Preparation method of rare earth doped conductive polymer@manganate
Rare earth-doped conductive polymers@manganate were prepared by hydrothermal method and in-situ chemical oxidative polymerization, which solved the problem of poor conductivity of manganate and achieved high conductivity and improved stability of the material, thus expanding its application in supercapacitors and photoelectrochemistry.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- UNIV OF SCI & TECH LIAONING
- Filing Date
- 2026-04-20
- Publication Date
- 2026-07-31
AI Technical Summary
Manganates have poor electrical conductivity, which affects their electrochemical performance and cycle stability. Existing technologies cannot improve their conductivity and stability through simple and environmentally friendly methods.
Rare earth-doped conductive polymers@manganate were prepared by hydrothermal method and in-situ chemical oxidation polymerization. The high conductivity of the conductive polymer and the 4f electron structure of rare earth elements were used to control the lattice defects of manganate to form a core-shell composite material.
It significantly improves the conductivity and cycle stability of the material, extends its service life, and enhances its electrochemical energy storage and photocatalytic performance, making it suitable for applications such as supercapacitors and photoelectrochemical hydrogen production.
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Figure CN122494471A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of rare earth doped modified composite material preparation technology, and particularly relates to a method for preparing rare earth doped regulated conductive polymer@manganate. Background Technology
[0002] Manganates, as important bimetallic oxides, possess multivalent redox properties, excellent ion insertion and extraction capabilities, and good electrocatalytic performance. They have unique applications in many functional materials, including battery cathode materials, solid electrolytes, magnetic functional materials, and potential supercapacitor electrode materials. Compared to traditional battery materials, manganate cathode materials exhibit significantly improved electrochemical performance. Furthermore, compared to single metal oxides, manganates, as binary metal oxides, possess advantages such as high redox activity, excellent rate performance, and cycle stability in electrochemical energy storage. However, the conductivity of manganate metal oxides needs improvement. Conductive polymers (polyacetylene, polyaniline, polythiophene, etc.), as cathode materials for supercapacitors, possess excellent conductivity and high pseudocapacitive activity, achieving efficient energy storage through rapid and reversible redox reactions. Recent studies have reported that doping modification to form oxygen vacancies and construct lattice defects can further effectively improve the photoelectric performance of materials. However, the unique 4f electronic structure characteristics of rare earth elements can further effectively improve the photoelectric performance of materials. Based on the above research, this study combined a conductive polymer with a manganate, which significantly improved the conductivity of the manganate, addressing its poor conductivity problem, and also markedly improved its cycle stability, thus greatly extending the material's lifespan. Furthermore, by doping the conductive polymer-manganate composite with a small amount of rare earth elements, the lattice defects were controlled, increasing the number of electrochemical active sites and enhancing the material's conductivity and rate performance. Simultaneously, the rare earth elements stabilized the crystal structure, preventing volume collapse during charge and discharge. Summary of the Invention
[0003] To overcome the shortcomings of existing technologies, the purpose of this invention is to provide a method for preparing rare earth-doped conductive polymer@manganate that is simple in process, low in cost, environmentally friendly, and produces products with excellent performance. This method utilizes the high conductivity of conductive polymers (such as polyaniline) to coat manganate, while simultaneously using the 4f electronic structure of rare earth elements to regulate the lattice defects and electronic states of manganate, thereby improving the conductivity and rate performance of the product, enhancing cycle stability, and expanding photocatalytic application performance.
