阅读说明：本技术 一种碳包覆高硅氧玻璃纤维光热转换材料及其制备方法、蒸汽生成器与应用 (Carbon-coated high-silica glass fiber photothermal conversion material, preparation method thereof, steam generator and application ) 是由 岳明波 张瑛 李雯鑫 韩科玉 李宜霏 于 2021-09-17 设计创作，主要内容包括：本发明属于光热转换材料制备技术领域,具体公开一种碳包覆高硅氧玻璃纤维光热转换材料及其制备方法、蒸汽生成器与应用。所述光热转换材料由高硅氧玻璃纤布基体以及包覆在该纤维布表面的碳质层组成。所述制备方法包括如下步骤：(1)在隔氧条件下,用携带有碳质前驱体的气流吹扫高硅氧玻璃纤维,从而使碳质前驱体附着在高硅氧玻璃纤维表面,得光热转换材料前驱体。(2)在气流吹扫的同时对所述光热转换材料前驱体碳化处理,即得。本发明通过简单化学沉积的方法制备了碳材料包覆的高硅氧纤维光热转换材料,氧化硅和碳复合材料不但表现出对酸、碱以及生物污染的高稳定性,同时具有良好的水蒸发性能,拓宽了光热盐水淡化以及污水淡化的使用范围。(The invention belongs to the technical field of preparation of photo-thermal conversion materials, and particularly discloses a carbon-coated high-silica glass fiber photo-thermal conversion material, a preparation method thereof, a steam generator and application. The photo-thermal conversion material consists of a high silica glass fiber cloth matrix and a carbon layer coated on the surface of the fiber cloth. The preparation method comprises the following steps: (1) and under the condition of oxygen isolation, blowing the high silica glass fiber by using gas flow carrying the carbonaceous precursor, so that the carbonaceous precursor is attached to the surface of the high silica glass fiber, and obtaining the photo-thermal conversion material precursor. (2) And carbonizing the photo-thermal conversion material precursor while blowing the gas flow to obtain the photo-thermal conversion material. The high silica fiber photothermal conversion material coated by the carbon material is prepared by a simple chemical deposition method, and the silicon oxide and carbon composite material not only shows high stability to acid, alkali and biological pollution, but also has good water evaporation performance, so that the application range of photothermal brine desalination and sewage desalination is widened.)

1. A carbon-coated high silica glass fiber photothermal conversion material is characterized by comprising a high silica glass fiber matrix and a carbon layer coated on the surface of the matrix.

2. The carbon-coated high silica glass fiber photothermal conversion material according to claim 1, wherein the substrate is a fiber cloth woven from high silica glass fibers, and the carbon layer covers the surface of the fiber cloth to form a flexible planar photothermal conversion material.

3. The carbon-coated high silica glass fiber photothermal conversion material according to claim 2, wherein the fiber cloth has a thickness of 0.06-3 mm, preferably the high silica glass fiber has a silica content >92 wt%.

4. The carbon-coated high silica glass fiber photothermal conversion material according to claim 2 or 3, wherein the weaving type of the fiber cloth includes any one of two-dimensional plain weave, two-dimensional twill weave, two-dimensional satin weave, and the like; preferably, the number of the strands of the high silica glass fiber bundle is 1K-12K.

5. A preparation method of a carbon-coated high silica glass fiber photothermal conversion material is characterized by comprising the following steps:

(1) under the condition of oxygen isolation, blowing the high silica glass fiber by using gas flow carrying a carbonaceous precursor, so that the carbonaceous precursor is attached to the surface of the high silica glass fiber, and obtaining a photo-thermal conversion material precursor;

(2) and carbonizing the photo-thermal conversion material precursor while blowing the gas flow to obtain the photo-thermal conversion material.

