1. A red phosphorus photoelectrode characterized in that: comprises a substrate, wherein the surface of the substrate is loaded with crystal phase red phosphorus.

2. According toThe red phosphorus photoelectrode of claim 1, wherein: the loading amount of the crystal phase red phosphorus is 0.01mg/cm²～10mg/cm²。

3. The red phosphorus photoelectrode of claim 1, wherein: the length of the substrate is 1.0 cm-20.0 cm, and the width of the substrate is 0.1 cm-2.0 cm.

4. The red phosphorus photoelectrode of claim 1, wherein: the substrate is selected from any one of a carbon sheet, a carbon cloth, a tungsten sheet, a molybdenum sheet and a tungsten mesh.

5. A method for producing a red phosphorus photoelectrode according to any one of claims 1 to 4, characterized in that: the method comprises the following steps: a substrate is obtained, and red phosphorus is grown on the surface of the substrate.

6. The method for producing a red phosphorus photoelectrode according to claim 5, characterized in that: the red phosphorus grows on the substrate by adopting a thermal chemical vapor deposition method; the thermal chemical vapor deposition method comprises the following steps: and (3) heating the substrate under vacuum to grow red phosphorus, and cooling to room temperature after the growth is finished.

7. The method for producing a red phosphorus photoelectrode according to claim 5, characterized in that: in the process of the thermal chemical vapor deposition method, the temperature of the substrate is raised to 500-600 ℃ under vacuum.

8. The method for producing a red phosphorus photoelectrode according to claim 5, characterized in that: the temperature rise rate is (1-20) DEG C/min.

9. The method for producing a red phosphorus photoelectrode according to claim 5, characterized in that: the cooling rate is (0.1-1.0) DEG C/min.

10. The application of the red phosphorus photoelectrode as claimed in any one of claims 1 to 4 or the red phosphorus photoelectrode prepared by the method as claimed in any one of claims 5 to 9 in a photoelectrocatalysis anode material.

Background

Energy problems are a major challenge facing today. Solar energy is a renewable, sustainable energy source. How to develop and utilize solar energy is an important research topic today. The photoelectrocatalysis technology is a technology which combines photocatalysis and electrocatalysis technology and efficiently utilizes solar energy. Photovoltaic cells consist of an anode and a cathode. Under the drive of light and electricity, a photoanode which is generally composed of a semiconductor generates a photogenerated positive electrode (holes) and a photogenerated negative electrode (electrons) under illumination, the electrons migrate to a cathode, and the process generates current and electric energy. And the surface of the photo-anode is subjected to oxidation reaction, and generally, water is oxidized into oxygen. The electrons on the photocathode can reduce water to generate clean energy hydrogen.

At present, the research is focused on finding and preparing efficient photo-anode materials, and the traditional metal oxide or sulfide photo-anode materials have narrow light absorption range and absorb ultraviolet light or a part of visible surfaces. In addition, the recombination of electrons and holes is serious, and the generated current is often relatively small (less than 2 mA/cm)²)。

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art described above. To this end, the present invention proposes, in a first aspect, a red phosphorus photoelectrode capable of generating electric energy and/or hydrogen energy.

The second aspect of the invention provides a preparation method of the red phosphorus photoelectrode.

The third aspect of the invention proposes an application of the red phosphorus photoelectrode.

According to a first aspect of the present invention, there is provided a red phosphorus photoelectrode comprising a substrate having a surface supporting crystalline phase red phosphorus.

In some embodiments of the invention, the red phosphorus is a nanorod.

In some preferred embodiments of the present invention, the nanorods have a diameter of 100nm to 1.0. mu.m.

In some preferred embodiments of the present invention, the loading amount of the red phosphorus is 10mg to 1000 mg; further preferably 0.01mg/cm²～10mg/cm²。

In some preferred embodiments of the present invention, the substrate has a length of 1.0cm to 20.0cm and a width of 0.1cm to 2.0 cm.

In some more preferred embodiments of the present invention, the substrate is selected from any one of a carbon sheet, a carbon cloth, a tungsten sheet, a molybdenum sheet, and a tungsten mesh.

According to a second aspect of the present invention, there is provided a method for manufacturing a red phosphorus photoelectrode, comprising the steps of: a substrate is obtained, and red phosphorus is grown on the surface of the substrate.

