Preparation and electrocatalytic application of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets

Abstract

The application relates to preparation of Ru-W2N nanosheet-nitrogen-doped carbon nanosheet and electrocatalytic application thereof, in particular to the following steps: dispersing m-WO3 nanosheet, tris(hydroxymethyl)aminomethane, dopamine hydrochloride and RuCl3 into water, drying, heating in an Ar atmosphere, obtaining W2N nanosheet encapsulated by nitrogen-doped carbon nanosheet, loading Ru nanoparticles on the nitrogen-doped carbon nanosheet, namely Ru-W2N nanosheet-nitrogen-doped carbon nanosheet, and application of the Ru-W2N nanosheet-nitrogen-doped carbon nanosheet in an electrocatalytic water reduction reaction.

Description

Technical Field

[0001] This invention relates to the preparation of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets and their electrocatalytic applications, belonging to the field of materials preparation and application. Background Technology

[0002] The escalating environmental pollution has compelled humanity to seek green energy sources. In the process of development, hydrogen energy has been found to have promising applications. While W₂N materials have been found to possess noble metal-like properties in traditional catalysis, their activity in electrocatalytic water reduction reactions is low. By modulating W₂N materials, Ru-W₂N nanosheets-nitrogen-doped carbon nanosheets were prepared, exhibiting more stable performance in electrocatalytic water reduction.

[0003] Methods such as morphology-controlled synthesis and material loading can effectively improve catalytic activity. For example, Zeng et al. used a multi-step method to achieve WO3 3-x W₂N heterostructured nanorods exhibit good lithium-ion battery performance, with a reversible capacity of 366.6 mAh / g at 0.1 A / g (Chemical Engineering Journal, 2022, 435, 135188). Xu et al. constructed W₂N / WC nanofibers, which possess high photoelectrocatalytic performance, with a current density of 50 mA / cm² at 495 mV. 2 (RSC Advances, 2021, 11, 20285-20291). Wu et al. synthesized a W2N nanorod-graphene composite hybrid material using WCl6 and graphene oxide (GO), which exhibited high electrocatalytic oxygen reduction performance with an initial electromotive force of 0.71 V (International Journal of Hydrogen Energy, 2017, 42, 25924-25932). In summary, changing the form of W2N can alter its catalytic performance, which has implications for the electrocatalytic hydrogen evolution reaction.

[0004] The search for new energy sources is an inevitable trend in national development. The synthesis of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets by anaerobic transformation exhibits stable catalytic activity in the electrocatalytic water reduction reaction, which has important practical significance. Summary of the Invention

[0005] This invention aims to provide the preparation of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets and their electrocatalytic applications.

[0006] Based on the above objectives, the technical solution involved in this invention is as follows:

[0007] (1) Preparation of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets: 20mg-40mg of m-WO3 nanosheets (JCPDS#43-1035) with a width of 90-320nm, 120-180mg of tris(hydroxymethyl)aminomethane, and 50-70mg of dopamine hydrochloride were dispersed in 50-70mL of ethanol and 50-70mL of water. After drying, they were dispersed with 20-40mg of RuCl3 in 50-70mL of water. After drying, they were ground and mixed with 150-190mg of melamine. The mixture was placed in a tube furnace and heated at 700-750℃ for 2-4h in an Ar atmosphere to obtain W2N nanosheets encapsulated with nitrogen-doped carbon nanosheets. Ru nanoparticles were loaded on the nitrogen-doped carbon nanosheets, i.e., Ru-W2N nanosheets-nitrogen-doped carbon nanosheets. In the above preparation method, the W2N nanosheets in the Ru-W2N nanosheet-nitrogen-doped carbon nanosheets are encapsulated by nitrogen-doped carbon nanosheets. The Ru particle size is 1-2 nm, the W2N nanosheet width is 70-350 nm, the nitrogen-doped carbon nanosheet size is 260-620 nm, and the W2N crystal phase belongs to standard card JCPDS#25-1257.

[0008] (2) Application of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets prepared by the above preparation method in electrocatalytic water reduction reaction; electrocatalytic water reduction reaction, using glassy carbon as electrode, in 1 mol / L KOH, voltage is 100-160.

