A preparation method of nitrogen and phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material for water treatment

Abstract

The application relates to a preparation method of a nitrogen-phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material for water treatment, in particular to the following steps: dispersing WO3 powder in water, mixing and dispersing glucose and phosphoric acid melamine in water, mixing the two aqueous solutions, putting foamed NiFe into the mixed solution, evaporating water under oil bath heating to form a slurry material, then putting the slurry material into a tube furnace, and roasting under an Ar atmosphere to obtain the nitrogen-phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material; and the application of the prepared nitrogen-phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material in a water treatment reaction.

Description

Technical Field

[0001] This invention relates to a method for preparing a nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material for water treatment, belonging to the field of material preparation and application. Background Technology

[0002] As a clean and renewable energy source, hydrogen energy is an ideal alternative to traditional fossil fuels, alleviating the pressure from carbon emissions. Among the reported hydrogen production pathways, electrocatalytic water splitting is an effective and clean method. Water electrolysis involves the oxygen evolution reaction at the anode and the hydrogen evolution reaction at the cathode. Compared to the hydrogen evolution reaction, the oxygen evolution reaction is a four-electron transfer process, so its kinetics are slow, making it the rate-controlling step in water electrolysis. In practical production, water electrolysis technologies include alkaline and acidic methods. Acidic water electrolysis has been studied more recently because this system can generate high current density, high voltage efficiency, and low impedance loss. However, low intrinsic activity and weak stability make water electrolysis under acidic conditions difficult to achieve. Therefore, developing efficient alkaline water electrolysis pathways has become an important research direction.

[0003] Studies have shown that constructing heterostructures can effectively increase the active surface area and efficiently catalyze water splitting. For example, Wang et al. constructed Ni3S4 / NiS2 / FeS2 heterostructured nanoparticles using ferric chloride hexahydrate, sodium diethyldithiocarbamate trihydrate, and nickel sulfate hexahydrate, achieving an electrocatalytic water splitting current density of 10 mA / cm² using 1M KOH as the electrolyte. 2 At that time, the voltage was 1.68V (Applied Surface Science 560(2021)149985). Feng et al. used Na2WO4·2H2O, C3H6N6, RuCl3·xH2O, and C4H 11 NO3, C8H 11 A Ru / WO3-W2N / NC electrolyte was constructed using NO2·HCl, and with 1M KOH as the electrolyte, the electrocatalytic hydrogen evolution current density was 10 mA / cm². 2 At that time, the overpotential was 64 mV; using 0.5 M H₂SO₄ as the electrolyte, the electrocatalytic hydrogen evolution current density was 10 mA / cm². 2 At that time, the overpotential was 110mV (Journal of Colloid and Interface Science 636(2023)618-62). Li et al. utilized Fe(NO3)3·9H2O, C3H6N6, RuCl3·xH2O, and C4H 11 NO3, C8H 11A Ru / Fe3O4-Fe3C / NC electrolyte was constructed using NO2·HCl, and with 1M KOH as the electrolyte, the electrocatalytic hydrogen evolution current density was 10 mA / cm². 2 At that time, the overpotential was 148 mV; using 0.5 M H₂SO₄ as the electrolyte, the electrocatalytic hydrogen evolution current density was 10 mA / cm². 2 At that time, the overpotential was 141 mV (International Journal of Hydrogen Energy 48(2023)15522-15532). In summary, constructing a nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material for catalytic water splitting is of great significance. Summary of the Invention:

[0004] This invention aims to provide a method for preparing a nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material for water treatment.

[0005] Based on the above objectives, the technical solution involved in this invention is as follows:

[0006] (1) Preparation of nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material: 0.1-0.2g of WO3 powder was dispersed in 15-25mL of water, 0.6-1.5g of glucose and 0.4-0.8g of melamine phosphate were mixed and dispersed in 15-25mL of water, and the two aqueous solutions were mixed. Foamed NiFe was added to the mixture, and the mixture was heated at 80-120℃ in an oil bath to evaporate the water and form a slurry. The slurry was then placed in a tube furnace and calcined at 500-700℃ for 1-2h under an Ar atmosphere to obtain the nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material. In the above preparation method, WO3 belongs to standard card JCPDS#43-1035; WP2 belongs to standard card JCPDS#35-1466.

[0007] (2) An application of the nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material prepared by the above preparation method in water treatment reactions; in the electrocatalytic splitting of water, the reaction current density is 10 mA / cm². 2 The voltage was 1.53-1.66V; for methylene blue in photocatalytic dye wastewater, the concentration of methylene blue was 0.1-1ppm, the reaction time was 8-10h, and the removal rate was 100%.