In some embodiments of the invention, the red phosphorus is grown on the substrate using thermal chemical vapor deposition; the thermal chemical vapor deposition method comprises the following steps: and (3) heating the substrate under vacuum to grow red phosphorus, and cooling to room temperature after the growth is finished.

In the invention, the thermal chemical vapor deposition method is adopted to sublimate and desublimate the red phosphorus, so that the crystalline phase red phosphorus nanorod grows on the substrate.

In some preferred embodiments of the present invention, the thermal chemical vapor deposition process is carried out in a quartz tube.

In some preferred embodiments of the present invention, the quartz tube has a thickness of 0.1mm to 0.3mm and a length of 10cm to 30 cm.

In some more preferred embodiments of the present invention, during the thermal chemical vapor deposition process, the substrate is warmed to 500 ℃ to 600 ℃ under vacuum.

In some more preferred embodiments of the present invention, the rate of temperature rise is (1-20) ° c/min.

In some more preferred embodiments of the present invention, the rate of cooling is (0.1-1.0) deg.C/min.

According to a third aspect of the present invention, there is provided a use of a red phosphorus photoelectrode as a photocatalytic anode material.

When the red phosphorus photoelectrode is used as an anode material in photoelectrocatalysis, the red phosphorus photoelectrode can generate photocurrent and/or hydrogen energy, and particularly can generate the maximum of 8mA/cm²And hydrogen production of 1.89mL per hour was achieved.

The invention has the beneficial effects that:

1. the red phosphorus photoelectrode has simple composition, the raw material red phosphorus is cheap, and the red phosphorus photoelectrode is beneficial to wide popularization.

2. The red phosphorus photoelectrode of the invention has simple preparation method and low cost.

3. When the red phosphorus photoelectrode is applied to an anode material in photoelectrocatalysis, the red phosphorus photoelectrode can simultaneously generate electric energy and hydrogen energy, and the maximum generated energy is 8.0mA/cm²And hydrogen production of 1.89mL per hour was achieved.

Drawings

The invention is further described with reference to the following figures and examples, in which:

FIG. 1 is a photograph and a photoelectrode electron microscopic scan of a quartz tube before and after heat treatment in example 1 of the present invention.

FIG. 2 is an electron microscope scanning image of a tungsten mesh substrate of the present invention prepared in example 1.

FIG. 3 is a current-voltage relationship diagram of the photo-catalysis generated current of the crystal phase red phosphorus photoelectrode of the tungsten mesh substrate prepared in example 1 of the present invention.

FIG. 4 is a graph showing the current of the crystal phase red phosphorus photoelectrode of the tungsten mesh substrate obtained in example 1 of the present invention in the presence and absence of light at a voltage of 0.9V.

FIG. 5 is an electron micrograph (b) of a red phosphorescent electrode as a crystal phase on the tungsten plate substrate obtained in example 3, and a current-voltage relationship (a) of current generation by photocatalysis.

FIG. 6 is an electron microscope scan (b) of the crystal phase red phosphor electrode of the molybdenum plate substrate obtained in example 4 and a current-voltage relationship (a) of current generation under photocatalysis.

FIG. 7 is an electron micrograph (a) of a red phosphor photoelectrode of a crystal phase of the titanium plate substrate obtained in example 5 and a current-voltage relationship (a) of a current generated by photocatalysis.

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.

Example 1

In this embodiment, a crystalline phase red phosphorus photoelectrode (CP/W) of a tungsten mesh substrate is prepared, and the specific process is as follows:

200mg of red phosphorus and a 1.0cm wide by 20.0cm long tungsten mesh substrate were weighed, sealed in a quartz capsule, and evacuated. Then the quartz tube is put into a furnace, the temperature is raised to about 550 ℃ at the heating rate of 1.0 ℃/min, and the quartz tube is cooled to the normal temperature at the speed of 0.1 ℃/min after being protected for 15 hours. Then breaking the quartz tube, taking out the substrate, and then washing the substrate with water and ethanol to prepare the red phosphorus photoelectrode.

