A magnéli phase v6o 11 Piezocatalyst, method for preparing and use thereof

Abstract

The application provides a Magnéli phase V6O 11 The application provides a piezoelectric catalyst, a preparation method and application thereof, the preparation method comprising the following steps: step 1: dissolving NH4VO3 in a citric acid solution, uniformly stirring to form a precursor solution A; carrying out a hydrothermal reaction on the precursor solution A, separating and washing and drying the obtained product to obtain a powder NH4(V3O8); step 2: dissolving VO2 powder and NH4(V3O8) powder in a mixed solution of isopropyl alcohol and H2O, uniformly stirring to form a precursor solution B, carrying out a hydrothermal reaction on the precursor solution B, separating and washing and drying the obtained product to obtain a Magnéli phase V6O 11 The application provides a piezoelectric catalyst, a preparation method and application thereof, the preparation method comprising the following steps: step 1: dissolving NH4VO3 in a citric acid solution, uniformly stirring to form a precursor solution A; carrying out a hydrothermal reaction on the precursor solution A, separating and washing and drying the obtained product to obtain a powder NH4(V3O8); step 2: dissolving VO2 powder and NH4(V3O8) powder in a mixed solution of isopropyl alcohol and H2O, uniformly stirring to form a precursor solution B, carrying out a hydrothermal reaction on the precursor solution B, separating and washing and drying the obtained product to obtain a Magnéli phase V6O 11 The application provides a piezoelectric catalyst, a preparation method and application thereof, the preparation method comprising the following steps: step 1: dissolving NH4VO3 in a citric acid solution, uniformly stirring to form a precursor solution A; carrying out a hydrothermal reaction on the precursor solution A, separating and washing and drying the obtained product to obtain a powder NH4(V3O8); step 2: dissolving VO2 powder and NH4(V3O8) powder in a mixed solution of isopropyl alcohol and H2O, uniformly stirring to form a precursor solution B, carrying out a hydrothermal reaction on the precursor solution B, separating and washing and drying the obtained product to obtain a Magnéli phase V6O

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energy storage piezoelectric dark catalysis and photo-thermal energy storage piezoelectric catalytic materials and preparation, in particular to a Magnéli phase V6O 11 Piezoelectric catalyst and preparation method and application thereof. BACKGROUND

[0002] V6O 11 is a kind of transition metal compound with particularity due to its ability to form variable valence compounds, and its general formula is V n O 2n-1 (n = 3, 6, 9), also known as Magnéli phase series. The crystal structure of the members of this series represents a hexagonal packing of oxygen ions. V6O 11 The crystal structure is triclinic with P-1 (2) space group. Part of the octahedral voids in the structure are filled with V 3+ and V 4+ ions, forming VO2 rutile blocks, which are limited by so-called crystal shear planes and form associations with V2O3. Non-stoichiometric V6O 11 will undergo a metal-insulator transition, accompanied by several orders of magnitude of conductivity transition.

[0003] V6O 11 The number of V 3+ and V 4+ in the crystal is 1:2, that is, the number of V 3+ is half of V 4+ . According to their ionic radii, during the metal-insulator transition, all V 3+ and half of V 4+ ions are simultaneously located at odd and even sites. The other half of V 4+ ions will be evenly distributed on the remaining odd and even chains. The mutual arrangement of homovalent chains and the filling of the chains themselves make V6O 11 have a certain randomness, which can adjust the exchange of residual electrons between individual vanadium ions, so that V6O 11 divides the jump conduction, and after that, there are a relatively large number of residual free carriers, which can be virtually exchanged between V 3+ and V 4+ ions that are not completely ordered. And V6O 11 exists a strong transition, which involves strong electron correlation, so there is a small polaron transition phenomenon in V6O 11 , which can further absorb near-infrared light.

[0004] US4372653A discloses a modulator consisting of transition metal oxides (VO, VO2, V2O3, V3O5, V4O7, V5O9, V6O 11 etc.) that converts unpolarized optical energy of an incident beam into a train of alternating polarized and unpolarized segments. The incident unpolarized optical energy beam is incident on the outer surface of the modulating device at the Brewster angle. The preparation process of V6O 11 is not mentioned. CN107010668B discloses a device and method for preparing ultrafine Magnéli phase V n O 2n-1 powder by high-temperature gas phase reduction deposition, wherein V2O5 is used as vanadium source, and through precise temperature control, V2O5 is first sublimated and then cooled in a CO2 and H2 atmosphere at a high temperature of 1000-1200℃ to prepare ultrafine Magnéli phase V n O 2n-1 powder. The use of H2 atmosphere at high temperature increases the risk in the preparation process. Due to the difficulty in preparation, the complexity and danger of the preparation process and device, there is a certain bottleneck in the development of the photocatalytic field. SUMMARY

[0005] In view of the problems in the prior art, the present application provides a Magnéli phase V6O 11 piezoelectric catalyst, a preparation method and application thereof, which has good broad-spectrum cyclic degradation effect on organic pollutant under dark conditions and full spectrum.