6. The method for preparing the carbon-coated high-silica glass fiber photothermal conversion material according to claim 5, wherein in step (1), the carbonaceous precursor comprises an aromatic polymer, preferably, the aromatic polymer comprises at least one of styrene, polystyrene, polyvinylimidazole, and vinylimidazole copolymer;

preferably, in step (1), the gas stream comprises any one of nitrogen and inert gas, and the high silica glass fiber is located in the oxygen-barrier condition created by the gas stream;

preferably, in step (1), the purging process is: the gas flow rate is 5-30 mL/min, and the carbonization treatment is finished after purging.

7. The method for preparing a carbon-coated high silica glass fiber photothermal conversion material according to claim 6, wherein in the step (2), the temperature of the carbonization treatment is 600-1000 ℃ and the time is 1-20 hours;

preferably, the carbonization treatment is carried out at the gas flow purge rate of 5 to 30 mL/min.

8. A steam generator comprising a flotation layer, a water absorbing layer and a light-to-heat conversion layer; wherein: the water absorbing layer is fixed on the floating layer, the water absorbing layer at least extends to the lower surface of the floating layer, the light-to-heat conversion layer is fixed on the water absorbing layer, and the material of the light-to-heat conversion layer is the carbon-coated high silica glass fiber light-to-heat conversion material as defined in any one of claims 1 to 4 or the carbon-coated high silica glass fiber light-to-heat conversion material prepared by the method as defined in any one of claims 5 to 7.

9. A steam generator as claimed in claim 8, wherein the material of the buoyant layer comprises any one of foam, hydrophobic wood block, hollow plastic; or the water absorption layer comprises any one of non-woven fabrics, sponge and polyvinyl alcohol.

10. Use of the carbon-coated high silica glass fiber photothermal conversion material of any one of claims 1 to 4 or the carbon-coated high silica glass fiber photothermal conversion material prepared by the method of any one of claims 5 to 7 or the steam generator of claim 8 in the field of ocean engineering.

Technical Field

The invention belongs to the technical field of preparation of photo-thermal conversion materials, and particularly relates to a carbon-coated high-silica glass fiber photo-thermal conversion material, a preparation method thereof, a steam generator and application.

Background

The information in this background section is disclosed to enhance understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms part of the prior art already known to a person of ordinary skill in the art.

The shortage of fresh water is one of the problems that human society, particularly developing countries and remote areas, needs to be urgently solved. Seawater desalination is one of the strategies for solving the shortage of fresh water in the countries near the sea and islands. Up to now, various methods such as reverse osmosis filtration, membrane evaporation and the like have been applied to seawater desalination. Recently, the development and utilization of solar energy for green seawater desalination with low energy consumption becomes a research hotspot. The solar light is effectively converted into heat energy through the photo-thermal material, and seawater is condensed into liquid to prepare fresh water after being evaporated. For example, patent publication No. CN111336699B discloses a flax fiber-based photothermal conversion material prepared by weaving flax fibers into a net-like structure, followed by dispersion spraying of candle ash and polyurethane.

To date, various materials have been developed as photothermal conversion materials for solar steam power generation, such as carbon-based materials, metal nanoparticles, aerogels, and porous polymers. The research on photothermal conversion materials has mainly focused on the following aspects: first, the broadband solar spectrum absorbs, achieving high solar-thermal conversion efficiency. Second, localized heating in the evaporation zone is possible, minimizing heat loss. Third, water is allowed to continue to be supplied by capillary effect to achieve continuous evaporation. It is emphasized that, in addition to high photothermal conversion performance, the stability and wide applicability of photothermal conversion materials are essential for such materials to actually realize industrial applications. However, the existing photothermal conversion materials still have the following problems: for example, carbon materials have high stability, but carbon materials have poor mechanical properties. And the organic polymer polypyrrole, polyaniline and other materials have poor biological pollution resistance. Metal-based materials are susceptible to corrosion in high salinity waters.