[0004] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing rare earth-doped conductive polymer@manganate includes the following steps: 1) Mix lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate, then dissolve them in 30-1000 mL of deionized water and stir magnetically for 0.5-20 h until completely dissolved; adjust the pH of the system to 1-6 with dilute hydrochloric acid. 2) Transfer the mixed solution to a hydrothermal reactor and hydrothermally react at 80~220℃ for 3~96h; after the reaction is completed, cool naturally to room temperature, collect the product by centrifugation, wash with deionized water and anhydrous ethanol alternately 2~4 times, dry in a vacuum drying oven at 55~65℃ for 12~24h, and grind to obtain manganate powder. 3) Prepare 10-200 mL of 0.1-10 mol / L hydrochloric acid solution and cool it to 0-30℃ in an ice bath; add 0.001-10 mol of aniline monomer and stir until completely dissolved; add 0.05-20 g of the manganate obtained in step 2) and ultrasonically disperse for 0.5-6 h to make it uniformly suspended; 4) Prepare 5-150 mL of 0.01-20 mol / L ammonium persulfate solution and pre-cool it to 0-30℃; slowly add the ammonium persulfate solution dropwise to the aniline mixture obtained in step 3), keeping it in an ice bath and stirring throughout the process; after the addition is complete, stir the reaction in an ice bath for 0.5-72 h; after the reaction is complete, filter the mixture and wash it repeatedly with deionized water and ethanol until the filtrate is colorless; vacuum dry at 40-65℃ for 1.5-35 h to obtain the polyaniline@manganate composite material; 5) Sonicate the ITO conductive glass sequentially with acetone, ethanol, and deionized water for 10 min to 20 h each, then dry it with nitrogen or at low temperature. 6) Mix polyaniline@manganate composite material: acetylene black: polyvinylidene fluoride in a mass ratio of 8:1:1; dissolve polyvinylidene fluoride in N-methylpyrrolidone and stir until transparent, then add acetylene black and polyaniline@manganate composite material and stir until uniform; coat the obtained slurry uniformly on the conductive surface of ITO conductive glass; dry to remove NMP and moisture to obtain PANI / ITO@manganate working electrode.
[0005] The molar ratio of lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate in step 1) is (0.01~25):1:(0.1~30).
[0006] Step 5) Do not touch the conductive surface of the ITO conductive glass throughout the entire process.
[0007] Step 6) involves stirring until homogeneous for 4-6 hours.
[0008] Step 6) Active substance loading: 0.2~10 mg / cm³ 2 .
[0009] The drying process described in step 6) involves vacuum drying at 40-65°C for 5-24 hours.
[0010] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes a hydrothermal method and in-situ chemical oxidative polymerization to obtain rare-earth-doped conductive polymer@manganate materials. By controlling the reaction temperature, rare-earth-doped conductive polymer@manganate materials with controllable thickness, smooth surface, and controllable microstructure are obtained. The preparation process of this invention is simple, easy to operate, and exhibits good stability. Specifically: 1. This invention adopts a two-step method of "hydrothermal method + in-situ chemical oxidation polymerization", which does not require complex equipment and harsh conditions (such as high temperature and high pressure, inert gas protection) to achieve continuous preparation of rare earth doping and conductive polymer coating. The preparation process is safe and pollution-free, does not require expensive special equipment, and has a simple operation process with strong repeatability, making it suitable for large-scale and industrialized production.
[0011] 2. This invention utilizes rare earth element doping to stabilize the crystal framework of manganate, suppressing volume expansion and structural collapse during charge and discharge processes. Simultaneously, the conductive polymer shell acts as a buffer layer, mitigating stress changes caused by repeated redox reactions, thereby significantly extending the material's cycle life (capacity retention >90% after 10,000 cycles). This rare earth doping-controlled conductive polymer@manganate material exhibits tight core-shell bonding, structural stability, and better cycle stability.
[0012] 3. This invention utilizes the high conductivity of conductive polymers (such as polyaniline) to coat manganate, and at the same time, it uses the 4f electronic structure of rare earth elements to regulate the lattice defects and electronic states of manganate. The rare earth-doped conductive polymer@manganate material prepared has good conductivity in terms of electrochemical performance, which greatly improves the conductivity performance; it can still maintain a high capacity at high current density.
