a cathode electrode is applied to the low-concentration salt solution, and the anode electrode and the cathode electrode are respectively connected with a load through leads.

9. The device for reverse electrodialysis power generation of the ultra-thin silicon nitride nanoporous membrane of claim 8, wherein: the high-concentration salt solution and the low-concentration salt solution can adopt the same or different kinds of salt solutions, and the molar concentration ratio of the high-concentration salt solution to the low-concentration salt solution is 10-10000.

10. The device for reverse electrodialysis power generation of the ultra-thin silicon nitride nanoporous membrane of claim 8, wherein: the anode electrode and the cathode electrode adopt silver/silver chloride electrodes.

The technical field is as follows:

the invention relates to the technical field of reverse electrodialysis power generation, in particular to application of an ultrathin silicon nitride nano-pore membrane in reverse electrodialysis power generation and a device thereof.

Background art:

with the development of society, the demand of people for energy is increasing day by day. Since the third industrial revolution, electric energy has been widely used in various aspects of human life and production as a practical, economical, clean, and manageable and convertible energy form. The main power generation modes at present are thermal power generation and water conservancy power generation. The former needs to consume non-renewable resources and pollute the environment, and the latter has a large engineering quantity and affects the ecological environment of the local watershed. Therefore, the exploration of an efficient, environment-friendly and easily-controlled power generation mode is in line with the trend of energy development. As a new power generation technique which is being actively studied, the reverse electrodialysis power generation technique utilizes the diffusion effect of ions in a high-concentration salt solution on both sides of an ion permselective membrane to a low-concentration salt solution to generate power. The existing research shows that the development potential of the salt-poor energy is huge, and theoretically, the electric energy of 15102-.

The ion permselective membrane is a core component of the reverse electrodialysis power generation, and the chemical property and the physical property of the ion permselective membrane greatly determine the power and the efficiency of the power generation. There are a large number of commercial membranes available on the market today for reverse electrodialysis power generation, but most membranes are on the micron scale in thickness and pore size, and the power generation efficiency is limited by physical size. With the development of nanotechnology, it is necessary to explore a process for generating electricity by reverse electrodialysis, in which the membrane has a thickness and a pore size in a nanometer scale.

Disclosure of Invention

Aiming at the existing problems, the invention provides the application and the device of the ultrathin silicon nitride nano-porous membrane in reverse electrodialysis power generation, and the invention can improve the acid and alkali resistance of a power generation system and simultaneously improve the power generation power density of a reverse electrodialysis power generation technology.

The above purpose is realized by the following technical scheme:

an application of an ultrathin silicon nitride nano-pore membrane in reverse electrodialysis power generation.

The ultrathin silicon nitride nano-pore membrane is applied to reverse electrodialysis power generation, the thickness of the silicon nitride nano-pore membrane is 5-20nm, and the pore diameter of the ultrathin silicon nitride nano-pore membrane is 20-100 nm.

The application of the ultrathin silicon nitride nano-porous membrane in reverse electrodialysis power generation is characterized in that the manufacturing method of the silicon nitride nano-porous membrane comprises the following steps: firstly, carrying out double-side polishing on a silicon wafer with the thickness of 300 mu m; depositing a silicon nitride film with the thickness of 100nm on the surface of the silicon wafer by a low-pressure chemical vapor deposition method; then, tetramethyl ammonium hydroxide is used for directional etching, and a window of 100 multiplied by 100 mu m is etched on the silicon wafer substrate, thus forming the self-supporting silicon nitride film. And then, utilizing the focused ion beam to thin the self-supporting silicon nitride film, wherein the thinned area is circular with the diameter of 1-5 microns, the thickness of the thinned area can be controlled within 5-20nm, and finally utilizing the focused ion beam to sputter and process a nanopore structure with the pore diameter of 20-100nm in the thinned area, so that compared with the traditional commercial ion exchange film, the thickness of the ion exchange film is greatly reduced, and the reverse electrodialysis power generation power is greatly improved.

