Preparation method of six-membered high-entropy monatomic nitrogen-rich porous photothermal material

Abstract

The application discloses a preparation method of six-element high-entropy single-atom nitrogen-rich porous photothermal material. In the solvent-free condition, 1h-123-triazole is introduced as one of raw materials, a six-element high-entropy single-atom nitrogen-rich photothermal material precursor is prepared through a mechanical ball milling method, then the six-element high-entropy single-atom nitrogen-rich photothermal material is obtained through washing, centrifugation, high-temperature annealing reaction and cooling at room temperature. The six-element high-entropy single-atom nitrogen-rich photothermal material precursor is obtained through an in-situ mechanical chemical preparation method, and 1h-123-triazole is added, so that nitrogen-nitrogen "explosion" caused by nitrogen-nitrogen double bond is generated in the later annealing process, and then the photothermal material with high porosity and high stability is obtained. The application is an effective method for preparing the porous photothermal material, which is simple and convenient in operation, green and safe, good in repeatability and high in efficiency.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of porous photothermal materials, and particularly relates to a preparation method of a six-element high-entropy single-atom nitrogen-rich porous photothermal material. BACKGROUND

[0002] With the increasing development of science and technology, interface solar water evaporation as a new generation of seawater desalination and wastewater treatment technology has the characteristics of high photo-thermal conversion efficiency, simple operation and environmental friendliness. Carbon-based materials have excellent broadband absorption and high photo-thermal conductivity, and become excellent materials in future interface solar water evaporation. MOFs (metal-organic framework materials) are a kind of crystalline porous materials with periodic network, which are connected by self-assembly of metal ions or metal clusters and bridged organic ligands. MOF can provide rich carbon source and realize doping of metal nanometer ions in carbon pore channel. High-entropy alloy: high-entropy alloy is a single-phase solid solution alloy containing five or more metals, and each metal is formed in a near-equal or equal atomic ratio. High-entropy alloy has been widely concerned in many fields in recent years due to its unique thermal, electrical, magnetic and mechanical properties. At the same time, the concept of high entropy has been extended to ceramics, catalysis, MOF, photothermal and other aspects. On this basis, high-entropy single atoms are introduced, which are loaded in MOF through coordination, and after heat treatment, a carbon-based porous structure photothermal material with high-entropy single atoms is obtained, which is applied to seawater evaporation.

[0003] At present, the preparation steps of the photothermal material are relatively complicated, the cost is high, and some materials need to add organic solvents, which does not achieve the purpose of simplicity and green. The present experiment improves the above two points, and adopts an environmentally friendly, simple and controllable mechanical chemical preparation process to prepare the photothermal material. SUMMARY

[0004] The purpose of the present application is to provide a preparation method of a six-element high-entropy single-atom nitrogen-rich porous photothermal material, which solves the problem of using organic solvents in the synthesis process of the existing photothermal material. The synthesis method is more simplified and green and safe.

[0005] The technical scheme adopted by the present application is a preparation method of a six-element high-entropy single-atom nitrogen-rich porous photothermal material, and the specific operation steps are as follows:

[0006] Step 1, mechanically preparing a six-membered high-entropy single-atom nitrogen-rich photothermal material precursor: 1h-123-triazole, zinc chloride, basic chromium sulfate, manganese sulfate, iron chloride, cobalt acetate, nickel chloride and copper acetate powders are mixed in a certain molar ratio, put into a Retsch high-throughput tissue mill MM400 rotary ball mill (sample to ball mass ratio is 2:1), start the ball mill, set the ball milling time to 150-210 min, set the frequency to 30 Hz, until the solid reactants become a paste-like slurry A;

[0007] Step 2, separate the paste-like slurry A from the stainless steel balls, and transfer the paste-like slurry A into a centrifuge tube, and put it into a centrifuge to remove excess 1h-123-triazole, set the centrifuge to 6000r / min for 2-3 min, and obtain product B;

[0008] Step 3, put product B into an oven at 60-80℃ for 12-15h drying, and grind it with a mortar to obtain a six-membered high-entropy single-atom nitrogen-rich photothermal material precursor, i.e. product C.

[0009] Step 4, place product C in a porcelain boat, heat to 900-1000℃ at a heating rate of 5-10℃ / min in a program-controlled tube furnace under N2 atmosphere protection, keep the temperature for 2 hours, and then naturally cool to room temperature to obtain a six-membered high-entropy single-atom nitrogen-rich photothermal material, i.e. powder D.

