阅读说明：本技术 一种基于纳流体二极管的水伏器件及其制备方法 (Nano-fluid diode-based photovoltaic device and preparation method thereof ) 是由 杨婷婷 张勇 卢旭磊 何其昌 于 2021-09-09 设计创作，主要内容包括：本发明公开了一种基于纳流体二极管的水伏器件,从下到上依次包括基底层、下电极和上电极,上电极与下电极之间设有敏感层；敏感层为两层具有相反ZETA电位的薄膜构成的PN结,或者为两层相反ZETA电位的薄膜中间再加一层ZETA电位近似为0的薄膜构成PIN结；敏感层各层均是连通的孔结构,其中至少有一层含有0.1-100nm尺寸的纳米级连通孔。本发明通过将纳流体二极管引入水伏器件,使水伏器件的性能有很大提升,该器件无需额外能耗,绿色环保,且器件结构简单,制备方法中的制备工艺容易操作,所需材料容易获取并且价格低廉,适合大规模生产。(The invention discloses a nanofluid diode-based photovoltaic device which sequentially comprises a substrate layer, a lower electrode and an upper electrode from bottom to top, wherein a sensitive layer is arranged between the upper electrode and the lower electrode; the sensitive layer is a PN junction formed by two films with opposite ZETA potentials, or a PIN junction formed by adding a film with a ZETA potential approximate to 0 between the two films with opposite ZETA potentials; all the sensitive layers are communicated pore structures, wherein at least one layer contains nano-scale communicating pores with the size of 0.1-100 nm. According to the invention, the nano-fluid diode is introduced into the photovoltaic device, so that the performance of the photovoltaic device is greatly improved, the device does not need extra energy consumption, is green and environment-friendly, and has a simple structure, the preparation process in the preparation method is easy to operate, the required materials are easy to obtain and low in price, and the nano-fluid diode is suitable for large-scale production.)

1. A photovoltaic device based on a nano-fluid diode is characterized by sequentially comprising a substrate layer, a lower electrode and an upper electrode from bottom to top, wherein a sensitive layer is arranged between the upper electrode and the lower electrode;

the sensitive layer is a PN junction formed by two films with opposite ZETA potentials, or a PIN junction formed by adding a film with a ZETA potential approximate to 0 between the two films with opposite ZETA potentials;

all the sensitive layers are communicated pore structures, wherein at least one layer contains nano-scale communicating pores with the size of 0.1-100 nm.

2. The nanofluid diode-based photovoltaic device according to claim 1, wherein the upper electrode is directly used as a P layer or an N layer in the sensitive layer if the upper electrode itself has a surface charge or is chemically modified, that is, the ZETA potential is not zero; if the lower electrode has surface charges or has surface charges after chemical modification, namely the ZETA potential is not zero, the lower electrode is directly used as an N layer or a P layer in the sensitive layer;

the sensitive layer comprises: the upper electrode and another film with opposite ZETA potential form a PN junction, or the lower electrode and another film with opposite ZETA potential form a PN junction, or the upper electrode and the lower electrode with opposite ZETA potential directly form a PN junction.

3. The nanofluidic diode-based photovoltaic device of claim 1, wherein the upper electrode is made of a material with gas permeability and electrical conductivity, and the lower electrode is made of a material with electrical conductivity.

4. The nanofluidic diode-based photovoltaic device of claim 1, wherein the base layer is configured to form wetting gradient differences and provide mechanical support to the photovoltaic device.

5. The method for preparing a nano-fluid diode-based photovoltaic device as claimed in any one of claims 1 to 4, comprising the following steps:

s1, fixing the lower electrode on the substrate layer, and connecting a lead on the lower electrode;

s2, tightly connecting the layers of the sensitive layer in sequence;

s3, fixing the sensitive layer on the lower electrode;

and S4, tightly connecting the upper electrode with the sensitive layer, wherein the upper electrode is not communicated with the lower electrode, and a lead is connected to the upper electrode.

Technical Field

The invention belongs to the technical field of novel energy collection, and particularly relates to a nano-fluid diode-based photovoltaic device and a preparation method thereof.