[0009] The current density is 10 mA / cm² at mV. 2 In 0.5 mol / L H₂SO₄, the current density is 10 mA / cm² at a voltage of 100-200 mV. 2 .

[0010] The present invention has the following advantages:

[0011] 1) Using RuCl3, m-WO3 nanosheets, etc., a new synthetic route for Ru-W2N nanosheets-nitrogen-doped carbon nanosheets was developed by modulating the synthesis of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets prepared by thermal decomposition.

[0012] 2) Ru-W2N nanosheets-nitrogen-doped carbon nanosheets exhibit stable performance in the electrocatalytic water reduction reaction in both acidic and alkaline electrolytes. Attached Figure Description

[0013] Figure 1 The images show the XRD (a) and electron microscopy (b) characterization results of m-WO3 nanosheets (JCPDS#43-1035). Figure 2 The results are XRD and TEM characterizations of RRu-W2N nanosheets-nitrogen-doped carbon nanosheets. Detailed Implementation

[0014] The following examples are used to further illustrate the present invention, but are not intended to limit the invention.

[0015] Example 1

[0016] Preparation of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets and their electrocatalytic application: 20 mg of m-WO3 nanosheets (JCPDS#43-1035) with a width of 90-320 nm, 120 mg of tris(hydroxymethyl)aminomethane, and 50 mg of dopamine hydrochloride were dispersed in 50 mL of ethanol and 50 mL of water. After drying, they were dispersed with 20 mg of RuCl3 in 50 mL of water and dried. They were then ground and mixed with 150 mg of melamine and placed in a tube furnace. The mixture was heated at 700 °C for 2 h in an Ar atmosphere to obtain W2N nanosheets encapsulated with nitrogen-doped carbon nanosheets. Ru nanoparticles were loaded on the nitrogen-doped carbon nanosheets, i.e., Ru-W2N nanosheets-nitrogen-doped carbon nanosheets. The above preparation method involves W2N nanosheets encapsulated by nitrogen-doped carbon nanosheets in the RRu-W2N nanosheet-nitrogen-doped carbon nanosheets. The Ru particle size is 1-2 nm, the W2N nanosheet width is 70-350 nm, and the nitrogen-doped carbon nanosheet size is 260-620 nm. The W2N crystal phase is classified according to standard card JCPDS#25-1257. The Ru-W2N nanosheet-nitrogen-doped carbon nanosheets are applied in an electrocatalytic water reduction reaction. The application in the electrocatalytic water reduction reaction, using glassy carbon as an electrode, in 1 mol / L KOH, at a voltage of 100 mV, the current density is 10 mA / cm². 2 In 0.5 mol / L H₂SO₄, the current density is 10 mA / cm² at a voltage of 100 mV. 2 .

[0017] Example 2

[0018] Preparation of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets and their electrocatalytic application: 40 mg of m-WO3 nanosheets (JCPDS#43-1035) with a width of 90-320 nm, 180 mg of tris(hydroxymethyl)aminomethane, and 70 mg of dopamine hydrochloride were dispersed in 70 mL of ethanol and 70 mL of water. After drying, they were dispersed with 40 mg of RuCl3 in 70 mL of water and dried. They were then ground and mixed with 190 mg of melamine and placed in a tube furnace. The mixture was heated at 750 °C for 4 h in an Ar atmosphere to obtain W2N nanosheets encapsulated with nitrogen-doped carbon nanosheets. Ru nanoparticles were loaded on the nitrogen-doped carbon nanosheets, i.e., Ru-W2N nanosheets-nitrogen-doped carbon nanosheets. The above preparation method involves encapsulating W2N nanosheets with nitrogen-doped carbon nanosheets in the Ru-W2N nanosheet-nitrogen-doped carbon nanosheet configuration. The Ru particles have a size of 1-2 nm, the W2N nanosheets have a width of 70-350 nm, and the nitrogen-doped carbon nanosheets have a size of 260-620 nm. The W2N crystal phase is classified according to standard card JCPDS#25-1257. The Ru-W2N nanosheet-nitrogen-doped carbon nanosheets are applied in an electrocatalytic water reduction reaction. The application in the electrocatalytic water reduction reaction, using glassy carbon as an electrode, in 1 mol / L KOH, at a voltage of 160 mV, results in a current density of 10 mA / cm². 2 In 0.5 mol / L H₂SO₄, the current density is 10 mA / cm² at a voltage of 200 mV. 2 .