FIG. 1 is a photograph and an electron microscope scan of a quartz tube before and after heat treatment. As can be seen from fig. 1, red phosphorus is deposited on the tungsten mesh after heat treatment.

The red phosphorus photoelectrode after heat treatment was subjected to electron microscope scanning, and the result is shown in fig. 2. As can be seen from FIG. 2, the red phosphorus grown on the tungsten mesh is of a nanorod structure, with a diameter of 0.1 μm to 0.5 μm and a length of 1.0 μm to 10.0. mu.m.

Example 2

In this embodiment, a crystalline phase red phosphorus photoelectrode (CP/W plate) of a tungsten plate substrate is prepared, and the specific process is as follows:

200mg of red phosphorus and a 1.0cm wide, 3.0cm long, 0.2cm thick tungsten metal substrate were weighed, sealed in a quartz capsule, and evacuated. Then the quartz tube is put into a furnace, the temperature is raised to about 550 ℃ at the heating rate of 1.0 ℃/min, and the quartz tube is cooled to the normal temperature at the speed of 0.1 ℃/min after being protected for 15 hours. Then breaking the quartz tube, taking out the substrate, and then washing the substrate with water and ethanol to prepare the red phosphorus photoelectrode.

Example 3

In this embodiment, a crystalline phase red phosphorus photoelectrode (CP/Mo plate) of a molybdenum sheet substrate is prepared, and the specific process is as follows:

200mg of red phosphorus and a 1.0cm wide, 3.0cm long, 0.2cm thick metal molybdenum plate substrate were weighed, sealed in a quartz capsule, and evacuated. Then the quartz tube is put into a furnace, the temperature is raised to about 550 ℃ at the heating rate of 1.0 ℃/min, and the quartz tube is cooled to the normal temperature at the speed of 0.1 ℃/min after being protected for 15 hours. Then breaking the quartz tube, taking out the substrate, and then washing the substrate with water and ethanol to prepare the red phosphorus photoelectrode.

Example 4

In this example, a crystalline phase red phosphorus photoelectrode (CP/Ti plate) of a titanium plate substrate is prepared, and the specific process is as follows:

200mg of red phosphorus and a 1.0cm wide, 3.0cm long, 0.2cm thick substrate of a metallic titanium plate were weighed, sealed in a quartz capsule, and evacuated. Then the quartz tube is put into a furnace, the temperature is raised to about 550 ℃ at the heating rate of 1.0 ℃/min, and the quartz tube is cooled to the normal temperature at the speed of 0.1 ℃/min after being protected for 15 hours. Then breaking the quartz tube, taking out the substrate, and then washing the substrate with water and ethanol to prepare the red phosphorus photoelectrode.

Comparative example 1

This example prepares an amorphous red phosphorus photoelectrode (AP/W) with a tungsten mesh substrate, and the specific process is as follows:

200mg of red phosphorus and a 1.0cm wide by 20.0cm long tungsten mesh substrate were weighed, sealed in a quartz capsule, and evacuated. Then the quartz tube is put into a furnace, the temperature is raised to about 550 ℃ at the temperature rising speed of 5.0 ℃/min, and the quartz tube is cooled to the normal temperature at the speed of 10.0 ℃/min after being protected for 15 hours. Then breaking the quartz tube, taking out the substrate, and then washing the substrate with water and ethanol to prepare the red phosphorus photoelectrode.

Comparative example 2

This example prepares an FTO conductive glass (SnO doped with fluorine)₂Conductive glass) substrate, the specific process is as follows:

200mg of red phosphorus and a 1.0cm wide by 20.0cm long FTO conductive glass substrate were weighed, sealed in a quartz capsule, and evacuated. Then the quartz tube is put into a furnace, the temperature is raised to about 550 ℃ at the temperature rising speed of 5.0 ℃/min, and the quartz tube is cooled to the normal temperature at the speed of 10.0 ℃/min after being protected for 15 hours. Then breaking the quartz tube, taking out the substrate, and then washing the substrate with water and ethanol to prepare the red phosphorus photoelectrode.