[0008] The present invention has the following advantages:

[0009] (1) A new synthetic route for nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material is provided.

[0010] (2) The nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material exhibits high catalytic activity in water treatment reactions. Attached image description:

[0011] Figure 1 The results are XRD characterization results of nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material.

[0012] Figure 2 These are the TEM and N, P, C, W, O mapping characterization results of the nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material. Detailed Implementation

[0013] The following examples are used to further illustrate the present invention, but are not intended to limit the invention.

[0014] Example 1

[0015] 0.1 g of WO3 powder was dispersed in 15 mL of water. 0.6 g of glucose and 0.4 g of melamine phosphate were mixed and dispersed in 15 mL of water. The two aqueous solutions were then mixed, and foamed NiFe was added to the mixture. The mixture was heated at 80°C in an oil bath to evaporate the water and form a slurry. The slurry was then placed in a tube furnace and calcined at 500°C for 1 hour under an Ar atmosphere to obtain a nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material. In the above preparation method, WO3 belongs to standard card JCPDS#43-1035; and WP2 belongs to standard card JCPDS#35-1466. An application of the nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material prepared by the above method in water treatment reactions; in electrocatalytic water splitting, the reaction current density is 10 mA / cm². 2 The voltage was 1.53V; the methylene blue concentration in the photocatalytic dye wastewater was 0.1ppm, the reaction time was 8h, and the removal rate was 100%.

[0016] Example 2

[0017] 0.2 g of WO3 powder was dispersed in 25 mL of water. 1.5 g of glucose and 0.8 g of melamine phosphate were mixed and dispersed in 25 mL of water. The two aqueous solutions were then mixed, and foamed NiFe was added to the mixture. The mixture was heated at 120 °C in an oil bath to evaporate the water and form a slurry. The slurry was then placed in a tube furnace and calcined at 700 °C for 2 hours under an Ar atmosphere to obtain a nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material. In the above preparation method, WO3 belongs to standard card JCPDS#43-1035; and WP2 belongs to standard card JCPDS#35-1466. An application of the nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material prepared by the above method is described; in the electrocatalytic decomposition of water, the reaction current density is 10 mA / cm². 2 The voltage was 1.66V; the methylene blue concentration in the photocatalytic dye wastewater was 1ppm, the reaction time was 10h, and the removal rate was 100%.

[0018] Example 3

[0019] 0.1 g of WO3 powder was dispersed in 20 mL of water. 1 g of glucose and 0.6 g of melamine phosphate were mixed and dispersed in 20 mL of water. The two aqueous solutions were then mixed, and foamed NiFe was added to the mixture. The mixture was heated at 100°C in an oil bath to evaporate the water and form a slurry. The slurry was then placed in a tube furnace and calcined at 600°C for 2 hours under an Ar atmosphere to obtain a nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material. In the above preparation method, WO3 belongs to standard card JCPDS#43-1035; and WP2 belongs to standard card JCPDS#35-1466. An application of the nitrogen-phosphorus co-doped carbon-encapsulated WO3-WP2 heterostructure material prepared by the above method in water treatment reactions; in electrocatalytic water splitting, the reaction current density is 10 mA / cm². 2 The voltage was 1.6V; the methylene blue concentration in the photocatalytic dye wastewater was 0.1ppm, the reaction time was 10h, and the removal rate was 100%.

Claims

1. A preparation method of nitrogen and phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material, characterized in that, comprising the steps of: Disperse 0.1-0.2 g WO3 powder in 15-25 mL water, mix and disperse 0.6-1.5 g glucose and 0.4-0.8 g melamine phosphate in 15-25 mL water, mix the two aqueous solutions, and put the foam NiFe into the mixed solution, heat to 80-120 o C evaporate water to form a slurry, then put the slurry into a tube furnace, and heat at 500-700 o C for 1-2 h to obtain a nitrogen and phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material; the WO3 belongs to standard card JCPDS #43-1035; and the WP2 belongs to standard card JCPDS #35-1466.

2. The application of nitrogen and phosphorus co-doped carbon encapsulated WO3-WP2 heterostructure material prepared by the preparation method of claim 1 in water treatment reaction; in electrocatalytic decomposition of water, the reaction current density is 10 mA / cm 2 , the voltage is 1.53-1.66 V; in the photocatalytic degradation of methylene blue in dye wastewater, the methylene blue concentration is 0.1-1 ppm, the reaction time is 8-10 h, and the removal rate is 100%.

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