A Ni for water treatment 12 Preparation method of P5-Ni5P4 heterostructure / nitrogen-doped carbon

Abstract

The present invention relates to a Ni for water treatment 12 The preparation method of P5-Ni5P4 heterostructure / nitrogen-doped carbon material is as follows: chitosan is dispersed in ethanol, salicylaldehyde is added, and a yellow solid is obtained after reaction; the solid is mixed with ethanol and Ni(NO3)2·6H2O to obtain a solid powder; the powder is dispersed in ethanol, added dropwise to nickel-iron foam, reacted with NaH2PO2·H2O, and calcined under Ar atmosphere to obtain Ni 12 P5‑Ni5P4 heterostructure / nitrogen-doped carbon; the prepared Ni 12 Application of P5‑Ni5P4 heterostructure / nitrogen-doped carbon in water treatment reactions.

Description

Technical Field

[0001] The present invention relates to a Ni for water treatment 12 The invention discloses a preparation method of a P5-Ni5P4 heterostructure / nitrogen-doped carbon, belonging to the field of material preparation and application. Background Art

[0002] Water splitting batteries, metal-air batteries, fuel cells, etc. are considered to be environmentally friendly and effective technologies to meet global energy needs. In the application of water electrolysis for renewable energy, oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are two key electrochemical processes. To date, precious metal-based IrO2 and RuO2 are considered to be effective catalysts for OER, and Pt-based materials are used to catalyze HER. However, their scarcity and high price inhibit large-scale practical production. On the other hand, it is relatively difficult to use a single catalyst to catalyze both OER and HER. For example, transition metal phosphides, carbides, sulfides, etc. exhibit excellent acidic HER activity; transition metal oxides, hydroxides, etc. exhibit high OER activity. Therefore, the development of low-cost, highly active bifunctional catalysts is very urgent.

[0003] To overcome the above problems, people have made great efforts to improve the activity of oxygen evolution reaction and hydrogen evolution reaction. Jia's group used Co(CH3COO)2·4H2O, NaH2PO2·H2O, urea, etc. to synthesize CoP-g-C3N4 heterostructures. When catalyzing hydrogen evolution reaction, the reaction rate of this material was 959.4μmol / h / g (Journal of Colloid and Interface Science 599(2021)23-33). Tu's group used Co(NO3)2, NH4F, CO(NH2)2, etc. to hydrothermally synthesize Co2(OH)2CO3 nanowires at 120℃ for 10h; they calcined them at 500℃ for 2h under inert atmosphere to obtain CoO nanowires; then, the CoO nanowires were nitrided with NH3 at 300℃ for 2h to obtain N-CoO nanowires; this material was used to catalyze oxygen evolution reaction and found that the current density was 10mA / cm when the overpotential was 319mV. 2(Journal of Energy Chemistry 37(2019)13-17). Xing's group synthesized Ni(OH)2·0.75H2O nanodisks by hydrothermal treatment at 120°C for 5 h using Ni(ac)2·4H2O, NH4F, (NH2)2CO, and others. They then calcined the Ni(OH)2·0.75H2O nanodisks with NaH2PO2·H2O and S powder at 500°C for 1 h to synthesize S-Ni5P4 NPA / CP. They applied this catalyst to the hydrogen evolution reaction, finding that at an overpotential of 104 mV, the current density was 100 mA / cm 2 (ACS Applied Materials&Interfaces 10(2018)26303-26311). Therefore, we constructed Ni 12 P5-Ni5P4 heterostructure / nitrogen-doped carbon, which has good bifunctional catalytic activity. Summary of the Invention

[0004] The present invention aims to provide a Ni-based water treatment system for water treatment. 12 Preparation method of P5-Ni5P4 heterostructure / nitrogen-doped carbon.

[0005] Based on the above objectives, the technical solutions involved in the present invention are as follows:

[0006] (1)Ni 12 Preparation of P5-Ni5P4 heterostructure / nitrogen-doped carbon: 1-2g chitosan was dispersed in 50-100mL anhydrous ethanol, and 1-2g salicylaldehyde was added, and the mixture was reacted at 60-70℃ for 10-16h to obtain a yellow solid; 0.2-0.4g of the solid was mixed with 15-20mL ethanol and 0.5-0.6g Ni(NO3)2·6H2O, and the mixture was reacted at 80-120℃ for 8-12h to obtain a solid powder; the powder was dispersed in ethanol, added dropwise to the nickel-iron foam, and placed in a magnetic boat at the rear end of a tube furnace. 0.5-1g NaH2PO2·H2O was placed in another magnetic boat at the front end of the tube furnace, and calcined at 500-600℃ for 1-2h under Ar atmosphere to obtain Ni supported on nitrogen-doped carbon. 12 P5-Ni5P4 heterostructure material. The above preparation method, the Ni 12 P5 belongs to the standard card JCPDS#74-1381; the Ni5P4 belongs to the standard card JCPDS#18-0883.

[0007] (2) Ni prepared by the above-mentioned preparation method 12Application of P5-Ni5P4 heterostructure / nitrogen-doped carbon materials in water treatment reactions; in electrocatalytic water splitting, the reaction current density is 10mA / cm 2 , the voltage is 1.61-1.67V.

[0008] The present invention has the following advantages:

[0009] (1) Provides Ni 12 A new synthetic route for P5-Ni5P4 heterostructure / nitrogen-doped carbon materials.