[0019] Example 3

[0020] Preparation of Ru-W2N nanosheets and their electrocatalytic application: 30 mg of m-WO3 nanosheets (JCPDS#43-1035) with a width of 90-320 nm, 160 mg of tris(hydroxymethyl)aminomethane, and 60 mg of dopamine hydrochloride were dispersed in 60 mL of ethanol and 60 mL of water. After drying, they were dispersed with 30 mg of RuCl3 in 60 mL of water and dried. They were then ground and mixed with 170 mg of melamine and placed in a tube furnace. The mixture was heated at 720 °C for 3 h in an Ar atmosphere to obtain W2N nanosheets encapsulated with nitrogen-doped carbon nanosheets. Ru nanoparticles were loaded on the nitrogen-doped carbon nanosheets, i.e., Ru-W2N nanosheets-nitrogen-doped carbon nanosheets. The above preparation method describes a Ru-W₂N nanosheet-nitrogen-doped carbon nanosheet process where W₂N nanosheets are encapsulated by nitrogen-doped carbon nanosheets. The Ru particles have a size of 1-2 nm, the W₂N nanosheets have a width of 70-350 nm, and the nitrogen-doped carbon nanosheets have a size of 260-620 nm. The W₂N crystal phase is classified according to standard card JCPDS#25-1257. The Ru-W₂N nanosheet-nitrogen-doped carbon nanosheets are applied in an electrocatalytic water reduction reaction. The application in the electrocatalytic water reduction reaction, using glassy carbon as an electrode, in 1 mol / L KOH, at a voltage of 150 mV, results in a current density of 10 mA / cm². 2 In 0.5 mol / L H₂SO₄, the current density is 10 mA / cm² at a voltage of 150 mV. 2 .

Claims

1. A method for preparing Ru-W2N nanosheets-nitrogen-doped carbon nanosheets, characterized in that, Includes the following steps: 20-40 mg m-WO3 nanosheets, 120-180 mg tris(hydroxymethyl)aminomethane, and 50-70 mg dopamine hydrochloride were dispersed in 50-70 mL of ethanol and 50-70 mL of water. After drying, this mixture was dispersed with 20-40 mg RuCl3 in 50-70 mL of water and dried. Then, it was ground and mixed with 150-190 mg melamine. The mixture was then placed in a tube furnace and heated at 700-750 °C under an Ar atmosphere. o Heating at C for 2-4 h yields W2N nanosheets encapsulated with nitrogen-doped carbon nanosheets. Ru nanoparticles are loaded onto the nitrogen-doped carbon nanosheets, i.e., Ru-W2N nanosheets-nitrogen-doped carbon nanosheets.

2. The preparation method according to claim 1, characterized in that, The m-WO3 nanosheets have a width of 90-320 nm, and the WO3 crystal phase is classified under standard card JCPDS#43-1035.

3. The preparation method according to claim 1, characterized in that, The Ru-W2N nanosheet-nitrogen-doped carbon nanosheets consist of nitrogen-doped carbon nanosheets that encapsulate W2N nanosheets. Ru nanoparticles with a size of 1-2 nm are loaded on the nitrogen-doped carbon nanosheets. The width of the W2N nanosheets is 70-350 nm, and the size of the nitrogen-doped carbon nanosheets is 260-620 nm. The W2N crystal phase is classified according to standard card JCPDS#25-1257.

4. The application of Ru-W2N nanosheets-nitrogen-doped carbon nanosheets prepared by the preparation method according to any one of claims 1-3 in the electrocatalytic water reduction reaction; using glassy carbon as an electrode, in 1 mol / L KOH, the current density is 10 mA / cm² at a voltage of 100-160 mV. 2 In 0.5 mol / L H₂SO₄, the current density is 10 mA / cm² at a voltage of 100-200 mV. 2 .

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