Background

Conventional energy harvestingThe technology is mainly focused on specific facilities that convert energy into electrical energy using fossil fuels, wind currents and water currents. However, its deployment worldwide is severely hampered by extremely high cost, complex engineering facilities and limited geographical requirements, particularly in underdeveloped or remote countries that often suffer from capital shortages and infrastructure lags. In this regard, some off-grid, decentralized technologies have been developed as a supplement to centralized power grids. Such as solar cells, piezoelectric nanogenerators, triboelectric nanogenerators, and thermoelectric nanogenerators, convert solar energy, mechanical energy, and thermal energy into electrical energy. However, the above power generation is limited by specific climatic conditions, which limits its further applications. The water covers 71% of the earth's surface, including oceans, rivers, glaciers, etc., and the atmosphere is also filled with invisible water vapor or water mass. The conversion between different forms of water, such as ice, reversible transitions between liquids and vapors, constitutes the global water cycle and provides a tremendous exchange of energy. The basic energy in the dynamic water circulation is about 6 x 10 per year¹⁶Watts, orders of magnitude higher than the average consumption of electrical energy by human activity. In addition, water is ubiquitous in animals, plants and their common activities. However, it is not uncommon to use the moisture diffusion process in nature directly for the generation of electrical energy. The nano material has obvious quantum effect and surface effect, can be coupled with water in various forms to output obvious electric signals, for example, graphene can directly convert the energy of dragging and falling water drops into electric energy through the boundary motion of an electric double layer, and can also convert the wave energy of seawater into electric energy. Nano-structured materials such as carbon black can continuously generate electric energy in volt level through natural evaporation of ubiquitous water in atmospheric environment. This phenomenon of direct generation of electricity by the interaction of water with functional materials is called the "hydrophytic effect". The hydroelectric effect opens up a brand new direction for capturing the water energy of the earth water circulation in a full-chain manner, and the water energy utilization capacity is improved.

The existing photovoltaic device mainly depends on self materials or structures for generating electricity, and generates ion concentration gradient after the action of water molecules, so that the ions are promoted to move directionally to generate electric energy. The water molecules are provided in the form of air humidity, water droplets, or water-coated water. However, the existing device design still has the problems of low output power density, poor long-term stability, single working mode and the like. There is an urgent need to explore film materials and device designs with new sustained energy conversion mechanisms to achieve high output power density and improve long-term stability of output and extend the operating modes for the devices. In addition, the research time of the hydro-voltaic effect is short, the significance is great, and further deep research is urgently needed.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, provides the photovoltaic device based on the nano-fluid diode with simple structure and low cost, and introduces the nano-fluid diode into the photovoltaic device, so that the performance of the photovoltaic device is greatly improved; the preparation method of the photovoltaic device is simple to operate, the required materials are easy to obtain, the cost is low, and the preparation method is suitable for large-scale production.

The purpose of the invention is realized by the following technical scheme: a photovoltaic device based on a nano-fluid diode sequentially comprises a basal layer, a lower electrode and an upper electrode from bottom to top, wherein a sensitive layer is arranged between the upper electrode and the lower electrode;

the sensitive layer is a PN junction formed by two films with opposite ZETA potentials, or a PIN junction formed by adding a film with a ZETA potential approximate to 0 between the two films with opposite ZETA potentials;

all the sensitive layers are communicated pore structures, wherein at least one layer contains nano-scale communicating pores with the size of 0.1-100 nm.

Further, if the upper electrode has surface charges or has surface charges after chemical modification, namely the ZETA potential is not zero, the upper electrode is directly used as a P layer or an N layer in the sensitive layer; if the lower electrode has surface charges or has surface charges after chemical modification, namely the ZETA potential is not zero, the lower electrode is directly used as an N layer or a P layer in the sensitive layer;

the sensitive layer comprises: the upper electrode and another film with opposite ZETA potential form a PN junction, or the lower electrode and another film with opposite ZETA potential form a PN junction, or the upper electrode and the lower electrode with opposite ZETA potential directly form a PN junction.

Furthermore, the upper electrode is made of a material with air permeability and conductivity, and the lower electrode is made of a material with conductivity.

