Method for preparing WO3.H2O / Ti3C2Tx composite material through in-situ growth

Abstract

The invention discloses a method for preparing a WO3.H2O / Ti3C2Tx composite material through in-situ growth, and belongs to the technical field of composite material preparation. The preparation method comprises the following steps: adding Ti3C2Tx powder into pure water, and uniformly dispersing to obtain a Ti3C2Tx dispersion liquid; the preparation method comprises the following steps: heating a Ti3C2Tx dispersion liquid, and adding Na2WO4. 2H2O, hydrochloric acid and oxalic acid into the Ti3C2Tx dispersion liquid while magnetically stirring to form a precipitate mixed liquid; and the precipitation mixed solution is cleaned, centrifuged and dried, and the target WO3.H2O / Ti3C2Tx composite material is obtained. According to the method, oxidation of the Ti3C2Tx is reduced while the interlayer spacing of the Ti3C2Tx is increased, a growth space is provided for WO3.H2O nanosheets, and a layered bridging structure with a high specific surface area is formed. According to the WO3.H2O / Ti3C2Tx composite material, the accordion-shaped structure of Ti3C2Tx is effectively utilized, the specific surface area of the material is increased to the maximum extent, more active adsorption sites and transmission channels are provided, and the application efficiency of the WO3.H2O / Ti3C2Tx composite material is higher. The preparation method is low in operation difficulty, simple and easy in steps, high in preparation efficiency and extremely high in popularization and application value.

Description

Technical Field

[0001] The invention belongs to the technical field of composite material preparation, and specifically relates to a method for preparing WO3·H2O / Ti3C2T by in-situ growth. x Composite material methods. Background Art

[0002] Ti3C2T x The material has a unique surface structure, graphene-like morphology, high hydrophilicity, and metal-like conductivity. x Acid corrosion, alkali corrosion and other methods can be used to destroy the weaker Ti-Al bond in the ternary layered compound Ti3AlC2 to remove the Al layer and obtain Ti3C2 two-dimensional structural materials. x It is a variety of organic functional groups modified on the surface during the etching process, which may be -H, -O, -OH, -F, etc. Ti3C2T x The material has an accordion-like structure, and further ultrasonic dispersion can obtain a single layer of Ti3C2T x . Metal oxides and Ti3C2T x The organic combination of materials will produce a composite material with better performance.

[0003] Patent CN112456551B discloses a hydrothermal method for preparing Ti3C2T x / TiO2 composite material method, but this method makes Ti3C2T x The titanium alloy is completely oxidized, and its characteristic accordion-like structure is completely destroyed, and its characteristic structure is not reasonably utilized. Patent CN112255278B discloses an ultrasonic composite method for preparing Ti3C2T x / WO3 composite material, the material has excellent ammonia sensing performance. x / WO3 composite materials, WO3 particles are aggregated on Ti3C2T x Surface. From the morphological point of view, the composite effect of the two is not good.

[0004] At present, how to do it without destroying Ti3C2T x Under the premise of the accordion-like structure of the material, the surface and interlayer space are fully utilized to make the metal oxide and Ti3C2T x The ability to organically composite is an urgent problem to be solved by the technical solution of the present invention. x Ti3C2T in composite material preparation technology x The material is easy to oxidize, the accordion-like structure is underutilized, the preparation method is cumbersome and time-consuming, and the prepared composite material has uneven morphology. The present invention aims to provide an in-situ growth method for preparing WO3·H2O / Ti3C2Tx A new approach to composite materials. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing WO3·H2O / Ti3C2T by in-situ growth. x Composite material methods.

[0006] The object of the present invention is achieved by: the in-situ growth preparation of WO3·H2O / Ti3C2T x The method of the composite material comprises the following steps: Ti3C2T x The powder was added into pure water and dispersed evenly to obtain Ti3C2T x Dispersion liquid; Ti3C2T x The dispersion is heated and stirred while adding Ti3C2T x Na2WO4·2H2O, hydrochloric acid and oxalic acid are added to the dispersion to form a precipitation mixture; The precipitated mixed solution was washed and dried to obtain the target WO3·H2O / Ti3C2T x Composite materials.

[0007] Compared with the prior art, the technical solution of the present invention has the following technical progress and beneficial effects: The technical solution prepares WO3·H2O / Ti3C2T by in-situ growth. x Composite materials, reaction temperature is less than 120℃, in increasing Ti3C2T x While increasing the interlayer spacing, it reduces its oxidation and provides growth space for WO3·H2O nanosheets, forming a layered bridging structure with high specific surface area, multiple adsorption sites and multiple channels.

[0008] The technical solution avoids Ti3C2T x While oxidizing, effectively utilize Ti3C2T x The accordion-like structure maximizes the specific surface area of ​​the material, provides more active adsorption sites and transmission channels, and makes WO3·H2O / Ti3C2T x Composite materials are more efficient in application.