[0006] The present application is realized by the following technical solutions:

[0007] The present application provides a preparation method of Magnéli phase V6O 11 piezoelectric catalyst, comprising the following steps:

[0008] Step 1: dissolve NH4VO3 in a citric acid solution, stir uniformly to form precursor solution A, and perform hydrothermal reaction on the precursor solution A, separate the obtained product and wash and dry to obtain powder NH4(V3O8);

[0009] Step 2: dissolve VO2 powder and NH4(V3O8) powder in a mixed solution of isopropyl alcohol and H2O, stir uniformly to form precursor solution B, perform hydrothermal reaction on the precursor solution B, separate the obtained product and wash and dry to obtain Magnéli phase V6O 11 piezoelectric catalyst.

[0010] Preferably, in step 1, the ratio of NH4VO3 to citric acid solution is (11.00-11.15) mmol:(20-30) mL, and the concentration of the citric acid solution is 0.50-0.55 mol / L.

[0011] Preferably, in step 1, the hydrothermal reaction temperature is 100-120℃, and the time is 10-14 h.

[0012] Preferably, in step 2, the VO2 powder is prepared by dissolving vanadium oxyacetone in a mixed solution of isopropyl alcohol and water, stirring to form a precursor solution, and then performing a hydrothermal reaction on the precursor solution, separating and washing the precipitate, and drying to obtain the VO2 powder.

[0013] Preferably, in step 2, the mass ratio of the VO2 powder to the NH4(V3O8) powder is (2.5-3.5):1.

[0014] Preferably, in step 2, the hydrothermal reaction temperature is 180-200℃, and the time is 0.5-3.0 h.

[0015] Preferably, in step 2, the volume ratio of isopropyl alcohol to H2O is (11.5-13.5):(11.5-13.5).

[0016] The application provides a Magnéli phase V6O 11 piezocatalyst.

[0017] The application provides the Magnéli phase V6O 11 application of the piezocatalyst in degradation of organic pollutants under dark conditions or light conditions.

[0018] Preferably, the organic pollutants are antibiotics or organic substances, the antibiotics are tetracycline or ciprofloxacin, and the organic substances are bisphenol A, salicylic acid, coumarin or phenol.

[0019] Compared with the prior art, the application has the following beneficial effects:

[0020] The application uses VO2 and NH4(V3O8) as raw materials, isopropyl alcohol and H2O as solvents, and a hydrothermal method to prepare a silk sponge structure V6O 11 nanosheet at a low temperature, and the preparation method is simple, easy to operate and safe.

[0021] The V6O 11 prepared by the application is a piezocatalyst for energy storage and piezocatalysis under dark conditions or light-heat piezocatalysis, and the V6O 11 has a large number of free electrons and a large number of holes generated by the variable valence of V metal in the material, and is disturbed by mechanical stress to form a strain, and the V6O 11The internal piezoelectric potential is generated, and then a piezoelectric field is formed. V6O 11 The polarized electric field exists in the crystal, has piezoelectric properties, and can store electrons and holes. In the dark, the Magnéli phase V6O 11 The strain formed by the mechanical stress disturbance orients and enhances the internal polarized electric field, and rapidly releases the stored electrons and holes in the dark to carry out catalytic reactions. Meanwhile, the strain formed by the mechanical stress disturbance orients and enhances the internal polarized electric field, and rapidly releases the stored electrons and holes in the dark to carry out catalytic reactions. Meanwhile, the strain formed by the mechanical stress disturbance orients and enhances the internal polarized electric field, and rapidly releases the stored electrons and holes in the dark to carry out catalytic reactions. 11 The piezoelectric catalyst generates piezoelectric charges, and the released stored electrons and piezoelectric charges degrade organic pollutants. The piezoelectric energy storage effect greatly improves the dark catalytic ability of the material to a level comparable to the photocatalytic ability, so that the material has excellent photocatalytic ability and high-efficiency dark catalytic ability, realizes dark-full-spectrum piezoelectric catalytic ability, has good degradation ability for organic pollutants, and has good dark cycling stability. In addition, V6O 11 Small polaron transition also exists in V6O 11 The photo-thermal energy storage piezoelectric catalyst has good application prospects in water pollution purification in the full-spectrum and dark. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0023] Figure 1 is an SEM image of the catalyst prepared in Example 1.

[0024] Figure 2 is an STEM image of the catalyst prepared in Example 1.

[0025] Figure 3 is an HRTEM image of the catalyst prepared in Example 1.

[0026] Figure 4 is a phase change diagram of Example 2 of the present application.

[0027] Figure 5 is a phase change diagram of Example 3 of the present application.

[0028] Figure 6 is a phase change diagram of Example 1 of the present application.

[0029] Figure 7is the amplitude change graph of Example 2 of the present application.

[0030] Figure 8 is the amplitude change graph of Example 3 of the present application.

[0031] Figure 9 is the amplitude change graph of Example 1 of the present application.

[0032] Figure 10 is the degradation curve of 40 mg / L tetracycline by the catalyst prepared in Comparative Example 1 and Examples 1, 2, 3 of the present application under visible light.

[0033] Figure 11 is the apparent rate constant of 40 mg / L tetracycline by the catalyst prepared in Comparative Example 1 and Examples 1, 2, 3 of the present application under visible light.

[0034] Figure 12 is the TOC removal graph of 40 mg / L tetracycline by the catalyst prepared in Example 1 of the present application under visible light.

[0035] Figure 13 is the cyclic degradation graph of 40 mg / L tetracycline by the catalyst prepared in Example 1 of the present application under visible light.