Disclosure of Invention

Aiming at the problems, the improvement of the stability and mechanical strength of the photothermal conversion material, such as corrosion resistance of strong acid and strong base, erosion resistance of high-salinity solution, biological pollution resistance, tensile strength and friction resistance of the material, and the like, is a problem which needs to be solved for really realizing industrial application of the photothermal conversion material. In order to achieve the purpose, the invention provides a carbon-coated high silica glass fiber photothermal conversion material, a preparation method thereof, a steam generator and application, and the specific technical scheme is as follows:

in a first aspect of the present invention, a carbon-coated high silica glass fiber photothermal conversion material is provided, which includes a high silica glass fiber substrate and a carbonaceous layer coated on a surface of the substrate.

Further, the matrix is fiber cloth woven by high silica glass fibers, and the carbon layer covers the surface of the fiber cloth to form the flexible planar photothermal conversion material.

Further, the thickness of the fiber cloth is 0.06-3 mm, and preferably, the silicon oxide content of the high-silica glass fiber is more than 92 wt%.

Further, the weaving type of the fiber cloth includes any one of two-dimensional plain weave, two-dimensional twill weave, two-dimensional satin weave, and the like.

Furthermore, the number of the strands of the high silica glass fiber bundle is selectable between 1K and 12K, such as any one of 1K, 3K, 6K, 12K and the like.

In a second aspect of the present invention, a method for preparing a carbon-coated high silica glass fiber photothermal conversion material is provided, which comprises the following steps:

(1) and under the condition of oxygen isolation, blowing the high silica glass fiber by using gas flow carrying the carbonaceous precursor, so that the carbonaceous precursor is attached to the surface of the high silica glass fiber, and obtaining the photo-thermal conversion material precursor.

(2) And carrying out carbonization treatment on the photo-thermal conversion material precursor while blowing the gas flow to obtain the photo-thermal conversion material.

Further, in the step (1), the carbonaceous precursor includes an aromatic polymer, and preferably, the aromatic polymer includes at least one of styrene, polystyrene, polyvinylimidazole, vinylimidazole copolymer, and the like. The aromatic polymers have low decomposition temperature, are volatilized into gaseous substances after being heated, and can be uniformly attached to the surface of the high silica glass fiber after being blown by air flow.

Further, in step (1), the gas stream comprises any one of nitrogen, inert gas and the like, and the high silica glass fiber is positioned in the gas stream, so that oxygen-isolating conditions are simultaneously created.

Further, in the step (1), the purging process comprises the following steps: the gas flow rate is 5-30 mL/min, and the carbonization treatment is finished after purging.

Further, in the step (2), the carbonization treatment is carried out under the condition of the air flow purging rate of 5-30 mL/min.

Further, in the step (2), the temperature of the carbonization treatment is 600-1000 ℃ and the time is 1-20 hours. After high-temperature roasting, the carbonaceous precursor attached to the surface of the high silica glass fiber forms a carbonaceous layer, namely the carbon-coated high silica glass fiber photothermal conversion material.

In a third aspect of the invention, a steam generator is provided that includes a flotation layer, a water absorbing layer, and a light-to-heat conversion layer. Wherein: the water absorbing layer is fixed on the floating layer and at least extends to the lower surface of the floating layer, the light-heat conversion layer is fixed on the water absorbing layer, and the material of the light-heat conversion layer is the carbon-coated high silica glass fiber light-heat conversion material provided by the invention.

Furthermore, the material of the floating layer comprises any one of foam, hydrophobic wood blocks, hollow plastic and the like, and the floating layer is mainly used as a load to float the water layer and the light-heat conversion layer on the water surface to be desalinated.

Further, the water-absorbing layer includes any one of a non-woven fabric, a sponge, polyvinyl alcohol, and the like. The water absorbing layer has the main function of absorbing water to be desalinated to the light-heat conversion layer, and then the water is evaporated by utilizing heat generated by the light-heat conversion layer, so that the water is desalinated.

In the fourth aspect of the invention, the carbon-coated high silica glass fiber photothermal conversion material and the steam generator are applied to the field of ocean engineering and the like, for example, the material is made into a seawater desalination device for seawater desalination.