[0010] Step 5, the prepared photothermal material is assembled with different types of polymers / cellulose substrates, etc. into a photothermal water evaporator for actual water body desalination.

[0011] The application also has the characteristics of,

[0012] The molar ratio of 1h-123-triazole, zinc chloride, basic chromium sulfate, manganese sulfate, iron chloride, cobalt acetate, nickel chloride and copper acetate in step 1 is 400:100:0.1:0.1:0.1:0.1:0.1:0.1

[0013] The mechanical ball milling time in step 1 is set to 150-210 min, and the ball milling jar with an inner diameter of 1.8 cm and a diameter of 0.8 cm is selected.

[0014] In step 1, the basic chromium sulfate, manganese sulfate, iron chloride, cobalt acetate, nickel chloride and copper acetate can be replaced by any one of chloride salt, acetate salt and sulfate salt.

[0015] The drying temperature in step 3 is 60-80℃, and the time is 12-24 hours.

[0016] The annealing process in step 4 is carried out in an inert atmosphere, the temperature is set to 900-1000 DEG C, and the holding time should be 2 hours.

[0017] The heating rate in step 4 is 5-10 DEG C / min.

[0018] In step 5, the photothermal material is assembled into a photothermal water evaporator with different types of polymer / cellulose substrates and the like at a certain addition amount, and is used for seawater desalination of actual water bodies.

[0019] The present application adopts a simple, green and solvent-free mechanochemical synthesis method to prepare a six-membered high-entropy single-atom nitrogen-rich photothermal material in situ, and 1h-123-triazole is added during the preparation process, and the morphology and performance of the product are regulated by the "explosion" generated by the cleavage of the nitrogen-nitrogen double bond at 400 DEG C, the sample has the characteristics of low metal loading, low density, ultra-light, low price and high performance, the pores in the porous structure provide rich paths for the absorption of sunlight, and an ideal light-heat absorption material is obtained.

[0020] The present application has the following beneficial effects:

[0021] (1) The present application adopts an environmentally friendly, simple and controllable mechanochemical preparation process, directly adds raw materials and mechanically ball-mills to synthesize a six-membered high-entropy single-atom nitrogen-rich photothermal material precursor, and no organic solvent is used in the process. At the same time, 1h-123-triazole is introduced as one of the raw materials in the process, and the nitrogen-nitrogen double bond of 1h-123-triazole will "explode" during the 400 DEG C heat treatment process, thereby producing a porous structure, and a high-porosity six-membered high-entropy single-atom nitrogen-rich photothermal material is obtained.

[0022] (2) The porous photothermal material prepared in the present application shows excellent light-heat conversion performance under xenon lamp irradiation. The xenon lamp is adjusted to a sunlight intensity and irradiated for 1h, and the photothermal material reaches a maximum temperature of 90 DEG C. And the absorbance of the sample also reaches 95%, indicating that the sample has excellent light absorption degree.

[0023] (3) The present application can realize the component regulation of high-entropy single-atom particles by controlling different types of metal salts, and the method can also be applied to other metal salts, which is an extended synthesis strategy.

[0024] (4) The photothermal material is assembled into a photothermal water evaporator with different types of polymer / cellulose substrates and the like at a certain addition amount, and is used for seawater desalination of actual water bodies. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a flow chart of the preparation method of the six-membered high-entropy single-atom nitrogen-rich porous photothermal material of the present application;

[0026] Figure 2is the XRD diffraction pattern of the precursor (product C) in the application;

[0027] Figure 3 is the SEM image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material in the application.

[0028] Figure 4 is the surface infrared image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material in the application under irradiation of a solar light intensity for 1 hour;

[0029] Figure 5 is the temperature curve image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material in the application under irradiation of a solar light intensity for 1 hour;

[0030] Figure 6 is the absorption rate image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material in the application in the ultraviolet-visible-near infrared region;

[0031] Figure 7 is the cycle image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material in the application under 8 times of irradiation of a solar light intensity. DETAILED DESCRIPTION

[0032] The purpose of the application is to introduce a six-element high-entropy single atom during the synthesis of high-energy MOF to obtain a six-element high-entropy single-atom nitrogen-rich photothermal material precursor. The method uses mechanical synthesis to reduce the use of organic solvents in the preparation process of MOFs, and introduces 1h-123-triazole. Through heat treatment of the sample, the nitrogen-nitrogen "explosion" of the nitrogen-nitrogen double bond of the high-energy MOF effectively improves the porosity of the target material. Through calcination treatment, a six-element high-entropy single-atom nitrogen-rich photothermal material is finally obtained.