[0036] Figure 14 is the active species capture graph of the catalyst prepared in Example 1 of the present application under visible light.

[0037] Figure 15 is the degradation curve of 40 mg / L tetracycline by the catalyst prepared in Comparative Example 1 and Examples 1, 2, 3 of the present application under near-infrared light.

[0038] Figure 16 is the apparent rate constant of 40 mg / L tetracycline by the catalyst prepared in Comparative Example 1 and Examples 1, 2, 3 of the present application under near-infrared light.

[0039] Figure 17 is the TOC removal graph of 40 mg / L tetracycline by the catalyst prepared in Example 1 of the present application under near-infrared light.

[0040] Figure 18 is the cyclic degradation graph of 40 mg / L tetracycline by the catalyst prepared in Example 1 of the present application under near-infrared light.

[0041] Figure 19 is the active species capture graph of the catalyst prepared in Example 1 of the present application under near-infrared light.

[0042] Figure 20 is the infrared temperature imaging graph of 40 mg / L tetracycline degraded by the catalyst prepared in Example 1 of the present application under visible light for 90 min.

[0043] Figure 21 is the infrared temperature imaging diagram of the catalyst prepared in Example 1 of the present application for degrading 40 mg / L tetracycline under near-infrared light for 90 min.

[0044] Figure 22 is the degradation curve diagram of the catalyst prepared in Example 1 of the present application for 40 mg / L tetracycline under monochromatic light of 740 nm, 850 nm, 940 nm and 1100 nm.

[0045] Figure 23 is the degradation rate diagram of the catalyst prepared in Example 1 of the present application for 20 mg / L phenol, 20 mg / L ciprofloxacin, 20 mg / L salicylic acid, 20 mg / L bisphenol A and 20 mg / L coumarin under visible light.

[0046] Figure 24 is the degradation rate diagram of the catalyst prepared in Example 1 of the present application for 20 mg / L phenol, 20 mg / L ciprofloxacin, 20 mg / L salicylic acid, 20 mg / L bisphenol A and 20 mg / L coumarin under near-infrared light.

[0047] Figure 25 is the TOC removal rate diagram of the catalyst prepared in Example 1 of the present application for 20 mg / L phenol, 20 mg / L ciprofloxacin, 20 mg / L salicylic acid, 20 mg / L bisphenol A and 20 mg / L coumarin under visible light.

[0048] Figure 26 is the TOC removal rate diagram of the catalyst prepared in Example 1 of the present application for 20 mg / L phenol, 20 mg / L ciprofloxacin, 20 mg / L salicylic acid, 20 mg / L bisphenol A and 20 mg / L coumarin under near-infrared light.

[0049] Figure 27 is the removal curve of the catalyst prepared in Comparative Example 1 and Examples 1, 2 and 3 of the present application for 40 mg / L tetracycline in the dark.

[0050] Figure 28 is the apparent rate constant of the catalyst prepared in Comparative Example 1 and Examples 1, 2 and 3 of the present application for 40 mg / L tetracycline in the dark.

[0051] Figure 29 is the cyclic degradation diagram of the catalyst prepared in Example 1 of the present application for 40 mg / L tetracycline in the dark after 16 times of dark cycling, followed by 30 min of light irradiation.

[0052] Figure 30Figure 6 is a plot of TOC removal rate of the catalyst prepared in Example 1 of the present application in the dark after 16 cycles of 40 mg / L tetracycline, followed by 30 min of light and then continued in the dark.

[0053] Figure 31 Figure 7 is a plot of absorbance of 70 mg / L methylene blue in the dark for the catalyst prepared in Example 1 of the present application.

[0054] Figure 32 Figure 8 is a plot of active species capture in the dark for the catalyst prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0055] Other advantages and novel features of the present application will become apparent to those skilled in the art from the following detailed description, which, when taken in conjunction with the drawings, discloses various embodiments of the present application. While the description below contains many specifics, these are presented in a way that is meant to be illustrative and not limiting of the various embodiments of the present application. It is intended that the scope of the present application covered by the appended claims and their equivalents.

[0056] It should be noted that the technical equipment or devices not specifically mentioned in the following examples are all conventional technical equipment or devices in the art.

[0057] It should be noted that the terms "comprises" and "comprising" and any variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, system, product or apparatus that comprises a list of steps or units does not necessarily comprise only those steps or units but can include other steps or units not expressly listed or inherent to such process, method, product or apparatus. Further, unless expressly stated to the contrary, the description of a process, method, product, or apparatus equally applies to an individual step of the process, method, product or apparatus, and vice versa. Changes or modifications to the relative arrangement of individual steps or units, or to the relative arrangement of the features of the present application, do not depart from the scope of the present application, provided that no technical content is materially changed.

[0058] The Magnéli phase V6O 11 The method for preparing the piezocatalyst comprises the following steps:

[0059] Step 1: A certain amount of NH4VO3 is dissolved in a citric acid solution of a certain concentration, and stirred to form precursor solution A. The precursor solution A is moved into a polytetrafluoroethylene-lined autoclave for hydrothermal treatment for a period of time. After cooling to room temperature, centrifugal cleaning is performed, and the centrifuged powder is washed several times with anhydrous ethanol and deionized water, centrifuged and vacuum dried overnight to obtain the powder NH4(V3O8).