[0010] (2)Ni 12 The P5-Ni5P4 heterostructure / nitrogen-doped carbon material exhibits high catalytic ability in water treatment reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It's Ni 12 XRD, SEM and Ni, P, C, N Mapping characterization results of P5-Ni5P4 heterostructure / nitrogen-doped carbon material. DETAILED DESCRIPTION

[0012] The following examples are intended to further illustrate the present invention but are not intended to limit the present invention.

[0013] Example 1

[0014] 1g chitosan was dispersed in 50mL anhydrous ethanol, and then 1g salicylaldehyde was added, and the mixture was reacted at 60℃ for 10h to obtain a yellow solid. 0.2g of the solid was mixed with 15mL ethanol and 0.5g Ni(NO3)2·6H2O, and the mixture was reacted at 80℃ for 8h to obtain a solid powder. The powder was dispersed in ethanol, added dropwise to the nickel-iron foam, and placed in a magnetic boat at the rear end of a tube furnace. 0.5g NaH2PO2·H2O was placed in another magnetic boat at the front end of a tube furnace, and calcined at 500℃ for 1h under Ar atmosphere to obtain Ni supported on nitrogen-doped carbon. 12 P5-Ni5P4 heterostructure material. The above preparation method, the Ni 12 P5 belongs to the standard card JCPDS#74-1381; the Ni5P4 belongs to the standard card JCPDS#18-0883. 12 Application of P5-Ni5P4 heterostructure / nitrogen-doped carbon materials in water treatment reactions; in electrocatalytic water splitting, the reaction current density is 10mA / cm 2 , the voltage is 1.61V.

[0015] Example 2

[0016] 2g of chitosan was dispersed in 100mL of anhydrous ethanol, and then 2g of salicylaldehyde was added, and the mixture was reacted at 70℃ for 16h to obtain a yellow solid. 0.4g of the solid was mixed with 20mL of ethanol and 0.6g of Ni(NO3)2·6H2O, and the mixture was reacted at 120℃ for 12h to obtain a solid powder. The powder was dispersed in ethanol, added dropwise to the nickel-iron foam, and placed in a magnetic boat at the rear end of a tube furnace. 1g of NaH2PO2·H2O was placed in another magnetic boat at the front end of a tube furnace, and calcined at 600℃ for 2h under Ar atmosphere to obtain Ni supported on nitrogen-doped carbon. 12 P5-Ni5P4 heterostructure material. The above preparation method, the Ni 12 P5 belongs to the standard card JCPDS#74-1381; the Ni5P4 belongs to the standard card JCPDS#18-0883. 12 Application of P5-Ni5P4 heterostructure / nitrogen-doped carbon materials in water treatment reactions; in electrocatalytic water splitting, the reaction current density is 10mA / cm 2 , the voltage is 1.67V.

[0017] Example 3

[0018] 1g chitosan was dispersed in 100mL anhydrous ethanol, and then 2g salicylaldehyde was added, and the mixture was reacted at 60℃ for 10h to obtain a yellow solid. 0.2g of the solid was mixed with 20mL ethanol and 0.6g Ni(NO3)2·6H2O, and the mixture was reacted at 80℃ for 12h to obtain a solid powder. The powder was dispersed in ethanol, added dropwise to the nickel-iron foam, and placed in a magnetic boat at the rear end of a tube furnace. 0.5g NaH2PO2·H2O was placed in another magnetic boat at the front end of a tube furnace, and calcined at 600℃ for 1h under Ar atmosphere to obtain Ni supported on nitrogen-doped carbon. 12 P5-Ni5P4 heterostructure material. The above preparation method, the Ni 12 P5 belongs to the standard card JCPDS#74-1381; the Ni5P4 belongs to the standard card JCPDS#18-0883. 12 Application of P5-Ni5P4 heterostructure / nitrogen-doped carbon materials in water treatment reactions; in electrocatalytic water splitting, the reaction current density is 10mA / cm 2 , the voltage is 1.65V.

Claims

1. A Ni 12 The preparation method of P5-Ni5P4 heterostructure / nitrogen-doped carbon material is characterized in that: The following steps are involved: Disperse 1-2 g of chitosan in 50-100 mL of anhydrous ethanol, add 1-2 g of salicylaldehyde, and react at 60-70° C. for 10-16 h to obtain a yellow solid; mix 0.2-0.4 g of the solid with 15-20 mL of ethanol and 0.5-0.6 g of Ni(NO3)2·6H2O, and react at 80-120° C. for 8-12 h to obtain a solid powder; disperse the powder in ethanol, add dropwise to the nickel-iron foam, place it in a porcelain boat, and place it at the rear end of a tube furnace; place 0.5-1 g of NaH2PO2·H2O in another porcelain boat and place it at the front end of the tube furnace; and heat at 500-600° C. under an Ar atmosphere. o C was calcined for 1-2 h to obtain Ni supported on nitrogen-doped carbon. 12 P5-Ni5P4 heterostructure material.

2. The preparation method according to claim 1, wherein The Ni 12 P5 belongs to the standard card JCPDS#74-1381; the Ni5P4 belongs to the standard card JCPDS#18-0883.

3. A Ni prepared by the preparation method according to any one of claims 1 to 2 12 Application of P5-Ni5P4 heterostructure / nitrogen-doped carbon materials in water treatment reactions for electrocatalytic water splitting with a reaction current density of 10 mA / cm 2 , the voltage is 1.61-1.67V.

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