[0033] The application will be further described below in conjunction with specific examples.

[0034] Example 1

[0035] The preparation method of the six-element high-entropy single-atom nitrogen-rich porous photothermal material in the application is as shown in Figure 1 The specific operation steps are as follows:

[0036] Step 1, mix 1h-123-triazole, zinc chloride, basic chromium sulfate, manganese sulfate, iron chloride, cobalt acetate, nickel chloride and copper acetate uniformly in a molar ratio of 400:100:0.1:0.1:0.1:0.1:0.1:0.1, and put them into a Retsch Leyci high-throughput tissue mill MM400 rotary ball mill. Select a ball mill tank with an inner diameter of 1.8 cm and a capacity of 5 ml, and stainless steel grinding balls with a diameter of 0.8 cm (the mass ratio of the sample to the grinding balls is 2:1). Start the ball mill, set the ball milling time to 150 minutes, and the frequency to 30 Hz, until the solid reactants become a paste-like slurry A;

[0037] Step 2, separate the paste slurry A from the stainless steel balls, and transfer the paste slurry A into a centrifuge tube, and put it into a centrifuge for centrifugation (remove excess 1h-123-triazole), the centrifuge is set to 6000r / min, time 3min, to obtain product B;

[0038] Step 3, put product B into an oven at 80℃ for 12h drying, and grind it with a mortar to obtain product C.

[0039] Step 4, place product C into a porcelain boat, and place it in a program-controlled tube furnace under N2 atmosphere protection, heat to 900℃ at a heating rate of 5℃ / min, keep for 2 hours, and then naturally cool to room temperature to obtain black powder D.

[0040] Step 5, assemble the photothermal material with different types of polymer / cellulose and other substrates into a photothermal water evaporator according to a certain amount of addition, and use it for actual water body desalination.

[0041] Example 2

[0042] The preparation method of the six-element high-entropy single-atom nitrogen-rich porous photothermal material of the present application is as shown in Figure 1 , and the specific operation steps are as follows:

[0043] Step 1, mix 1h-123-triazole, zinc chloride, chromium sulfate, manganese sulfate, iron chloride, cobalt acetate, nickel sulfate and copper acetate uniformly according to a molar ratio of 400:100:0.1:0.1:0.1:0.1:0.1:0.1, and put them into a Retsch Leyci high-throughput tissue instrument MM400 rotary ball mill, select a ball mill tank with an inner diameter of 1.8cm and a capacity of 5ml, and stainless steel balls with a diameter of 0.8cm (sample to ball mass ratio of 2:1), start the ball milling, set the ball milling time to 180 minutes, and the frequency to 30Hz, until the solid reactants become paste slurry A;

[0044] Step 2, separate the paste slurry A from the stainless steel balls, and transfer the paste slurry A into a centrifuge tube, and put it into a centrifuge for centrifugation (remove excess 1h-123-triazole), the centrifuge is set to 6000r / min, time 3min, to obtain product B;

[0045] Step 3, put product B into an oven at 70℃ for 15h drying, and grind it with a mortar to obtain product C.

[0046] Step 4, place product C into a porcelain boat, and place it in a program-controlled tube furnace under N2 atmosphere protection, heat to 1000℃ at a heating rate of 10℃ / min, keep for 2 hours, and then naturally cool to room temperature to obtain the nitrogen-rich porous photothermal material, i.e. black powder D.

[0047] Step 5, assemble the photothermal water evaporator with the photothermal material and different types of polymer / cellulose substrate, etc. in a certain amount, for seawater desalination of actual water bodies.

[0048] Example 3

[0049] The preparation method of the six-element high-entropy single-atom nitrogen-rich porous photothermal material of the application is as follows:

[0050] Step 1, mix 1h-123-triazole, zinc chloride, chromium chloride, manganese sulfate, iron chloride, cobalt sulfate, nickel chloride and copper acetate in a molar ratio of 400:100:0.1:0.1:0.1:0.1:0.1:0.1, and put them into a Retsch Leyci high-throughput tissue mill MM400 rotary ball mill. Select a ball mill tank with an inner diameter of 1.8 cm and a capacity of 5 ml, and stainless steel balls with a diameter of 0.8 cm (the mass ratio of sample to ball is 2:1). Start the ball mill, set the ball milling time to 180 minutes, and the frequency to 30 Hz, until the solid reactants become a paste-like slurry A;

[0051] Step 2, separate the paste-like slurry A from the stainless steel balls, and transfer the paste-like slurry A into a centrifuge tube. Put it into a centrifuge to remove excess 1h-123-triazole. Set the centrifuge to 6000 r / min for 3 min, and obtain product B;

[0052] Step 3, put product B into a 60℃ oven for 18h drying, and grind it with a mortar to obtain product C.