[0060] Step 2: VO2 and powder NH4(V3O8) are dissolved in a mixed solution of isopropyl alcohol and H2O at a certain mass ratio, stirred uniformly to form precursor solution B, precursor solution B is moved into a polytetrafluoroethylene lined autoclave, and hydrothermal preservation is carried out for a certain time, after the solution is cooled, centrifugation is carried out to obtain a precipitate, the precipitate is washed with anhydrous ethanol and deionized water for several times, and vacuum drying is carried out overnight to obtain black green V6O 11 piezoelectric catalyst.

[0061] In step 1 of the application, the ratio of NH4VO3 to citric acid solution is (11.00-11.15) mmol:(20-30) mL, the concentration of the citric acid solution is 0.50-0.55 mol / L, stirring is carried out for 20-30 h, precursor solution A is formed, precursor solution A is moved into a polytetrafluoroethylene lined autoclave at a filling amount of 40%-60%, the precursor solution A in the polytetrafluoroethylene lined autoclave is preserved at 100-120 DEG C for 10-14 h, after cooling to room temperature, centrifugation is carried out, the powder centrifuged out is washed with anhydrous ethanol and deionized water respectively for 4 times, and the powder after washing is vacuum dried at 50-70 DEG C overnight to obtain powder NH4(V3O8).

[0062] In step 2 of the application, VO2 and NH4(V3O8) powder are dissolved in a mixed solution of 11.5 mL-13.5 mL isopropyl alcohol and 11.5 mL-13.5 mL H2O at a mass ratio of (2.5-3.5):1, stirring is carried out for 25-35 min to form a precursor solution, the precursor solution is moved into a polytetrafluoroethylene lined autoclave at a filling amount of 40%-60%, and hydrothermal preservation is carried out at 180-200 DEG C for 0.5-3.0 h, after the solution is cooled, centrifugation is carried out to obtain a precipitate, and the precipitate is washed with anhydrous ethanol and deionized water respectively, and vacuum drying is carried out at 50-70 DEG C overnight to obtain black green V6O 11 photothermal energy storage piezoelectric catalyst, the chemical general formula of which is V n O 2n-1 (n=3-9).

[0063] The Magnéli phase V6O 11 is a triclinic phase structure, space group: P-1 (2). The stored electron concentration is 498.50 μmol·g -1 , which is an energy storage catalyst; the d 33 value is 5.70 nm·V -1 , has piezoelectric properties; and has good photothermal properties, and after visible light / near infrared light irradiation for 90 min, the temperature of the reaction system is increased by 18.4 DEG C / 22.5 DEG C.

[0064] Therefore, the Magnéli phase V6O 11The photo-thermal piezoelectric catalyst has the effect of catalytic degradation of organic pollutants under full spectrum-dark conditions, and has good full spectrum-dark cycle stability. The organic pollutants are antibiotics or organic matter, the antibiotics are tetracycline or ciprofloxacin. The organic matter is bisphenol A, salicylic acid, coumarin or phenol.

[0065] V6O 11 The strain-released stored electron holes and newly generated piezoelectric charges have good degradation effect on antibiotics and organic matter. In addition, V6O 11 has excellent dark cycle stability, which improves its practical application potential.

[0066] Comparative Example 1

[0067] Step 1: 0.276 mmol of vanadyl acetylacetonate was dissolved in a mixed solution of 22.5 mL of isopropanol and 7.5 mL of water, stirred for 40 min to form precursor solution A;

[0068] Step 2: The precursor solution A was placed in a hydrothermal kettle, the filling amount of the precursor solution A in the polytetrafluoroethylene liner was 70%, and the hydrothermal reaction was carried out at 190°C for 3h, and the precipitate was obtained by centrifugation;

[0069] Step 3: The precipitate after centrifugation was washed with deionized water and anhydrous ethanol for 3 times, and then vacuum dried at 60°C for 12h to obtain VO2 powder.

[0070] Example 1

[0071] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of 0.53 mol / L citric acid solution, stirred for 24h to form precursor solution A. The precursor solution A was transferred into a polytetrafluoroethylene liner autoclave with a filling amount of 50%, and was incubated at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, the powder obtained by centrifugation was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0072] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL of isopropanol and 12.5 mL of H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, and then transferred into a polytetrafluoroethylene liner autoclave with a filling amount of 50%. Hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washing. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black-green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0073] Example 2

[0074] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. The precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and was kept at 110°C for 12 h. After cooling to room temperature, centrifugal cleaning was performed. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and was vacuum dried at 60°C overnight to obtain powder M.

[0075] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL of isopropanol and 12.5 mL of H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B. The precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and was hydrothermally kept at 190°C for 0.5 h respectively. After the solution was cooled, centrifugation was performed to obtain precipitates and clean them. The precipitates were washed with anhydrous ethanol and deionized water for 4 times, and were vacuum dried at 60°C overnight to obtain black-green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0076] Example 3

[0077] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. The precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and was kept at 110°C for 12 h. After cooling to room temperature, centrifugal cleaning was performed. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and was vacuum dried at 60°C overnight to obtain powder M.