[0009] The technical solution has low operating difficulty, simple and easy-to-use steps, high preparation efficiency, and the obtained target composite material has uniform morphology, which is conducive to its subsequent application. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 Ti3C2T prepared by HF acid etching x SEM image of powder; Figure 2WO3·H2O / Ti3C2T prepared by in-situ growth in Example 1 x SEM images of the composite materials. DETAILED DESCRIPTION

[0011] The present invention is further described below, but the present invention is not limited in any way. Any changes or substitutions made based on the teachings of the present invention belong to the protection scope of the present invention.

[0012] The in-situ growth method of the present invention is to prepare WO3·H2O / Ti3C2T x The method of the composite material comprises the following steps: Ti3C2T x The powder was added into pure water and dispersed evenly to obtain Ti3C2T x Dispersion liquid; Ti3C2T x The dispersion is heated and stirred while adding Ti3C2T x Na2WO4·2H2O, hydrochloric acid and oxalic acid are added to the dispersion to form a precipitation mixture; The precipitated mixed solution was washed and dried to obtain the target WO3·H2O / Ti3C2T x Composite materials.

[0013] The Ti3C2T x The powder was prepared by HF acid etching.

[0014] The etching preparation is to add 0.5g~2g Ti3AlC2 powder into a polytetrafluoroethylene beaker containing 10~40mL HF solution, stir while adding, then perform ultrasonic dispersion for 5~10min, and finally keep stirring for 18~36h. After the reaction is completed, the reactant is washed with deionized water and ethanol for many times until the pH value of the supernatant is close to the neutral value, and then centrifuged at 8000rpm to obtain a precipitate, which is dried at 60℃ to obtain Ti3C2T x Powder. (ACS nano, 2012, 6(2): 1322-1331.) The dispersion is ultrasonic dispersion with a power of 180 W and a time of 20 to 40 min, preferably 30 min.

[0015] The Ti3C2T x The mass concentration of the dispersion is 1.6-16 mg / mL, preferably 9.6 mg / mL.

[0016] The heating temperature is 60-120°C, preferably 90°C.

[0017] The stirring is magnetic stirring, and the speed is 400-800 rpm, preferably 600 rpm.

[0018] The oxalic acid: Na2WO4·2H2O powder: Ti3C2T x The mass ratio of the powders is (1-5):1:(0.5-5), preferably 3:1:3. The oxalic acid and Na2WO4·2H2O are both powders.

[0019] The volume ratio of the hydrochloric acid to pure water is (1-3):1, preferably 1:1. The hydrochloric acid is a hydrochloric acid solution with a mass fraction of 37%.

[0020] The order of adding the above reagents is: x After the dispersion is heated to a predetermined temperature, Na2WO4·2H2O powder is added in sequence while being kept warm and stirred, followed by hydrochloric acid dropwise, and finally oxalic acid powder, with stirring during the additions, for 2 to 4 hours, preferably 3 hours.

[0021] The solvent used for the washing is pure water, and the washing times are 3 to 8 times, preferably 5 times. After washing, centrifugation is performed at a speed of 40,000 to 80,000 rpm, preferably 60,000 rpm.

[0022] The drying temperature is 40-80° C., preferably 60° C., and the drying time is 6-12 hours, preferably 8 hours.

[0023] Example 1 A method for preparing WO3·H2O / Ti3C2T by in-situ growth x The method of the composite material comprises the following steps: 480mgTi3C2T x The powder was added to 50 mL of pure water and ultrasonically dispersed at 180 W for 30 min. Then it was transferred to a magnetic stirrer and stirred at 600 rpm while heating. At the same time, the dispersion was heated to 90 °C to obtain a uniform Ti3C2T x Dispersion.

[0024] Maintaining 90°C, in Ti3C2T x While the dispersion was being stirred and heated, 160 mg of Na2WO4·2H2O powder was added in sequence, followed by 50 mL of 37% hydrochloric acid solution, and finally 480 mg of oxalic acid powder. The mixture was stirred for 3 h to form a precipitated mixed solution.

[0025] The precipitated mixed solution was washed with pure water for 5 times, then centrifuged at a speed of 60000rpm and dried in a blast drying oven at 60℃ for 8h to obtain the target WO3·H2O / Ti3C2T x Composite materials.

[0026] Example 2 A method for preparing WO3·H2O / Ti3C2T by in-situ growth x The method of the composite material comprises the following steps: 800mgTi3C2T x The powder was added to 50 mL of pure water and ultrasonically dispersed at 180 W for 40 min. Then it was transferred to a magnetic stirrer and stirred at 400 rpm while heating. The dispersion was heated to 60 °C to obtain a uniform Ti3C2T x Dispersion.