[0013] 4. The rare earth-doped regulated conductive polymer@manganate material prepared by this invention has both excellent electrochemical energy storage performance and photocatalytic degradation performance. It can be used as a multifunctional electrode / photocatalytic material and has been widely applied in fields such as supercapacitors, environmental remediation, and photoelectrochemical hydrogen production. Attached Figure Description
[0014] Figure 1 This is a graph showing the cyclic stability test results of the material in Example 1.
[0015] Figure 2 This is a constant current charge-discharge curve of the material in Example 1.
[0016] Figure 3 This is the cyclic voltammetry (CV) curve of the material in Example 1.
[0017] Figure 4 This is a graph showing the performance test curves of the material at high rate in Example 1.
[0018] Figure 5This is a graph showing the degradation of dye Rhodamine B by the material in Example 1.
[0019] Figure 6 This is the UV-Vis absorption spectrum of the material in Example 2 that photocatalytically degrades methyl orange.
[0020] Figure 7 This is a graph showing the performance test curves of the material at high rate in Example 2.
[0021] Figure 8 This is the Nyquist plot of the electrochemical impedance spectroscopy (EIS) of the material in Example 2.
[0022] Figure 9 This is a schematic diagram of the photocatalytic principle of the material in Example 3.
[0023] Figure 10 This is the UV-Vis absorption spectrum of the material in Example 3 that underwent photocatalytic degradation of methylene blue.
[0024] Figure 11 This is a graph showing the cyclic stability test results of the material in Example 3. Detailed Implementation
[0025] The present invention will now be described in detail with reference to the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments. Example 1:
[0026] The preparation method of the rare earth-doped conductive polymer@manganate material in this embodiment is carried out according to the following steps: 1) Lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate were prepared in proportions of 0.1 mol, 0.2 mol, and 0.2 mol, respectively. The prepared reagents were dissolved in 30 mL of deionized water and magnetically stirred for 1 h until completely dissolved. The pH of the system was adjusted to 1 with dilute hydrochloric acid. The mixed solution was transferred to a hydrothermal reactor and hydrothermally reacted at 100 °C for 24 h. After the reaction was completed, the mixture was allowed to cool to room temperature naturally, and the product was collected by centrifugation. The product was washed three times alternately with deionized water and anhydrous ethanol, and then dried in a vacuum drying oven at 60 °C for 12 h. The product was then ground to obtain manganate powder. 2) Prepare 10 mL of 0.1 mol / L hydrochloric acid solution and cool it to 0°C in an ice bath. Add 0.001 mol of aniline monomer and stir until completely dissolved. Add 0.05 g of the prepared manganate powder and sonicate for 0.5 h to ensure uniform suspension. Separately prepare 5 mL of 0.001 mol ammonium persulfate (APS) solution and pre-cool it to 0°C. Slowly add the APS solution dropwise to the aniline mixture while maintaining an ice bath and stirring throughout the process. After the addition is complete, stir the mixture in an ice bath for 6 h. After the reaction is complete, filter the solution and wash it repeatedly with deionized water and ethanol until the filtrate is colorless. Dry the filtrate under vacuum at 60°C for 12 h to obtain the polyaniline@manganate composite material. 3) Sonicate the ITO sequentially with acetone, ethanol, and deionized water for 15 minutes each. Dry it with nitrogen or at low temperature to ensure the surface is clean and free of oil. Set aside (avoid touching the conductive surface of the ITO throughout the process). Then, prepare the active material according to the mass ratio of PANI@manganate:acetylene black:PVDF = 8:1:1 obtained in step 2. Dissolve the PVDF in NMP first and stir until transparent. Add the acetylene black and active material, and stir for 4–6 hours until homogeneous. Apply the slurry evenly to the conductive surface of the ITO using drop coating, scraping, or spin coating. Control the active material loading at 0.2 mg / cm³. 2 Vacuum drying at 60℃ for 12 hours removes NMP and moisture. This yields a PANI / ITO@manganate working electrode (positive electrode material for supercapacitors).