[0078] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL of isopropanol and 12.5 mL of H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B. The precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and was hydrothermally kept at 190°C for 0.5 h respectively. After the solution was cooled, centrifugation was performed to obtain precipitates and clean them. The precipitates were washed with anhydrous ethanol and deionized water for 4 times, and were vacuum dried at 60°C overnight to obtain black-green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0079] Example 4

[0080] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. The precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and was kept at 110°C for 12 h. After cooling to room temperature, centrifugal cleaning was performed. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and was vacuum dried at 60°C overnight to obtain powder M.

[0081] Step 2: Dissolve VO2 and powder M in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stir for 30 min to form precursor solution B, move precursor solution B into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and hydrothermally incubate at 190 °C for 1.5 h, respectively. After the solution cools, centrifuge to obtain the precipitate and wash. Wash the precipitate with anhydrous ethanol and deionized water 4 times, and vacuum dry at 60 °C overnight to obtain black-green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0082] Example 5

[0083] Step 1: Dissolve 11.11 mmol of NH4VO3 in 25 mL of a citric acid solution with a concentration of 0.53 mol / L, stir for 24 h to form precursor solution A. Move precursor solution A into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and incubate at 110 °C for 12 h. After cooling to room temperature, centrifuge and wash. Centrifuged powder is washed with anhydrous ethanol and deionized water 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0084] Step 2: Dissolve VO2 and powder M in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stir for 30 min to form precursor solution B, move precursor solution B into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and hydrothermally incubate at 190 °C for 2 h, respectively. After the solution cools, centrifuge to obtain the precipitate and wash. Wash the precipitate with anhydrous ethanol and deionized water 4 times, and vacuum dry at 60 °C overnight to obtain black-green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0085] Example 6

[0086] Step 1: Dissolve 11.11 mmol of NH4VO3 in 25 mL of a citric acid solution with a concentration of 0.53 mol / L, stir for 24 h to form precursor solution A. Move precursor solution A into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and incubate at 110 °C for 12 h. After cooling to room temperature, centrifuge and wash. Centrifuged powder is washed with anhydrous ethanol and deionized water 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0087] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 190°C for 2.5 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0088] Example 7

[0089] Step 1: 11.00 mmol of NH4VO3was dissolved in 25 mL of a citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 110°C for 12 h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0090] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 190°C for 2.5 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0091] Example 8

[0092] Step 1: 11.15 mmol of NH4VO3was dissolved in 25 mL of a citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 110°C for 12 h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0093] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and hydrothermal incubation was carried out at 190°C for 3h respectively, and the precipitate was obtained by centrifugation after the solution was cooled and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0094] Example 9

[0095] Step 1: 11.11 mmol of NH4VO3 was dissolved in 20 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and incubated at 110°C for 12h, and centrifuged and washed after cooling to room temperature. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0096] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and hydrothermal incubation was carried out at 190°C for 3h respectively, and the precipitate was obtained by centrifugation after the solution was cooled and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0097] Example 10

[0098] Step 1: 11.11 mmol of NH4VO3 was dissolved in 30 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and incubated at 110°C for 12h, and centrifuged and washed after cooling to room temperature. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0099] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0100] Example 11

[0101] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.50 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0102] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0103] Example 12

[0104] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.55 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0105] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and hydrothermal incubation was carried out at 190°C for 3h respectively, and the precipitate was obtained by centrifugation after the solution was cooled and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0106] Example 13

[0107] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 20h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and incubated at 110°C for 12h, and centrifuged and washed after cooling to room temperature. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0108] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and hydrothermal incubation was carried out at 190°C for 3h respectively, and the precipitate was obtained by centrifugation after the solution was cooled and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0109] Example 14

[0110] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 30h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and incubated at 110°C for 12h, and centrifuged and washed after cooling to room temperature. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0111] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0112] Example 15

[0113] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 40% filling amount, and incubated at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0114] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0115] Example 16

[0116] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 40% filling amount, and incubated at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0117] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, centrifugation was performed to obtain the precipitate and washing. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0118] Example 17

[0119] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 100°C for 12h. After cooling to room temperature, centrifugation and washing were performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0120] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, centrifugation was performed to obtain the precipitate and washing. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0121] Example 18

[0122] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 100°C for 12h. After cooling to room temperature, centrifugation and washing were performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0123] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0124] Example 19

[0125] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110°C for 10h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0126] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0127] Example 20

[0128] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110°C for 14h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0129] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h respectively, and the precipitate was obtained after centrifugation and washing after the solution was cooled. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0130] Example 21

[0131] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110°C for 12h, and centrifuged and washed after cooling to room temperature. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 50°C overnight to obtain powder M.

[0132] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal incubation was carried out at 190°C for 3h respectively, and the precipitate was obtained after centrifugation and washing after the solution was cooled. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0133] Example 22

[0134] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110°C for 12h, and centrifuged and washed after cooling to room temperature. The centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 50°C overnight to obtain powder M.

[0135] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0136] Example 23

[0137] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0138] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 2.5:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0139] Example 24

[0140] Step 1: 11.11 mmol of NH4VO3 was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0141] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3.5:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0142] Example 25

[0143] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0144] Step 2: VO2and powder M were dissolved in a mixed solution of 11.5 mL isopropanol and 11.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 190°C for 3h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0145] Example 26

[0146] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermal treatment was carried out at 110°C for 12h. After cooling to room temperature, centrifugal washing was carried out, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60°C overnight to obtain powder M.