[0053] Step 4, place product C in a porcelain boat under N2 atmosphere protection, and place it in a program-controlled tube furnace. Heat it to 900℃ at a heating rate of 8℃ / min, and keep it for 2 hours. Then naturally cool it to room temperature to obtain black powder D.

[0054] Step 5, assemble the photothermal water evaporator with the photothermal material and different types of polymer / cellulose substrate, etc. in a certain amount, for seawater desalination of actual water bodies.

[0055] Example 4

[0056] The preparation method of the six-element high-entropy single-atom nitrogen-rich porous photothermal material of the application is as follows:

[0057] Step 1, 1h-123-triazole, zinc chloride, chromium chloride, manganese chloride, iron chloride, cobalt chloride, nickel chloride and copper chloride are mixed uniformly at a molar ratio of 400:100:0.1:0.1:0.1:0.1:0.1:0.1 and placed in a Retsch Lei Chi high-throughput tissue instrument MM400 rotary ball mill, a ball mill tank with an inner diameter of 1.8 cm and a volume of 5 ml and stainless steel balls with a diameter of 0.8 cm (sample to ball mass ratio of 2:1) are selected, the ball milling is started, the ball milling time is set to 210 minutes, the frequency is 30 Hz, and the solid reactants are changed into paste slurry A until the solid reactants are changed into paste slurry A;

[0058] Step 2, the paste slurry A is separated from the stainless steel balls, and the paste slurry A is transferred into a centrifuge tube and centrifuged (to remove excess 1h-123-triazole) in a centrifuge at 6000 r / min for 2 min to obtain product B;

[0059] Step 3, product B is placed in an oven at 80℃ for 12h drying, and is crushed with a mortar to obtain product C.

[0060] Step 4, product C is placed in a porcelain boat and heated to 1000℃ at a heating rate of 10℃ / min in a program-controlled tube furnace under N2 atmosphere protection, and then naturally cooled to room temperature to obtain black powder D.

[0061] Step 5, the photothermal material is assembled with different types of polymer / cellulose and other substrates at a certain amount to form a photothermal water evaporator for seawater desalination of actual water bodies.

[0062] Example 5

[0063] The preparation method of the six-membered high-entropy single-atom nitrogen-rich porous photothermal material according to the application includes the following specific operation steps:

[0064] Step 1, 1h-123-triazole, zinc chloride, chromium sulfate, manganese sulfate, iron sulfate, cobalt sulfate, nickel sulfate and copper sulfate are mixed uniformly at a molar ratio of 400:100:0.1:0.1:0.1:0.1:0.1:0.1 and placed in a Retsch Lei Chi high-throughput tissue instrument MM400 rotary ball mill, a ball mill tank with an inner diameter of 1.8 cm and a volume of 5 ml and stainless steel balls with a diameter of 0.8 cm (sample to ball mass ratio of 2:1) are selected, the ball milling is started, the ball milling time is set to 180 minutes, the frequency is 30 Hz, and the solid reactants are changed into paste slurry A until the solid reactants are changed into paste slurry A;

[0065] Step 2, separate the paste slurry A from the stainless steel balls, and transfer the paste slurry A into a centrifuge tube, and place it in a centrifuge for centrifugation (remove excess 1h-123-triazole), the centrifuge is set to 6000r / min, time 3min, to obtain product B;

[0066] Step 3, place product B into an oven at 80℃ for 12h drying, and grind it with a mortar to obtain product C;

[0067] Step 4, place product C into a porcelain boat, and place it in a program-controlled tube furnace under the protection of N2 atmosphere, heat to 1000℃ at a heating rate of 5℃ / min, keep for 2h, and then naturally cool to room temperature, to obtain black powder D;

[0068] Step 5, assemble the photothermal material with different types of polymer / cellulose and other substrates into a photothermal water evaporator according to a certain amount of addition, for actual water body desalination.

[0069] As shown in Figure 2 , it is the XRD diffraction pattern of the six-element high-entropy single-atom nitrogen-rich photothermal material precursor prepared in the application, according to the curve consistent with the standard polytriazole framework, it proves the successful synthesis of the six-element high-entropy single-atom nitrogen-rich photothermal porous material precursor.

[0070] As shown in Figure 3 , it is the SEM image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material of the application. As can be seen from the figure, the photothermal material has a rich pore structure.