[0027] The obtained supercapacitor positive electrode material was subjected to performance testing. For example... Figure 1 The results show the material's cycling stability. After 10,000 cycles at a current density of 1 A / g, the specific capacitance decreased from 465 F / g to 449 F / g, while the cycling stability remained at 96.6%, demonstrating excellent cycling stability. Figure 2 The charge-discharge capability of the electrode material at different current densities was demonstrated. This electrode material exhibits long charge-discharge time and high capacity at low current densities, indicating potential energy storage. Furthermore, its charge-discharge curve is relatively smooth, showing good electrochemical reversibility. CV curve testing was performed using… Figure 3 It can be seen that the CV curves of this electrode material at different scan rates show clear and symmetrical redox peaks, and the peak current increases linearly with the scan rate, exhibiting excellent rate performance, good electrochemical reversibility, and fast reaction kinetics. Figure 4 It can be seen that the electrode material achieves a specific capacitance of over 1400 F / g at a low current density of 1 A / g, demonstrating good energy storage capacity. Even at a high current density of 20 A / g, it maintains a specific capacitance of approximately 700 F / g, indicating that the material has a certain capacity retention capability at high rates. When the current density is switched from 15 A / g back to 1 A / g, the specific capacitance rebounds significantly to near its peak value; upon switching back to 10 A / g, it also recovers to its initial level, demonstrating good electrochemical reversibility.
[0028] See Figure 5 The material photocatalytically degrades the dye Rhodamine B. The gradually decreasing values in the UV-Vis spectrum indicate that the organic dye has been degraded. Example 2:
[0029] The preparation method of the nickel manganate / ITO composite thin material in this embodiment is carried out according to the following steps: 1) Lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate were prepared in proportions of 0.25 mol, 0.5 mol, and 0.25 mol, respectively. The prepared reagents were dissolved in 500 mL of deionized water and magnetically stirred for 10 h until completely dissolved. The pH of the system was adjusted to 3 with dilute hydrochloric acid. The mixed solution was transferred to a hydrothermal reactor and hydrothermally reacted at 120 °C for 48 h. After the reaction was completed, the mixture was allowed to cool to room temperature naturally, and the product was collected by centrifugation. The product was washed three times alternately with deionized water and anhydrous ethanol, and then dried in a vacuum drying oven at 60 °C for 12 h. The product was then ground to obtain manganate powder. 2) Prepare 100 mL of 0.05 mol / L hydrochloric acid solution and cool it to 20°C in an ice bath. Add 5 mol of aniline monomer and stir until completely dissolved. Add 10 g of the prepared manganate powder and ultrasonically disperse for 4 h to ensure uniform suspension. Separately prepare 100 mL of 0.01 mol / L ammonium persulfate (APS) solution and pre-cool it to 20°C. Slowly add the APS solution dropwise to the aniline mixture, maintaining an ice bath and stirring throughout the process. After the addition is complete, stir the reaction in an ice bath for 6 h. After the reaction is complete, filter the solution and wash it repeatedly with deionized water and ethanol until the filtrate is colorless. Dry the solution under vacuum at 60°C for 12 h to obtain the manganate@polyaniline composite material. 3) Sonicate the ITO sequentially with acetone, ethanol, and deionized water for 15 minutes each. Dry it with nitrogen or at low temperature to ensure the surface is clean and free of oil. Set aside (avoid touching the conductive surface of the ITO throughout the process). Then, prepare the active material according to the mass ratio of PANI@manganate:acetylene black:PVDF = 8:1:1 obtained in step 2. Dissolve the PVDF in NMP first and stir until transparent. Add the acetylene black and active material, and stir for 4–6 hours until homogeneous. Apply the slurry evenly to the conductive surface of the ITO using drop coating, scraping, or spin coating. Control the active material loading at 5 mg / cm³. 2 Vacuum drying at 60℃ for 12 hours removes NMP and moisture, yielding a PANI@manganate / ITO working electrode.