[0147] Step 2: VO2and powder M were dissolved in a mixed solution of 13.5 mL isopropanol and 13.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0148] Example 27

[0149] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0150] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 25 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0151] Example 28

[0152] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0153] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 35 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0154] Example 29

[0155] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0156] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 40% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0157] Example 30

[0158] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0159] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 60% filling volume, and hydrothermally incubated at 190 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0160] Example 31

[0161] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0162] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and hydrothermally incubated at 180 °C for 3 h, respectively. After the solution was cooled, the precipitate was obtained by centrifugation and washed. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0163] Example 32

[0164] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was transferred into a polytetrafluoroethylene-lined autoclave with a 50% filling volume, and incubated at 110 °C for 12 h. After cooling to room temperature, centrifugal washing was performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0165] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and was hydrothermally treated at 200 °C for 3 h, respectively. After the solution was cooled, centrifugation was performed to obtain the precipitate and washing. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0166] Example 33

[0167] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and was hydrothermally treated at 110 °C for 12 h. After cooling to room temperature, centrifugation and washing were performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0168] Step 2: VO2and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and was hydrothermally treated at 190 °C for 3 h, respectively. After the solution was cooled, centrifugation was performed to obtain the precipitate and washing. The precipitate was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 50 °C overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0169] Example 34

[0170] Step 1: 11.11 mmol of NH4VO3was dissolved in 25 mL of citric acid solution with a concentration of 0.53 mol / L, stirred for 24 h to form precursor solution A. Precursor solution A was moved into a polytetrafluoroethylene-lined autoclave with a 50% filling amount, and was hydrothermally treated at 110 °C for 12 h. After cooling to room temperature, centrifugation and washing were performed, and the centrifuged powder was washed with anhydrous ethanol and deionized water for 4 times, and vacuum dried at 60 °C overnight to obtain powder M.

[0171] Step 2: VO2 and powder M were dissolved in a mixed solution of 12.5 mL isopropanol and 12.5 mL H2O with a mass ratio of 3:1, stirred for 30 min to form precursor solution B, precursor solution B was moved into a polytetrafluoroethylene lined autoclave with a 50% filling amount, and hydrothermal treatment was carried out at 190℃ for 3h respectively, and after the solution was cooled, centrifugation was carried out to obtain the precipitate and washing was carried out. The precipitate was washed with anhydrous ethanol and deionized water 4 times, and vacuum dried at 70℃ overnight to obtain black green V6O 11 Photo-thermal energy storage piezoelectric catalyst.

[0172] The above conclusions and mechanisms are described in detail below.

[0173] Figure 1 is the SEM image of the catalyst prepared in Example 1. V6O 11 is an irregular flaky structure stacked by flaky structures of different sizes. Figure 2 is the STEM image of the catalyst prepared in Example 1. From the V6O 11 STEM image, it can be seen that the V6O 11 nanosheet presents a loofah structure, and there are a large number of pore structures of about 2nm. Figure 3 is the HRTEM image of the catalyst prepared in Example 1. V6O 11 The lattice fringe spacing in the HRTEM image of V6O 11 is 0.331 nm, 0.306 nm and 0.257 nm, corresponding to its (-120), (-1-17) and (-205) crystal planes, further indicating that the flaky V6O 11 is formed.

[0174] Figure 4 、 Figure 5 and Figure 6 are the phase change diagrams of Example 2, Example 3 and Example 1 respectively. After applying a deflection voltage of 10V, the phase angle flips about 180°, proving that the dipole is easy to be turned by the external electric field.

[0175] Figure 7 、 Figure 8 and Figure 9 are the amplitude change diagrams of Example 2, Example 3 and Example 1 respectively. Under the action of the electric field, the samples prepared in the three examples all appear a typical "butterfly curve", and a strain-electric field hysteresis phenomenon is produced, proving that V6O 11 has obvious piezoelectric response at the nanoscale, and the d 33 values of Example 2, Example 3 and Example 1 calculated by the piezoelectric "butterfly curve" are 2.25, 2.55, 5.70 nm·V -1 , respectively, proving that V6O 11has better piezoelectric performance. Larger piezoelectric polarization characteristics can induce energy storage catalysts to store electric charges and generate piezoelectric charges under mechanical stress, improve catalytic activity in dark conditions, and thus, under the disturbance of mechanical stress strain, V6O 11 The photo-thermal energy storage piezoelectric catalyst stores and generates piezoelectric charges, and the released stored charges and newly generated piezoelectric charges perform redox reactions, so that V6O 11 has strong dark catalytic ability.

[0176] Figure 10 and Figure 11 The degradation curves and apparent rate constants of the catalysts prepared in Comparative Example 1 and Examples 2, 3, and 1 for 40 mg / L tetracycline under visible light are shown. After 90 min of direct visible light irradiation, the degradation rates of Comparative Example 1, Example 2, Example 3, and Example 1 for 40 mg / L TC were 82.00%, 71.38%, 73.28%, and 92.02%, respectively, and the apparent rate constants of each sample were 0.02376 min -1 , 0.01780 min -1 , 0.01894 min -1 , and 0.03781 min -1 , respectively. Figure 12 and Figure 13 The TOC removal rate graph and cyclic degradation graph of the catalyst prepared in Example 1 of the present application for 40 mg / L tetracycline under visible light are shown. V6O 11 The TOC removal rate for 40 mg / L TC reached 79.74% after 90 min of direct visible light irradiation, indicating that it has good mineralization ability. V6O 11 The efficiency remained at 89.09% after four cycles of degradation under direct visible light irradiation, and the degradation activity only decreased by 4.57% compared with the first degradation, indicating that it has good cyclic stability under direct visible light irradiation.