[0027] Maintaining 60°C, Ti3C2T x While the dispersion was being stirred and heated, 160 mg of Na2WO4·2H2O powder was added in sequence, 150 mL of 37% hydrochloric acid solution was added dropwise, and finally 800 mg of oxalic acid powder was added and stirred for 4 h to form a precipitated mixed solution.

[0028] The precipitated mixed solution was washed with pure water for three times, then centrifuged at a speed of 60000 rpm and dried in a blast drying oven at 40°C for 12 h to obtain the target WO3·H2O / Ti3C2T x Composite materials.

[0029] Example 3 A method for preparing WO3·H2O / Ti3C2T by in-situ growth x The method of the composite material comprises the following steps: 80mgTi3C2T x The powder was added to 50 mL of pure water and ultrasonically dispersed at 180 W for 20 min. The powder was then transferred to a magnetic stirrer and stirred at 800 rpm while heating. The dispersion was heated to 120 °C to obtain a uniform Ti3C2T x Dispersion.

[0030] Maintaining 120℃, in Ti3C2T x While the dispersion was being stirred and heated, 160 mg of Na2WO4·2H2O powder was added in sequence, followed by 50 mL of 37% hydrochloric acid solution, and finally 320 mg of oxalic acid powder. The mixture was stirred for 2 h to form a precipitated mixed solution.

[0031] The precipitated mixed solution was washed with pure water for 8 times, then centrifuged at a speed of 60000rpm and dried in a forced air drying oven at 80℃ for 6h to obtain the target WO3·H2O / Ti3C2T x Composite materials.

[0032] Example 4 ——Comparative ratio Ti3C2T xThe powder was added into pure water without ultrasonic dispersion, and the rest of the steps were the same as those in Example 1.

[0033] Since ultrasonic dispersion was not performed and the mechanical stirring speed was low, the WO3·H2O / Ti3C2T prepared by in-situ growth method x The WO3·H2O nanosheets in the composite material are not x The interlayer growth is concentrated in Ti3C2T x Surface, even agglomeration occurs.

[0034] Example 5 ——Comparative ratio Ti3C2T x The dispersion was heated to 180°C and maintained at this temperature. x During the stirring and heating of the dispersion, Na2WO4·2H2O powder was added in sequence, hydrochloric acid solution was added dropwise, and oxalic acid powder was added lastly. The remaining steps were the same as those in Example 1.

[0035] Prepared WO3·H2O / Ti3C2T x In composite materials, Ti3C2T x In addition to WO3·H2O nanosheets, there are also small particles on the surface, Ti3C2T x Oxidation occurred, which was not conducive to the in-situ growth of WO3·H2O nanosheets.

[0036] In contrast, the WO3·H2O / Ti3C2T prepared by in-situ growth in Example 1 x Composite material, WO3·H2O nanosheets are evenly distributed on Ti3C2T x Surface and interlayer, Ti3C2T x The layers are clearly defined, forming a multi-layer sandwich three-dimensional structure, which effectively increases the specific surface area of ​​the material and provides more adsorption sites.

Claims

1. In-situ growth preparation of WO3·H2O / Ti3C2T x A method of making a composite material, characterized in that Including the following processes: Ti3C2T x The powder was added into pure water and dispersed evenly to obtain Ti3C2T x Dispersion liquid; Ti3C2T x The dispersion is heated and stirred while adding Ti3C2T x Na2WO4·2H2O, hydrochloric acid and oxalic acid are added to the dispersion to form a precipitation mixture; The precipitated mixed solution was washed and dried to obtain the target WO3·H2O / Ti3C2T x Composite materials.

2. The preparation method according to claim 1, characterized in that The Ti3C2T x The powder was prepared by HF acid etching.

3. The preparation method according to claim 1, characterized in that The dispersion is ultrasonic dispersion with a power of 180 W and a time of 20 to 40 min.

4. The preparation method according to claim 1, characterized in that The Ti3C2T x The mass concentration of the dispersion is 1.6~16mg / mL.

5. The preparation method according to claim 1, characterized in that The heating temperature is 60-120°C.

6. The preparation method according to claim 1, characterized in that The stirring is magnetic stirring at a speed of 400-800 rpm.

7. The preparation method according to claim 1, characterized in that The oxalic acid:Na2WO4·2H2O:Ti3C2T x The mass ratio of the powder is (1~5):1:(0.5~5).

8. The preparation method according to claim 1, characterized in that The volume ratio of hydrochloric acid to pure water is (1-3):

1.

9. The preparation method according to claim 1, characterized in that The solvent used for the cleaning is pure water, and the number of cleaning times is 3 to 8 times.

10. The preparation method according to claim 1, characterized in that The drying temperature is 40-80° C. and the drying time is 6-12 hours.

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