CN-121974426-A - Photothermal composite material, preparation method and application thereof

Abstract

The invention relates to the technical field of photo-thermal materials, and discloses a photo-thermal composite material, a preparation method and application thereof. The photo-thermal composite material is layered composite metal hydroxide, wherein metal sulfide grows on a laminate of the layered composite metal hydroxide in situ. And dissolving the layered composite metal hydroxide, a sulfur source and a structure directing agent in a solvent, and reacting to obtain the photo-thermal composite material. The method provided by the invention is green and efficient, overcomes the tedious steps and low yield of the preparation of the photo-thermal composite material in the prior art, and improves the sunlight absorption performance, photo-thermal conversion capability and photo-thermal stability of the photo-thermal composite material by means of the interaction between the layered composite metal hydroxide and sulfide.

Inventors

• FENG YONGJUN
• MO WEIXIN
• MENG LING
• JIANG RONG

Assignees

• 北京化工大学

Dates

Publication Date

20260505

Application Date

20251226

Claims (10)

1. 1. A photo-thermal composite material is characterized by being a layered composite metal hydroxide, wherein metal sulfide grows on a laminate of the layered composite metal hydroxide in situ.
2. 2. The photothermal composite material of claim 1, wherein the metal sulfide is selected from at least one of copper sulfide, iron sulfide, and zinc sulfide, preferably copper sulfide; Preferably, the divalent metal cation in the main body laminate of the layered double hydroxide is selected from at least one of magnesium ion, copper ion and zinc ion, and the trivalent metal cation is selected from at least one of aluminum ion and iron ion; Preferably, in the photothermal composite material, the mass percentage of the metal sulfide is 2-50%, preferably 9-39%.
3. 3. A method for preparing a photothermal composite material according to claim 1 or 2, comprising dissolving a layered composite metal hydroxide, a sulfur source and a structure directing agent in a solvent, and reacting to obtain the photothermal composite material.
4. 4. The production method according to any one of claims 1 to 3, wherein the sulfur source is selected from at least one of sodium sulfide, thiourea, potassium sulfide, and carbon disulfide; Preferably, the mass of the sulfur source is 1-20%, preferably 2-5% of the mass of the layered composite metal hydroxide; Preferably, the structure directing agent is selected from at least one of polyvinylpyrrolidone, cetyltrimethylammonium bromide, sodium dodecyl sulfate, polyethylene glycol, polyethyleneimine, polyacrylic acid, sodium citrate, ethylenediamine, ammonia water, gelatin, chitosan and starch, preferably polyvinylpyrrolidone; Preferably, the polyvinylpyrrolidone has a weight average molecular weight of 2.4 to 130 g/mol, preferably 5.8 to 22 g/mol; preferably, the mass of the structure directing agent is 1-50%, preferably 1-5% of the total mass of the layered double hydroxide and the sulfur source; preferably, the solvent is water.
5. 5. The preparation method according to claim 3 or 4, wherein the temperature of the reaction is 100-250 ℃, preferably 150-200 ℃; preferably, the reaction time is from 5 to 36 hours, preferably 24 hours.
6. 6. The production method according to any one of claims 3 to 5, wherein the layered double hydroxide is produced by a coprecipitation method; preferably, the divalent metal salt used in the coprecipitation method is selected from at least one of magnesium nitrate, zinc chloride and copper chloride, and the trivalent metal salt is selected from at least one of aluminum nitrate and ferric chloride; Preferably, the alkaline solution used in the coprecipitation method is sodium hydroxide solution; Preferably, the concentration of the sodium hydroxide solution is 0.2-0.5 mol/L; Preferably, the mass ratio of both divalent metal salt and trivalent metal salt to sodium hydroxide is 2-5:1; preferably, the co-precipitation method further comprises a guest solution, the guest being selected from at least one of sodium nitrate, sodium carbonate and ammonia; preferably, the mass ratio of the guest to both the divalent metal salt and the trivalent metal salt is 1:2-5.
7. 7. The photothermal composite material prepared by the preparation method according to any one of claims 3 to 6.
8. 8. Use of the photothermal composite material according to any of claims 1-2 and 7 in the field of solar water evaporation.
9. 9. A Janus structured evaporator comprising the photothermal composite material of any of claims 1-2 and 7.
10. 10. The Janus structured evaporator of claim 9, wherein the Janus structured evaporator comprises a hydrophilic layer and a hydrophobic layer on a surface of the hydrophilic layer; Wherein the hydrophobic layer is a foam material obtained by taking the photo-thermal composite material, saccharide and polydimethylsiloxane as raw materials, mixing, drying and soaking; preferably, the saccharide is selected from at least one of glucose, chitosan and sucrose; Preferably, the hydrophilic layer is an agar layer.