In the reverse electrodialysis power generation process, concentration difference is formed by adopting concentration difference between high-concentration salt solution and low-concentration salt solution, cations in the high-concentration salt solution migrate into the low-concentration salt solution through the nano holes in the silicon nitride nano-pore membrane by utilizing cation selectivity of the silicon nitride nano-pore membrane, and the cations move directionally to form internal current; the residual anions in the high-concentration salt solution are enriched on the surface of the anode electrode, the anode electrode and the anions are subjected to oxidation reaction to lose electrons, the electrons flow to the cathode electrode on the low-concentration salt solution side through an external circuit, and the electrons obtained by the cathode electrode are subjected to reduction reaction to form a loop.

The ultrathin silicon nitride nano-porous membrane is applied to reverse electrodialysis power generation, the high-concentration salt solution and the low-concentration salt solution adopt the same type of salt, and the molar concentration ratio of the high-concentration salt solution to the low-concentration salt solution is 10-10000. .

The application of the ultrathin silicon nitride nano-porous membrane in reverse electrodialysis power generation is characterized in that 1mol/L potassium chloride solution is adopted as the high-concentration salt solution, and the low-concentration salt solution is adopted as the low-concentration salt solutionThe salt solution with the concentration of 0.1mol/L-10 is adopted^-4A potassium chloride salt solution of mol/L.

The ultrathin silicon nitride nano-porous membrane is applied to reverse electrodialysis power generation, and a silver/silver chloride electrode is adopted as an electrode in the reverse electrodialysis power generation process.

The utility model provides an ultra-thin silicon nitride nanopore membrane is used for device of reverse electrodialysis electricity generation, the device is including the container that is used for holding the salt solution, divide into two cavitys through silicon nitride nanopore membrane in the container with it, one of them cavity the inside is equipped with high concentration salt solution, and another cavity the inside is equipped with low concentration salt solution, apply the anode electrode in the high concentration salt solution, apply the cathode electrode in the low concentration salt solution, the anode electrode with the cathode electrode is respectively through wire connection load, forms the poor energy power generation system of reverse electrodialysis salt. The silicon nitride nano-porous membrane is used for a device for reverse electrodialysis power generation, the high-concentration salt solution and the low-concentration salt solution adopt the same type of salt, and the molar concentration ratio of the high-concentration salt solution to the low-concentration salt solution is 10-10000. The silicon nitride nano-pore membrane is used for a device for reverse electrodialysis power generation, and the anode electrode and the cathode electrode adopt silver/silver chloride electrodes.

Has the advantages that:

the invention provides application of silicon nitride nanopores in reverse electrodialysis power generation, and the silicon nitride film has good corrosion resistance and can widen the acid-base application range of the silicon nitride film. Meanwhile, the thickness and the aperture of the silicon nitride film are selected from the aspects of cation selectivity, mechanical property and processing difficulty, and the silicon nitride film can obtain higher power generation efficiency when applied to reverse electrodialysis power generation; on the other hand, array nanopores can be processed on the silicon nitride film by utilizing a focused ion beam processing technology, a parallel circuit of reverse electrodialysis nanopore cells can be formed, higher power generation efficiency is obtained, and the method has a good application prospect in the field of reverse electrodialysis power generation.

Drawings

FIG. 1 is a schematic view of the process for forming an ultra-thin silicon nitride film according to the present invention.

Fig. 2 is a schematic view of the device for generating electricity by reverse electrodialysis, which is provided by the invention, of the ultrathin silicon nitride nano-porous membrane.

FIG. 3 is a scanning electron microscope photograph of the silicon nitride nanopores of the present invention.

FIG. 4 is an I-V curve obtained by the power generation method in the example.

FIG. 5 is a graph showing the relationship between the generated power density and the salt concentration difference obtained by the power generation method in the example.

FIG. 6 is a graph of the generated power density and the size of the nanopore aperture obtained by the power generation method in the example.

Detailed Description

In order to more clearly illustrate the present invention, the present invention is further described below with reference to preferred examples and the accompanying drawings.