Further, the base layer is used to form a wetting gradient difference and provide mechanical support to the photovoltaic device.

Another object of the present invention is to provide a method for preparing a nanofluid diode-based photovoltaic device, comprising the following steps:

s1, fixing the lower electrode on the substrate layer, and connecting a lead on the lower electrode;

s2, tightly connecting the layers of the sensitive layer in sequence;

s3, fixing the sensitive layer on the lower electrode;

and S4, tightly connecting the upper electrode with the sensitive layer, wherein the upper electrode is not communicated with the lower electrode, and a lead is connected to the upper electrode.

The invention has the beneficial effects that:

(1) by introducing the nano-fluid diode into the photovoltaic device, the performance of the photovoltaic device is greatly improved, such as higher output voltage, higher power density, and multiple operation modes of water drop operation, air humidity operation and water covered operation.

(2) The power generation principle of the device is as follows: water molecules are transported to the sensitive layer through the upper electrode, ionized into anions and cations on one side of the sensitive layer close to the air, and then selective ion directional transportation is realized through an internal electric field generated by a PN junction and a Debye shielding effect of the nano flow channel, so that the anions and the cations are spatially separated in the sensitive layer. The sensitive layer, the upper electrode, the lower electrode and an external load form an electric loop, so that voltage and current are continuously generated. The power generation principle is novel, no extra energy consumption is needed, and the power generation device is green and environment-friendly.

(3) The device designed by the invention has a simple structure, the preparation process in the preparation method is easy to operate, the required materials are easy to obtain, the price is low, and the device is suitable for large-scale production.

Drawings

FIG. 1 is a block diagram of a nanofluid diode-based photovoltaic device according to the present invention;

FIG. 2 is a schematic diagram of the power generation concept of the present invention;

fig. 3 is a schematic diagram of a device of example 1 of the present invention.

Detailed Description

The fluid moves in a nano-sized confined space where the ionized ions have similarities in many respects to the carriers in the semiconductor. In the nanopore, a material with a negatively charged surface can be regarded as a P-type semiconductor, and a material with a positively charged surface can be regarded as an N-type semiconductor. The nano-fluid diode has a rectifying effect similar to a semiconductor PN junction. The structural design of the device is mainly to form a nano-fluid diode with PN junction rectification effect by constructing a nano-pore heterojunction with different charges on the surface, so as to realize the adsorption and ionization of water molecules and the selective and directional transportation of ions, thereby achieving the power generation effect. The device comprises a sensitive layer, an electrode layer and a substrate layer. Wherein, the sensitive layer and the electrode layer with good hydrophilicity are selected, so that the water molecules in the air can be captured conveniently to form continuous motion in the nano-channel.

The technical scheme of the invention is further explained by combining the attached drawings.

As shown in fig. 1, the photovoltaic device based on the nano-fluid diode of the present invention sequentially includes, from bottom to top, a substrate layer, a lower electrode and an upper electrode, wherein a sensitive layer is disposed between the upper electrode and the lower electrode;

the sensitive layer is a PN junction formed by two films with opposite ZETA potentials, or a PIN junction formed by adding a film with a ZETA potential approximate to 0 between the two films with opposite ZETA potentials;

each layer of the sensitive layer is of a communicated pore structure, so that water molecules and ions can be conveniently transmitted; at least one layer of the nano-scale communicating holes with the size of 0.1-100nm is contained, and the selective and directional transport of ions inside the nano-scale communicating holes is realized due to the Debye effect and the discharge and enrichment effect of the charged nano-scale holes.

The power generation principle of the invention is as follows: water molecules are transported to the sensitive layer through the upper electrode, ionized into anions and cations on one side of the sensitive layer close to the air, and then selective ion directional transportation is realized through an internal electric field generated by a PN junction and a Debye shielding effect of the nano flow channel, so that the anions and the cations are spatially separated in the sensitive layer. The sensitive layer, the upper electrode, the lower electrode and the external load form an electrical loop, so that voltage and current are continuously generated, as shown in fig. 2 and 3. In the figure, the size of the N layer pore channel is 0.1-100nm, the P layer is a communicated pore structure, so that water molecules and ions are conveniently transported, fixed charges are provided for each channel of the N layer in the figure, and the surface of the whole P layer is provided with the fixed charges.