[0071] As shown in Figure 4 , it is the surface infrared image of the six-element high-entropy single-atom nitrogen-rich porous photothermal material of the application under the irradiation of a xenon lamp for 1h and the light intensity of 1 sun intensity. When the light irradiation is 60s, the sample surface temperature rises to 60℃, and the temperature rising rate is the fastest. During 120s-420s, the temperature rising rate slows down, and at 420s, it reaches the highest temperature of 90℃. After the xenon lamp is turned off, the temperature drops rapidly in 15s, reaching 70℃. In the following time, the sample slowly cools down, and reaches room temperature at 975s.

[0072] As shown in Figure 5 , it is the temperature rising curve of the six-element high-entropy single-atom nitrogen-rich photothermal material of the application under the irradiation of a xenon lamp for 1h and the light intensity of 1 sun intensity. When the light irradiation starts, the temperature rises rapidly from 27℃ to 60℃ in 0-60s. During 60s-240s, the temperature rising rate slightly decreases, from 60℃ to 80℃. After 240s, the temperature rises very slowly, and at 520s, the temperature of the target sample reaches 90℃. In the following time, the temperature tends to be stable.

[0073] As shown in Figure 6As shown in the figure, it is the absorption graph of the six-element high-entropy single-atom nitrogen-rich photothermal material in the ultraviolet visible light near-infrared region, and the absorption rate of the material in the range of 250-1000nm reaches more than 95%, which shows that the sample has strong absorption to ultraviolet light and visible light. The absorption rate in the near-infrared range of 1000-2500nm decreases, but it still reaches 92%, which shows that the material as a whole has high light absorption rate.

[0074] As shown in the figure, it is the absorption graph of the six-element high-entropy single-atom nitrogen-rich photothermal material in the ultraviolet visible light near-infrared region, and the absorption rate of the material in the range of 250-1000nm reaches more than 95%, which shows that the sample has strong absorption to ultraviolet light and visible light. The absorption rate in the near-infrared range of 1000-2500nm decreases, but it still reaches 92%, which shows that the material as a whole has high light absorption rate. Figure 7

[0075] The synthesis principle of the key step in the application is as follows:

[0076] (I) A simple method is used to obtain a six-element high-entropy single-atom nitrogen-rich photothermal material precursor, and a small amount of metal atoms is dispersed more uniformly in the mechanical ball milling process of MOFs, so that agglomeration does not occur, and the rich pore channels in the porous structure improve the porosity of the final product and regulate the pore structure, providing a rich path for the absorption of sunlight.

[0077] (II) A simple and controllable mechanical ball milling method is used, and 1h-123-triazole is introduced as a raw material, and the ball milling time is controlled. In the ball milling process, the mechanical activation promotes the uniform distribution of metal atoms in the MOFs material, so that agglomeration does not occur.​

Claims

1. A method for preparing a six-membered high-entropy single-atom nitrogen-rich porous photothermal material, characterized in that, The specific operation steps are as follows: Step 1, mix 1H-1, 2, 3-triazole, zinc chloride, basic chromium sulfate, manganese sulfate, ferric chloride, cobalt acetate, nickel chloride and copper acetate powder in a certain molar ratio, and then perform ball milling, the ball milling time is set to 150-210 min, and the frequency is set to 30 Hz, until the solid reactants become paste-like slurry A; The molar ratio of the 1H-1, 2, 3-triazole, zinc chloride, basic chromium sulfate, manganese sulfate, ferric chloride, cobalt acetate, nickel chloride and copper acetate is 400:100:0.1:0.1:0.1:0.1:0.1:0.1; Step 2, transfer the paste-like slurry A into a centrifuge tube, and place it in a centrifuge for centrifugation to obtain product B; the centrifugal speed is set to 6000 r / min, and the time is 2-3 min; Step 3, place product B in an oven for drying, and grind it with a mortar to obtain product C; the oven temperature is 60-80°C, and the drying time is 12-24 h; Step 4, place product C in a porcelain boat, and place it in a program-controlled tube furnace for heating under N2 atmosphere protection, and then naturally cool to room temperature to obtain a nitrogen-rich porous photothermal material; The heating rate of the program-controlled tube furnace in step 4 is 5-10°C / min, heated to 900-1000°C, and kept for 2 hours.

2. The preparation method of the hexa-element high-entropy single-atom nitrogen-rich porous photothermal material according to claim 1, characterized in that, The mass ratio of sample to grinding ball in step 1 is 2:1.

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