[0030] Depend on Figure 6 It can be seen that, using PANI@manganate / ITO working electrode as photocatalyst, under simulated illumination conditions, the characteristic absorption peak of methyl orange continuously decreases with the extension of illumination time, and the characteristic absorption peak almost completely disappears after 80 minutes of illumination, indicating that the composite material has excellent photocatalytic degradation performance for methyl orange. The results of dark adsorption for 1 hour confirm that the material has a moderate adsorption capacity for pollutants and has reached adsorption equilibrium, eliminating the interference of adsorption on the evaluation of photocatalytic performance. Figure 7 The rate performance test curves show that the specific capacitance of the material can still reach 2200F / g at low current densities of 1A / g and 3A / g, demonstrating excellent energy storage capacity. Even at a high current density of 12A / g, the specific capacitance can still be maintained at around 1700F / g, indicating that the material has excellent rate performance. Figure 8 It is an electrochemical impedance spectroscopy, which has low initial charge transfer impedance and smooth ion diffusion. However, after 5500 long cycles, the impedance spectrum morphology is intact, the core electrochemical structure is stable, and it has excellent initial reaction kinetics and structural tolerance. Example 3:
[0031] The preparation method of the nickel manganate / ITO composite material in this embodiment is carried out according to the following steps: 1) Lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate were prepared in proportions of 0.3 mol, 0.2 mol, and 0.3 mol, respectively. The prepared reagents were dissolved in 1000 mL of deionized water and magnetically stirred for 20 h until completely dissolved. The pH of the system was adjusted to 6 with dilute hydrochloric acid. The mixed solution was transferred to a hydrothermal reactor and hydrothermally reacted at 220 °C for 96 h. After the reaction was completed, the mixture was allowed to cool to room temperature naturally, and the product was collected by centrifugation. The product was washed three times alternately with deionized water and anhydrous ethanol, and then dried in a vacuum drying oven at 60 °C for 12 h. The product was then ground to obtain manganate powder. 2) Prepare 200 mL of 10 mol / L hydrochloric acid solution and cool it to 30°C in an ice bath. Add 10 mol of aniline monomer and stir until completely dissolved. Add 20 g of the prepared manganate and sonicate for 6 h to ensure uniform suspension. Separately prepare 150 mL of 0.01 mol / L ammonium persulfate (APS) solution and pre-cool it to 30°C. Slowly add the APS solution dropwise to the aniline mixture while maintaining an ice bath and stirring throughout the process. After the addition is complete, stir the reaction in an ice bath for 6 h. After the reaction is complete, filter the solution and wash it repeatedly with deionized water and ethanol until the filtrate is colorless. Dry the solution under vacuum at 60°C for 12 h to obtain the polyaniline@manganate composite material. 3) Sonicate the ITO sequentially with acetone, ethanol, and deionized water for 15 minutes each. Dry it under nitrogen or at low temperature to ensure the surface is clean and free of oil. Set aside (avoid touching the conductive surface of the ITO throughout the process). Prepare the active material (PANI@manganate):acetylene black:PVDF in a mass ratio of 8:1:1. Dissolve the PVDF in NMP first and stir until transparent. Add the acetylene black and active material, and stir for 4-6 hours until homogeneous. Apply the slurry evenly to the conductive surface of the ITO using drop coating, scraping, or spin coating. Control the active material loading at 10 mg / cm³. 2 Vacuum drying at 60℃ for 12 hours removes NMP and moisture, yielding a PANI / ITO@manganate working electrode.