If the upper electrode has surface charges or has surface charges after chemical modification, namely the ZETA potential is not zero, the upper electrode is directly used as a P layer or an N layer in the sensitive layer; if the lower electrode has surface charges or has surface charges after chemical modification, namely the ZETA potential is not zero, the lower electrode is directly used as an N layer or a P layer in the sensitive layer;

the sensitive layer comprises: the upper electrode and another film with opposite ZETA potential form a PN junction, or the lower electrode and another film with opposite ZETA potential form a PN junction, or the upper electrode and the lower electrode with opposite ZETA potential directly form a PN junction. Based on the above requirements, AAO (anodic aluminum oxide) with positive potential and modified CNT (carbon nano tube) with negative potential can be selected.

The upper electrode is made of a material with air permeability and conductivity, and the lower electrode is made of a material with conductivity. The upper electrode is preferably made of hydrophilic materials except for air permeability and conductivity, if the upper electrode is good in hydrophilicity, the water collecting capacity is better, sufficient water can be provided, the output of the device can be improved, and modified carbon nanotubes, bionic nanocone carbon nanofibers and the like can be adopted; the lower electrode is preferably made of a material having hydrophilicity, such as gallium-indium alloy, in addition to being required to have conductivity.

The base layer is used for forming a wetting gradient difference, namely the base layer is closely contacted with the lower electrode, so that the moisture exchange between the lower electrode and air can be prevented, the upper electrode is directly contacted with the air, the moisture exchange is faster than that of the lower electrode, and the wetting gradient difference is formed between the upper electrode and the lower electrode; and providing mechanical support to the photovoltaic device. If the sensitive layer is made of rigid materials, the substrate layer is a glass slide or other rigid substrates; if the sensitive layer is made of flexible materials, the substrate layer is made of flexible materials such as polyester, polyimide and the like.

Example 1

The N layer is made of Anodic Aluminum Oxide (AAO), the P layer is made of a modified carbon nanotube film (the modification is to change the carbon nanotube film into hydrophilic and increase more surface charges), the modification method is to use an oxygen plasma cleaner to clean the carbon nanotube film for 9 minutes under the power of 29.6W, and the P layer and the upper electrode layer are made of the same material; the lower electrode is made of hydrophilic gallium-indium alloy, and the upper electrode is a modified carbon nanotube (the upper electrode is simultaneously used as a P layer of the sensitive layer); the substrate is selected from a glass slide. The preparation method of the nano-fluid diode-based photovoltaic device comprises the following steps:

s1, cleaning the glass slide, placing a proper amount of gallium-indium alloy (about 100 microliter) in the center of the glass slide, spreading the gallium-indium alloy by a blade, and making the area of the gallium-indium alloy be about 1.5 x 3cm²As a lower electrode, and then a lead is connected to the lower electrode;

s2, washing the AAO (diameter 13mm, thickness 50 μm) with oxygen plasma for 9 minutes, then sealing the periphery of the treated AAO with a transparent adhesive tape, and leaving the central part as a sensitive area;

s3, fixing the AAO with the outer side sealed on the gallium-indium alloy of the lower electrode by using a transparent adhesive tape, and completely coating the periphery of the gallium-indium alloy along the tape to prevent diffusion;

s4, transferring a carbon nanotube film with the thickness of 150nm to AAO, dripping alcohol on the carbon nanotube on a PTFE substrate to completely wet the carbon nanotube and then attach the carbon nanotube to the AAO, covering the reserved AAO completely, and slowly drawing out the PTFE substrate to finish the transfer; after the alcohol is completely volatilized, avoiding AAO (anodic aluminum oxide) on one side of the carbon nano tube, tightly connecting the conducting wire and the carbon nano tube by using conductive silver adhesive, then putting the conducting wire and the carbon nano tube on a hot plate at 60 ℃ to accelerate the solidification of the silver adhesive, after the silver adhesive is solidified, sealing the silver adhesive by using the AB adhesive, then waiting for the solidification of the AB adhesive, after the solidification, putting the device into a plasma cleaner to be treated by using oxygen plasma, and after the treatment, completing the manufacturing of the photovoltaic device. In the device use state, as shown in fig. 3, the leads passing through the upper and lower electrodes are connected to an external load.