[0177] Figure 14 The active species capture graph of the catalyst prepared in Example 1 of the present application under visible light is shown. V6O 11 Under direct visible light irradiation conditions, the photocatalytic performance of BQ, Na2C2O4, TBA (t-BuOH), and CuSO4 decreased by 22.44%, 14.29%, 6.90%, and 6.03%, respectively. This indicates that under direct visible light irradiation conditions, ·O2 - is the main active species, followed by h + , ·OH, and e - .

[0178] Figure 15 and Figure 16is the degradation curve and apparent rate constant of the catalyst prepared in Example 1 of the present application under near-infrared light for 40 mg / L tetracycline. After direct irradiation of near-infrared light for 90 min, the degradation rates of Example 1, Example 2, Example 3 and Comparative Example 1 for 40 mg / L TC were 92.49%, 61.54%, 60.09% and 83.04%, respectively. The apparent rate constants of each sample were 0.03556 min -1 (Comparative Example 1), 0.01355 min -1 (Example 2), 0.01235 min -1 (Example 3), and 0.02575 min -1 (Example 1), respectively. Figure 17 and Figure 18 is the TOC removal rate graph and cyclic degradation graph of the catalyst prepared in Example 1 of the present application under near-infrared light for 40 mg / L tetracycline. After direct irradiation of near-infrared light for 90 min, V6O 11 achieved a TOC removal rate of 80.13% for 40 mg / L TC, indicating that it also has excellent mineralization effect under near-infrared light. V6O 11 was subjected to four cycles of degradation under direct irradiation of near-infrared light, and the degradation rates were 92.71%, 92.50%, 92.25% and 89.07%, respectively. After four cycles of reaction, the degradation activity only decreased by 3.64%, and the reason for the decrease in activity may be due to the loss of a small amount of powder. It indicates that it has excellent cyclic stability under direct irradiation of near-infrared light.

[0179] Figure 19 is the active species capture graph of the catalyst prepared in Example 1 of the present application under near-infrared light. After adding BQ, Na2C2O4, TBA and CuSO4 under direct irradiation of near-infrared light, the degradation capacity of the photocatalyst decreased from 92.49% to 83.69%, 39.29%, 75.69% and 83.02%, respectively. h + is the main active species in the degradation process, while ·OH, ·O2 - and e - play a secondary role in the degradation process.

[0180] Figure 20 and Figure 21 is the infrared temperature imaging graph of the catalyst prepared in Example 1 of the present application under visible light and near-infrared light for 90 min for 40 mg / L tetracycline. The infrared thermal imager was used to observe the change of temperature during the degradation process to verify the photothermal effect of V6O 11 in the liquid phase. After direct irradiation of visible light / near-infrared light for 90 min, V6O 11The solution temperature is increased by about 32℃ / 38.2℃, respectively. It is proved that V6O 11 It not only has good photothermal performance under visible light, but also has excellent photothermal effect under near-infrared light.

[0181] Figure 22 is the degradation curve of 40mg / L tetracycline by the catalyst prepared in Example 1 of the present application under monochromatic light of 740nm, 850nm, 940nm and 1100nm. The degradation experiment is carried out under monochromatic light irradiation conditions, which further proves that V6O 11 It has degradation effect on TC in the full spectrum range. The degradation rates of 40mg / L TC after direct irradiation of monochromatic light of 740nm, 850nm, 940nm and 1100nm for 90min are 58.95%, 63.62%, 64.11% and 61.21%, respectively. It shows that V6O 11 It has enhanced photocatalytic degradation activity and practical application prospect on TC in the full spectrum.

[0182] Figure 23 and Figure 24 is the degradation rate graph of 20mg / L phenol, 20mg / L ciprofloxacin, 20mg / L salicylic acid, 20mg / L bisphenol A and 20mg / L coumarin by the catalyst prepared in Example 1 of the present application under visible light and near-infrared light. Figure 25 and Figure 26 is the TOC removal rate graph of 20mg / L phenol, 20mg / L ciprofloxacin, 20mg / L salicylic acid, 20mg / L bisphenol A and 20mg / L coumarin by the catalyst prepared in Example 1 of the present application under visible light and near-infrared light. The degradation rates of 20mg / L phenol, CIP, BHA, BPA and coumarin are 68.29%, 92.87%, 63.89%, 56.89% and 70.08%, respectively, after direct irradiation of visible light for 90min. The maximum degradation rates of phenol, CIP, BHA, BPA and coumarin are 61.43%, 82.39%, 61.63%, 48.92% and 69.98%, respectively, after direct irradiation of near-infrared light for 90min. It shows that V6O 11 It has excellent broad-spectrum degradation effect in the full spectrum range. After direct irradiation of visible light / near-infrared light for 90min, respectively, V6O 11 The TOC removal rates of phenol, CIP, BHA, BPA and coumarin reach 50.52% / 48.90%, 76.84% / 66.33%, 51.87% / 53.96%, 45.82% / 36.57% and 63.69% / 54.44%, respectively, which shows that V6O 11 It has good broad-spectrum mineralization ability in the full spectrum range.