Description

Photothermal composite material, preparation method and application thereof Technical Field The invention relates to the technical field of photo-thermal materials, in particular to a photo-thermal composite material and a preparation method and application thereof. Background With the continuous growth of global population and the continuous deepening of industrialization, the worldwide consumption of fresh water resources is increasing, and the fresh water resources on the earth are deficient. Therefore, the method for continuously preparing the fresh water has important practical value. The abundant sea water reserves make the sea water desalination technology an important way to solve the fresh water crisis. Among them, solar-driven photo-thermal conversion sea water desalination technology is receiving attention because of its advantages of being renewable, green, low carbon, etc. The light absorption performance, the light-heat conversion performance and the light-heat stability of the photo-thermal material are key factors for determining the solar-driven sea water desalination technology. The photo-thermal conversion materials commonly used at present include noble metal materials, carbon materials, semiconductor materials (e.g., copper sulfide, etc.), and the like. However, noble metal materials are expensive and difficult to apply on a large scale, and carbon materials have a wide absorption range, but the preparation process is complicated and the size is difficult to control. Compared with the prior art, the semiconductor material has lower cost, has the advantages of wide light absorption range and adjustable energy band structure, and has wide application in the field of solar-driven seawater desalination. However, some semiconductor materials have problems of easy agglomeration, poor stability and the like, and the light-heat conversion performance is easy to be weakened. Disclosure of Invention The invention aims to overcome the problems in the prior art and provides a photo-thermal composite material and a preparation method and application thereof. The invention adopts a coprecipitation method to obtain a layered composite metal hydroxide precursor in one step, and then utilizes the affinity of a sulfur source and metal atoms to prepare the composite material in a hydrothermal mode. In the compounding process, metal atoms and sulfur atoms in the layered composite metal hydroxide are combined through coordination bonds, so that stable compounding of materials is realized, the dispersibility of metal sulfides is improved, the absorption capacity of the metal sulfides in a near infrared band is improved, and the solar photo-thermal conversion capacity is enhanced. The material is applied to a Janus structure evaporator to realize excellent water evaporation performance. In order to achieve the above object, according to a first aspect of the present invention, there is provided a photo-thermal composite material, wherein the photo-thermal composite material is a layered composite metal hydroxide, and wherein a metal sulfide is grown in situ on a laminate of the layered composite metal hydroxide. The layered composite metal hydroxide-based photothermal composite material prepared by coordination of metal of the layered composite metal hydroxide and a sulfur source has excellent ultraviolet visible near infrared absorption performance, photothermal conversion performance and salt resistance, can be used for evaporating solar water under different salinity, and provides a green, environment-friendly, efficient and stable photothermal conversion material for solar sea water desalination. According to a second aspect of the invention, there is provided a method for preparing a photo-thermal composite material according to the first aspect, wherein the method comprises dissolving a layered composite metal hydroxide, a sulfur source and a structure directing agent in a solvent, and reacting to obtain the photo-thermal composite material. According to a third aspect of the invention, there is provided a photothermal composite material prepared according to the preparation method of the second aspect. A fourth aspect of the invention provides the use of a photothermal composite material according to the first or third aspect in the field of solar water evaporation. A fifth aspect of the present invention provides a Janus structured evaporator comprising the photo-thermal composite material of the first or third aspect. Through the technical scheme, the beneficial technical effects obtained by the invention are as follows: (1) The invention adopts an in-situ synthesis method to synthesize the layered composite metal hydroxide-based photothermal composite material with solar energy photothermal conversion performance, and in-situ prepares the layered composite metal hydroxide-based photothermal composite material on the surface of a metal laminate of the layered composite metal hydroxide and a sulfur so