Compared with the prior art, the invention has the following beneficial effects:

(1) the high silica fiber photothermal conversion material coated by the carbon material is prepared by a simple chemical deposition method, and the silicon oxide and carbon composite material not only shows high stability to acid, alkali and biological pollution, but also has good water evaporation performance, so that the application range of photothermal brine desalination and sewage desalination is widened.

(2) The silica glass fiber mainly contains high-oxygen Silicon (SiO)₂) It has high thermal stability (continuous temperature resistance up to 1000 ℃) and chemical stability (excellent salt water corrosion resistance and biological pollution resistance); meanwhile, the high silica fiber cloth has very strong tensile strength and friction resistance. And the carbon also has high salt water corrosion resistance and biological pollution resistance, and meanwhile, the carbon has strong light absorption and has high solar-thermal conversion efficiency. Therefore, after the silica glass fiber and the carbon material are combined, the mechanical strength advantage of the matrix and the high-efficiency solar-thermal conversion efficiency of the carbon coating layer can be effectively exerted, and the composite material with high stability, mechanical strength and photo-thermal conversion efficiency is obtained.

(3) According to the invention, after the carbon layer is coated on the silica glass fiber, the problem that the light absorption is influenced by strong light reflection capability caused by white high silica glass material is effectively solved, because the carbon layer coated on the silica glass fiber is black, the carbon layer can more effectively absorb solar light compared with other colors, and the solar-thermal conversion efficiency is promoted.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. Embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:

fig. 1 is a graph showing the effects of the high silica glass fiber cloth used in the first embodiment and the carbon-coated high silica glass fiber photothermal conversion material prepared based on the same.

Fig. 2 is an EDS spectrum and an element distribution diagram of the carbon-coated high silica glass fiber photothermal conversion material prepared in the first example.

Fig. 3 is SEM images of carbon-coated high silica glass fiber photothermal conversion materials prepared in the first example at different magnification.

Fig. 4 is a graph showing the absorption curve of the uv-vis-nir spectrum of the carbon-coated high-silica glass fiber photothermal conversion material prepared in the first example.

FIG. 5 is a stress-strain curve of the carbon-coated high silica glass fiber photothermal conversion material prepared in the first example.

Fig. 6 is a schematic structural view of a steam generator used in the seawater evaporation efficiency test of the following example, in which 1 denotes a floating layer, 2 denotes a water absorbing layer, and 3 denotes a photothermal conversion layer.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out according to conventional conditions or according to conditions recommended by the manufacturers.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The reagents or starting materials used in the present invention can be purchased from conventional sources, and unless otherwise specified, the reagents or starting materials used in the present invention can be used in a conventional manner in the art or in accordance with the product specifications.

In addition, any methods and materials similar or equivalent to those described herein can be used in the methods of the present invention. The preferred methods and materials described in this invention are exemplary only. The invention will now be further described with reference to the drawings and specific examples in the specification.

First embodiment

The preparation method of the carbon-coated high silica glass fiber photothermal conversion material comprises the following steps:

(1) high silica glass fiber cloth of the following specifications was prepared: the thickness was 2mm and the silica content was 96 wt%. The fiber cloth is formed by two-dimensional plain weaving of 3K high silica glass fiber bundles, and the length and the width of the fiber cloth are both 10cm for standby.

(2) Putting 3g of polyvinyl imidazole in a high silica boat, and then putting the boat in a vacuum high silica tube (roasting furnace) with the diameter of 60 mm; placing the high silica glass fiber cloth beside a high silica boat in a high silica tube, sealing two ends of the high silica glass fiber cloth, introducing nitrogen, blowing at the room temperature for 30 minutes at the flow rate of 30mL/min, blowing air clean, adjusting the gas flow rate to 10mL/min, heating to 800 ℃ at the rate of 10 ℃/min, preserving heat at the temperature for 2 hours for carbonization, and cooling to the room temperature in nitrogen airflow after the carbonization treatment is completed.