[0183] Figure 27 and Figure 28 are the removal curves and apparent rate constants of the catalyst prepared in Example 1 of the present application for 40 mg / L tetracycline under dark conditions. After 90 min of dark reaction, the dark catalytic activity of Example 1 (87.82%) is significantly higher than that of Example 2 (52.06%), Example 3 (56.46%) and Comparative Example 1 (64.28%), and the degradation rates of Comparative Example 1, Example 2, Example 3 and Example 1 are 0.01477 min -1 , 0.00954 min -1 , 0.01105 min -1 and 0.02559 min -1 , respectively. Figure 29 and Figure 30 are the cyclic degradation graph and TOC removal rate graph of the catalyst prepared in Example 1 of the present application for 40 mg / L tetracycline under dark conditions after 16 cycles of light irradiation for 30 min followed by dark reaction. V6O 11 has a dark catalytic degradation activity for 40 mg / L TC for 16 cycles of reaction. With the extension of reaction time, the degradation rate gradually decreases, which is attributed to the consumption of stored electrons and holes and the loss of part of the powder. In addition, the TOC removal rates of V6O 11 for 40 mg / L TC during 1, 4, 7, 10, 13 and 16 cycles of reaction are 78.33%, 72.32%, 68.83%, 63.98%, 60.49% and 53.71%, respectively, indicating that V6O 11 also has a high mineralization capacity under dark conditions. However, the long-term dark catalytic activity and high mineralization capacity of V6O 11 can be restored after re-illumination, demonstrating that V6O 11 has good stability and repairability.

[0184] Figure 31 is the absorbance curve of the catalyst prepared in Example 1 of the present application for 70 mg / L methylene blue under dark conditions. The concentration of stored electrons in the sample is estimated by titration experiment of methylene blue, and the concentration of stored electrons in V6O 11 is 498.50 μmol·g -1 after conversion. Figure 32is the activity species capture diagram of the catalyst prepared in embodiment 1 of the present application in the dark. After introducing BQ, Na2C2O4, TBA and CuSO4 into the degradation reaction system in the dark, the degradation rate of 40 mg / L TC is reduced from 87.82% to 77.58%, 52.89%, 43.99% and 72.53% respectively, then, BQ and TBA are introduced into the system at the same time, the degradation rate is reduced by 12.10%, which proves that ·O2 - , h + , ·OH and e - all play a certain role during the dark reaction.

[0185] The present application utilizes the large amount of free electrons in V6O 11 and the large amount of holes generated by the variable valence of V metal existing in the material, at the same time, the strain formed by the mechanical stress disturbance generates the piezoelectric potential in V6O 11 and further forms the piezoelectric field, which greatly promotes the dark catalytic ability of the material to the extent comparable to the photocatalytic ability, and the material has good degradation ability for antibiotics tetracycline, ciprofloxacin, organic matter bisphenol A, salicylic acid, phenol and coumarin, and successfully prepares a material with excellent photocatalytic ability and high efficient dark catalytic ability.

[0186] The above only describes one embodiment of the present application, which is not all or only the embodiment, any equivalent transformation of the technical solution of the present application by the person skilled in the art through reading the specification of the present application is covered by the claims of the present application.

Claims

1. A Magnéli phase V6O 11 A method for preparing a piezoelectric catalyst, characterized in that, Includes the following steps: Step 1: Dissolve NH4VO3 in citric acid solution and stir until homogeneous to form precursor solution A; subject precursor solution A to hydrothermal reaction, separate the obtained product and wash and dry it to obtain powder NH4V3O8. The ratio of NH4VO3 to citric acid solution was (11.00~11.15) mmol: (20~30) mL, the concentration of citric acid solution was 0.50~0.55 mol / L, the hydrothermal reaction temperature was 100~120°C, and the reaction time was 10h~14h. Step 2: Dissolve VO2 powder and NH4V3O8 powder in a mixed solution of isopropanol and H2O, stir until homogeneous to form precursor solution B. Perform a hydrothermal reaction on precursor solution B, separate the resulting product, wash and dry it to obtain Magnéli phase V6O. 11 The piezoelectric catalyst has the following composition: the mass ratio of VO2 powder to NH4V3O8 powder is (2.5~3.5):1, the volume ratio of isopropanol to H2O is (11.5~13.5):(11.5~13.5), the hydrothermal reaction temperature is 180°C~200°C, and the reaction time is 0.5h~3.0h.

2. The Magnéli phase V6O according to claim 1 11 A method for preparing a piezoelectric catalyst, characterized in that, In step 2, the method for preparing VO2 powder is as follows: Vanadyl acetylacetonate is dissolved in a mixed solution of isopropanol and water, stirred to form a precursor solution; the precursor solution is subjected to a hydrothermal reaction, the precipitate is separated, washed and dried to obtain VO2 powder.

3. Magnéli phase V6O obtained by the preparation method according to any one of claims 1 to 2 11 Application of piezoelectric catalysts in the degradation of organic pollutants under dark or light conditions.

4. The application according to claim 3, characterized in that, The organic pollutant is an antibiotic or an organic compound, wherein the antibiotic is tetracycline or ciprofloxacin; and the organic compound is bisphenol A, salicylic acid, coumarin or phenol.

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