Test example 1

The experimental example tests the current-voltage relationship of the current generated by the crystalline phase red phosphorus photoelectrode (CP/W) of the tungsten mesh substrate prepared in example 1, the amorphous red phosphorus photoelectrode (AP/W) of the tungsten mesh substrate prepared in comparative example 1, and the amorphous red phosphorus photoelectrode (AP/FTO) of the FTO conductive glass substrate prepared in comparative example 2, and the specific test method of each red phosphorus photoelectrode is as follows:

the red phosphorus photoelectrode is arranged on one side of an H-shaped electrolytic cell, and a counter electrode (a platinum sheet electrode or a graphite electrode) and a reference electrode (a silver-silver chloride electrode or a saturated calomel electrode) are arranged on the other side of the H-shaped electrolytic cell. The H-type electrolytic cell is separated by a Nafion membrane. And then irradiating the red phosphorus photoelectrode by using a 300W xenon lamp, and alternately performing light treatment and non-light treatment on the red phosphorus photoelectrode by dragging and adding 0.2V-2.0V voltage to the red phosphorus photoelectrode in a period of 100s, so as to test the influence of the voltage on the amount of hydrogen generated by the electrode. The magnitude of the photocurrent may be measured by an ammeter or an electrochemical workstation. While hydrogen gas will be measured by gas chromatography (with TCD thermal conductivity detector) with shimadzu GC 2014C. The results are shown in FIG. 3.

In order to further test the influence of light on the current generated by the crystalline phase red phosphorus photoelectrode (CP/W) of the tungsten mesh substrate prepared in example 1, the amorphous red phosphorus photoelectrode (AP/W) of the tungsten mesh substrate prepared in comparative example 1, and the amorphous red phosphorus photoelectrode (AP/FTO) of the FTO conductive glass substrate prepared in comparative example 2, each red phosphorus photoelectrode was subjected to a voltage of 0.9V by the aforementioned method, and the current generated by the red phosphorus photoelectrode under light treatment and without light treatment was tested at a cycle of 100s, and the results are shown in fig. 4.

As can be seen from FIG. 3, the tungsten mesh substrate obtained in example 1 had a crystal phase red phosphorus photoelectrode generating a current of 8.0mA/cm²And is larger than many conventional metal oxide photo-anodes. When the light treatment is performed, the current generated by the photoelectrode rises, and when the light treatment is not performed, the current of the photoelectrode falls.

As can be seen from FIGS. 3-4, compared with the amorphous red phosphorus (AP/W) grown on the tungsten mesh, the performance of the crystalline phase red phosphorus (CP/W) grown on the tungsten mesh is significantly improved, which indicates that the preparation of the crystalline phase red phosphorus is the key for improving the performance. Compared with red phosphorus (AP/FTO) grown on FTO conductive glass, the red phosphorus grown on a tungsten mesh has higher performance, and the selection of a tungsten substrate and the like is the key for preparing the high-efficiency red phosphorus photoelectrode.

Test example 2

The experimental example tests the current generated by the red phosphorus photoelectrode of examples 2 to 5 under different voltages, the specific test method is the same as that of experimental example 1, and the electron microscope scan of the red phosphorus photoelectrode of examples 2 to 5 and the current generated by the counter electrode under different voltages are respectively as shown in fig. 5 to 7.

As can be seen from fig. 5 to 7, except for the tungsten mesh, tungsten, molybdenum, titanium, etc. can be used as the substrate for red phosphorus growth and good performance can be obtained. Particularly, compared with a titanium sheet, the red phosphorus photoelectrode grown on a tungsten sheet and a molybdenum sheet has better performance.

Test example 3

This test example was conducted to examine the hydrogen production capability of the tungsten mesh substrate crystalline phase red phosphorus photoelectrode (CP/W) prepared in example 1, with the red phosphorus photoelectrode as the anode and the platinum sheet counter electrode as the cathode. By connecting the reactor to a gas chromatograph with thermal conductivity detector (shimadzu GC-2014), the amount of hydrogen produced on the platinum sheet cathode can be checked.

It was examined that the amount of hydrogen generated on the platinum sheet cathode when the tungsten mesh substrate crystal phase red phosphorus photoelectrode (CP/W) prepared in example 1 was used as an anode was 1.89mL per hour.

The embodiments of the present invention have been described in detail, but the present invention is not limited to the embodiments, and various changes can be made without departing from the gist of the present invention within the knowledge of those skilled in the art. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.