(3) And (3) washing the product obtained after the carbonization treatment in the step (2) with clear water, removing residual substances on the surface, and drying at 100 ℃ to constant weight to obtain the carbon-coated high silica glass fiber cloth.

As shown in fig. 1, which is a graph showing the effect of the high silica glass fiber cloth used in the first embodiment and the carbon-coated high silica glass fiber photothermal conversion material prepared based on the high silica glass fiber cloth, it can be seen that the surface of a single fiber of the original glass fiber is smooth, the diameter is about 10 μm, the woven fiber cloth is white, and the sample turns black after carbon coating, which indicates that a carbon layer is successfully coated on the surface of the fiber cloth.

As shown in fig. 2, which is an EDS spectrum and an element distribution diagram of the carbon-coated high silica glass fiber photothermal conversion material prepared in the first example, it can be seen that the photothermal conversion material contains high silica and carbon as main components, and in addition, contains about 3% of nitrogen element from polyvinylimidazole.

As shown in fig. 3, which is an SEM image of the carbon-coated high silica glass fiber photothermal conversion material prepared in the first example at different magnification, it can be seen that the photothermal conversion material is in a fiber shape.

Light absorption property test: the carbon-coated high silica glass fiber photothermal conversion material prepared in the first embodiment is cut into a square with the side length of 2cm, and the ultraviolet visible near-infrared spectrometer is used for testing the light absorption performance, wherein the light wavelength is 200-2500 nm. The test results are shown in fig. 4. It can be seen that the light absorption rate of the photothermal conversion material reaches 94%, and the photothermal conversion material has good light absorption performance. The tensile strength of the sample was measured using a tensile tester, and the results are shown in fig. 5. It can be seen that after the fibers are coated with carbon, the stress of the material still exceeds 200 MPa, and the tensile strength is close to that of metal and excellent. Further, the carbon layer on the surface of the fiber cloth did not come off after the tensile deformation, indicating that the bonding performance between the carbon layer and the fiber substrate was excellent.

And (3) testing the evaporation performance: first, referring to fig. 6, a steam generator was prepared using the carbon-coated high silica glass fiber photothermal conversion material prepared in each example. The steam generator includes a polystyrene foam floating layer, a non-woven fabric (55% cellulose and 45% polyester fiber) water absorbing layer, and a light-to-heat conversion layer. Wherein: the layer that absorbs water is fixed on the floating layer, and the layer that absorbs water extends to the lower surface department on floating layer at least, light-to-heat conversion layer fixes on the layer that absorbs water. The steam generator was then tested for evaporation performance in simulated seawater at different salt concentrations (3.5 wt%, 7wt%, 15wt%, 30wt% sodium chloride concentration, respectively).

Firstly, placing simulated seawater in an open container, then placing a steam generator in the simulated seawater, simulating a solar light source by using a xenon lamp to irradiate (1 solar light intensity), and recording the container and the steam generator by using an electronic balanceThe water weight change over 8 hours and was recorded every 5 minutes, and the evaporation performance of the evaporator was examined. The results show that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.24 kg.m^-2·h^-1、1.19 kg·m^-2·h^-1、1.15 kg·m^-2·h^-1And 1.01 kg m^-2·h^-1。

Second embodiment

The preparation method of the carbon-coated high silica glass fiber photothermal conversion material comprises the following steps:

(1) high silica glass fiber cloth of the same specification as that of the first example was prepared and set aside.

(2) Placing 2g of polystyrene in a high silica boat, and then placing the high silica boat in a vacuum high silica tube (roasting furnace) with the diameter of 60 mm; placing the high silica glass fiber cloth beside a high silica boat in a high silica tube, sealing two ends of the high silica glass fiber cloth, introducing nitrogen, blowing at the room temperature for 30 minutes at the flow rate of 30mL/min, blowing air clean, adjusting the gas flow rate to 5mL/min, heating to 900 ℃ at the speed of 10 ℃/min, preserving heat at the temperature for 3 hours for carbonization, and cooling to the room temperature in nitrogen airflow after the carbonization treatment is completed.