[0032] Nickel manganese oxide / ITO composite photocatalytic materials combine the excellent visible light photocatalytic activity of nickel manganese oxide with the high conductivity, high light transmittance, and structural stability of the ITO substrate. This effectively promotes the separation and transport of photogenerated carriers, reduces recombination rates, and possesses advantages such as uniform film formation, good stability, and recyclability. It shows promising application prospects in photocatalytic degradation of pollutants, photoelectrochemical hydrogen production, and environmental remediation. For example... Figure 9 This is a basic schematic diagram of photocatalysis (photocatalytic degradation of dyes experiment). Figure 10 The results show that, using nickel manganate / ITO as a photocatalyst, under simulated illumination conditions, the characteristic absorption peak of methylene blue continuously decreases with prolonged illumination time, and the characteristic absorption peak weakens significantly after 25 minutes of illumination, indicating that the composite material has good photocatalytic degradation performance for methylene blue. The results of 1 hour of dark adsorption confirm that the material has a moderate adsorption capacity for the pollutant and has reached adsorption equilibrium, eliminating the interference of adsorption on the evaluation of photocatalytic performance. Figure 11 The graph shows the cycle stability test results. After 3000 cycles at a current density of 3A / g, the specific capacitance decreased from 1874F / g to 1735F / g, maintaining a high cycle stability of 92.6%.
Claims
1. A method for preparing rare earth-doped conductive polymer@manganate, characterized in that, Includes the following steps: 1) Mix lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate, then dissolve them in 30-1000 mL of deionized water and stir magnetically for 0.5-20 h until completely dissolved; adjust the pH of the system to 1-6 with dilute hydrochloric acid. 2) Transfer the mixed solution to a hydrothermal reactor and hydrothermally react at 80~220℃ for 3~96h; after the reaction is completed, cool naturally to room temperature, collect the product by centrifugation, wash with deionized water and anhydrous ethanol alternately 2~4 times, dry in a vacuum drying oven at 55~65℃ for 12~24h, and grind to obtain manganate powder. 3) Prepare 10-200 mL of 0.1-10 mol / L hydrochloric acid solution and cool it to 0-30℃ in an ice bath; add 0.001-10 mol of aniline monomer and stir until completely dissolved; add 0.05-20 g of the manganate obtained in step 2) and ultrasonically disperse for 0.5-6 h to make it uniformly suspended; 4) Prepare 5-150 mL of 0.01-20 mol / L ammonium persulfate solution and pre-cool it to 0-30℃; slowly add the ammonium persulfate solution dropwise to the aniline mixture obtained in step 3), keeping it in an ice bath and stirring throughout the process; after the addition is complete, stir the reaction in an ice bath for 0.5-72 h; after the reaction is complete, filter the mixture and wash it repeatedly with deionized water and ethanol until the filtrate is colorless; vacuum dry at 40-65℃ for 1.5-35 h to obtain the polyaniline@manganate composite material; 5) Sonicate the ITO conductive glass sequentially with acetone, ethanol, and deionized water for 10 min to 20 h each, then dry it with nitrogen or at low temperature. 6) Mix polyaniline@manganate composite material: acetylene black: polyvinylidene fluoride in a mass ratio of 8:1:1; dissolve polyvinylidene fluoride in N-methylpyrrolidone and stir until transparent, then add acetylene black and polyaniline@manganate composite material and stir until uniform; coat the obtained slurry uniformly on the conductive surface of ITO conductive glass; dry to remove NMP and moisture to obtain PANI / ITO@manganate working electrode.
2. The method for preparing a rare-earth-doped regulated conductive polymer@manganate according to claim 1, characterized in that, The molar ratio of lanthanum nitrate hexahydrate, nickel nitrate hexahydrate, and manganese nitrate tetrahydrate in step 1) is (0.01~25):1:(0.1~30).
3. The method for preparing a rare earth-doped regulated conductive polymer@manganate according to claim 1, characterized in that, Step 5) Do not touch the conductive surface of the ITO conductive glass throughout the entire process.
4. The method for preparing a rare-earth-doped regulated conductive polymer@manganate according to claim 1, characterized in that, Step 6) involves stirring until homogeneous for 4-6 hours.
5. The method for preparing a rare-earth-doped regulated conductive polymer@manganate according to claim 1, characterized in that, Step 6) Active substance loading 0.2 to 10 mg / cm 2 .
6. The method for preparing a rare-earth-doped regulated conductive polymer@manganate according to claim 1, characterized in that, The drying process described in step 6) involves vacuum drying at 40-65°C for 5-24 hours.