Example 2

The N layer is AAO; the P layer is a carbon nanofiber film with a bionic nanocone structure, and the P layer and the upper electrode are made of the same material; the lower electrode is made of hydrophilic gallium-indium alloy; selecting a glass slide as a substrate; the preparation method of the nano-fluid diode-based photovoltaic device comprises the following steps:

s1, cleaning the glass slide, placing a proper amount of gallium-indium alloy (about 100 microliter) in the center of the glass slide, spreading the gallium-indium alloy by a blade, and making the area of the gallium-indium alloy be about 1.5 x 3cm²Then, a lead is connected to one side of the lead;

s2, washing the AAO (diameter 13mm, thickness 50 μm) with oxygen plasma for 9 minutes, then sealing the periphery of the treated AAO with a transparent adhesive tape, and leaving the central part as a sensitive area;

s3, fixing the AAO obtained by sealing the outer side of the lower electrode to the gallium-indium alloy by using a transparent adhesive tape, and completely coating the gallium-indium alloy along the tape to prevent the gallium-indium alloy from diffusing to other positions;

s4, transferring the carbon nanofiber film with the bionic nanocone structure to AAO for tight connection, tightly connecting a lead and an upper electrode on one side of the carbon nanofiber with the bionic nanocone by conductive silver adhesive, then placing the carbon nanofiber film on a hot plate at 60 ℃ to accelerate silver adhesive curing, sealing the silver adhesive by AB adhesive after the silver adhesive is cured, waiting for the AB adhesive to be cured, and finishing the manufacturing of the photovoltaic device after the curing.

Example 3

The N layer is made of porous nanofiber (self-made porous structure with nanometer level and positive ZETA potential), and the P layer is made of the modified carbon nanotube film in the embodiment 1; the lower electrode is made of hydrophilic gallium-indium alloy, and the upper electrode is a modified carbon nanotube; the substrate was Polyester (PET) and was of the same specification as the glass slide. The preparation method of the nano-fluid diode-based photovoltaic device comprises the following steps:

s1, cleaning the substrate, placing a proper amount of gallium-indium alloy (about 100 microliter) in the center of the substrate, spreading the gallium-indium alloy by a blade, and making the gallium-indium alloy have an area of about 1.5 x 3cm²Then, a lead is connected to one side of the lead;

s2, cleaning porous nanofibers (with the diameter of 13mm and the thickness of 50 microns) for 9 minutes by using oxygen plasma, then tightly attaching the modified carbon nanotube film and the porous nanofibers to form a sensitive layer, sealing the periphery of the sensitive layer by using a transparent adhesive tape, and reserving the central part as a sensitive area;

s3, fixing the sensitive layer with sealed outside on the lower electrode gallium indium alloy by a transparent adhesive tape, and completely coating the gallium indium alloy in the same direction to prevent the gallium indium alloy from diffusing to other positions;

s4, transferring a 150 nm-thick carbon nanotube film onto a sensitive layer, wherein the carbon nanotube is placed on a PTFE substrate, alcohol is dripped on the carbon nanotube to completely wet the carbon nanotube film and then the carbon nanotube film is attached onto the sensitive layer, the reserved sensitive layer is completely covered, and then the PTFE substrate is slowly drawn out to finish the transfer; after the alcohol is completely volatilized, the sensitive layer is kept away from one side of the carbon nano tube, the conducting silver adhesive is used for tightly connecting the conducting wire and the carbon nano tube, then the conducting silver adhesive is placed on a hot plate at 60 ℃ for accelerating the solidification of the silver adhesive, after the silver adhesive is solidified, the AB adhesive is used for sealing the silver adhesive, then the AB adhesive is used for solidifying, after solidification, the device is placed into a plasma cleaning machine for treating by oxygen plasma, and after treatment, the manufacturing of the photovoltaic device is completed.

It will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.