(3) And (3) washing the product obtained after the carbonization treatment in the step (2) with clear water, removing residual substances on the surface, and drying at 100 ℃ to constant weight to obtain the carbon-coated high silica glass fiber cloth photo-thermal conversion material.

Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test at a solar intensity of 0.8, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.05 kg.m^-2·h^-1、1.01 kg·m^-2·h^-1、0.94 kg·m^-2·h^-1And 0.88 kg · m^-2·h^-1。

Third embodiment

The preparation method of the carbon-coated high silica glass fiber photothermal conversion material comprises the following steps:

(1) high silica glass fiber cloth of the same specification as that of the first example was prepared and set aside.

(2) Taking 2g of the copolymer of styrene and vinyl imidazole, placing the copolymer in a high silica boat, and then placing the boat in a vacuum high silica tube (roasting furnace) with the diameter of 60 mm; placing the high silica glass fiber cloth beside a high silica boat in a high silica tube, sealing two ends of the high silica glass fiber cloth, introducing nitrogen, blowing at room temperature for 30 minutes at a flow rate of 40mL/min, blowing air clean, adjusting the flow rate of the air to 10mL/min, heating to 800 ℃ at a rate of 10 ℃/min, preserving heat at the temperature for 6 hours to perform carbonization treatment, and cooling to room temperature in nitrogen airflow after the carbonization treatment is completed.

(3) And (3) washing the product obtained after the carbonization treatment in the step (2) with clear water, removing residual substances on the surface, and drying at 100 ℃ to constant weight to obtain the carbon-coated high silica glass fiber cloth photo-thermal conversion material.

Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test under a light intensity of 1.5 sunlight, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.51 kg.m^-2·h^-1、1.45 kg·m^-2·h^-1、1.35 kg·m^-2·h^-1And 1.30 kg m^-2·h^-1。

Fourth embodiment

The carbon-coated high silica glass fiber cloth photothermal conversion material prepared in the first example was completely immersed in a beaker filled with 1M hydrochloric acid, then the beaker was placed in a polytetrafluoroethylene autoclave, hydrothermal treatment was carried out at 100 ℃ for 24 hours, after completion, the photothermal conversion material was taken out, washed with water, dried, and tested for water evaporation performance of the photothermal conversion material under 1 sun intensity.

Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test under 1 solar intensity, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.17 kg.m^-2·h^-1、1.12 kg·m^-2·h^-1、1.09 kg·m^-2·h^-1And 0.97 kg m^-2·h^-1。

Fifth embodiment

The carbon-coated high silica glass fiber cloth photothermal conversion material prepared in the second example was completely immersed in a beaker filled with 1M sodium hydroxide, then the beaker was placed in a polytetrafluoroethylene autoclave, hydrothermal treatment was carried out at 100 ℃ for 24 hours, after completion, the photothermal conversion material was taken out, washed with water, dried, and tested for water evaporation performance of the photothermal conversion material under 0.8 suns.

Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test at a solar intensity of 0.8, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.02 kg.m^-2·h^-1、0.92 kg·m^-2·h^-1、0.85 kg·m^-2·h^-1And 0.81 kg m^-2·h^-1。

Sixth embodiment

The carbon-coated high silica glass fiber cloth photo-thermal conversion material prepared in the third embodiment is completely immersed in natural pond water full of moss, then placed outdoors for 30 days, then taken out of the thermal conversion material for washing and drying, and the water evaporation performance of the thermal conversion material under the intensity of 1.5 suns is tested.

Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test under a light intensity of 1.5 sunlight, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.41 kg.m^-2·h^-1、1.35 kg·m^-2·h^-1、1.31 kg·m^-2·h^-1And 1.25 kg m^-2·h^-1。

Seventh embodiment

The preparation method of the carbon-coated high silica glass fiber photothermal conversion material comprises the following steps:

(1) high silica glass fiber cloth of the following specifications was prepared: the thickness was 3mm and the silica content was 92 wt%. The fiber cloth is formed by weaving 12K high silica glass fiber bundles in a two-dimensional twill mode, and the length and the width of the fiber cloth are both 10cm for later use.

(2) Putting 3g of polystyrene into a high silica boat, and then putting the high silica boat into a vacuum high silica tube (roasting furnace) with the diameter of 60 mm; placing the high silica glass fiber cloth beside a high silica boat in a high silica tube, sealing two ends of the high silica glass fiber cloth, introducing argon, blowing at the room temperature for 30 minutes at the flow rate of 20mL/min, blowing air clean, adjusting the gas flow rate to 10mL/min, heating to 1000 ℃ at the rate of 20 ℃/min, preserving heat at the temperature for 1 hour for carbonization, and cooling to the room temperature in nitrogen gas flow after the carbonization treatment is finished. Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test under 1 solar intensity, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 1.21 kg.m^-2·h^-1、1.18 kg·m^-2·h^-1、1.06 kg·m^-2·h^-1And 0.95 kg · m^-2·h^-1。

Eighth embodiment

The preparation method of the carbon-coated high silica glass fiber photothermal conversion material comprises the following steps:

(1) high silica glass fiber cloth of the following specifications was prepared: the thickness is 0.06mm, and the silicon oxide content is 98 wt%. The fiber cloth is woven by two-dimensional satin weaves of 1K high silica glass fiber bundles, and the length and the width of the fiber cloth are both 10cm for standby.

(2) Putting 3g of styrene into a high silica boat, and then putting the high silica boat into a vacuum high silica tube (roasting furnace) with the diameter of 60 mm; placing the high silica glass fiber cloth beside a high silica boat in a high silica tube, sealing two ends of the high silica glass fiber cloth, introducing argon, blowing at the room temperature for 30 minutes at the flow rate of 30mL/min, blowing air clean, adjusting the gas flow rate to 10mL/min, heating to 600 ℃ at the rate of 10 ℃/min, preserving heat at the temperature for 20 hours for carbonization, and cooling to the room temperature in nitrogen gas flow after the carbonization treatment is finished. Referring to the method of the first example, the light prepared in this example was illuminated at 1 solar intensityThe heat conversion material is subjected to an evaporation performance test, and the result shows that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 0.94 kg.m^-2·h^-1、0.86 kg·m^-2·h^-1、0.75 kg·m^-2·h^-1And 0.72 kg · m^-2·h^-1。

Ninth embodiment

High silica glass fiber cloth without carbonization is taken as a photo-thermal conversion reference material. High silica glass fiber cloth: the thickness is 0.06mm, and the silicon oxide content is 98 wt%. The fiber cloth is woven by two-dimensional satin weaves of 1K high silica glass fiber bundles, and the length and the width of the fiber cloth are both 10cm for standby.

Referring to the method of the first example, the photothermal conversion material prepared in this example was subjected to an evaporation performance test under 1 solar intensity, and the results showed that: in the simulated seawater of the four concentrations, the average evaporation rate in 8 hours is 0.15 kg.m^-2·h^-1、0.13 kg·m^-2·h^-1、0.14 kg·m^-2·h^-1And 0.12 kg · m^-2·h^-1. Without adding any photo-thermal conversion material, the light source is directly irradiated on the water surface under the same condition, and the average evaporation rate of 8 hours is 0.17 kg.m^-2·h^-1、0.16 kg·m^-2·h^-1、0.18 kg·m^-2·h^-1And 0.15 kg · m^-2·h^-1。

It can be seen that the evaporation performance of the unmodified high silica glass fiber cloth material is much lower than that of the first to eighth embodiments.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.