阅读说明：本技术 一种利用水熔盐法在基底上生长一维纳米棒状结构材料的方法 (Method for growing one-dimensional nano rod-shaped structure material on substrate by using water molten salt method ) 是由 雷鸣 黄凯 毕科 郭帅 吴宇峰 于 2020-04-20 设计创作，主要内容包括：本发明涉及一种利用水熔盐法在基底(泡沫镍、钢网、钛网、钼网、碳纤维布等)上生长一维纳米棒状结构材料的方法,属于材料科学与工程技术和化学领域。本发明制备的一维纳米棒状结构材料涉及的金属有Ni、Co、Fe、Mn、Cu、Mo、W、Nb、Ru、Rh、Pd等元素。首先,把一定量的化学试剂A和B溶入一定量的去离子水中,配置成一定浓度的反应物溶液C,再把事先清洗干净的基底浸入上述溶液C中,然后在一定温度下加热数个小时得到最终产物。本方法具有操作简单、效率高、应用范围广等优点。(The invention relates to a method for growing a one-dimensional nano rod-shaped structure material on a substrate (such as foamed nickel, a steel mesh, a titanium mesh, a molybdenum mesh, carbon fiber cloth and the like) by using a water molten salt method, belonging to the field of material science, engineering technology and chemistry. The metal related to the one-dimensional nano rod-shaped structure material prepared by the invention comprises elements such as Ni, Co, Fe, Mn, Cu, Mo, W, Nb, Ru, Rh, Pd and the like. Firstly, dissolving a certain amount of chemical reagents A and B into a certain amount of deionized water to prepare a reactant solution C with a certain concentration, then soaking a substrate cleaned in advance into the reactant solution C, and then heating for a plurality of hours at a certain temperature to obtain a final product. The method has the advantages of simple operation, high efficiency, wide application range and the like.)

1. The invention relates to a method for growing a one-dimensional nano rod-shaped structure material on a substrate (foamed nickel, steel mesh, titanium mesh, molybdenum mesh, carbon fiber cloth and the like) by using a water molten salt method, which is characterized by comprising the following steps of:

(1) respectively cleaning substrates such as foamed nickel and the like by using acetone, alcohol, diluted hydrochloric acid and deionized water, and removing impurities such as grease, oxides and the like on the surfaces of the substrates;

(2) dissolving a certain amount of nitrate chemical reagent A into deionized water, then adding a small amount of chemical reagent B into the solution, uniformly stirring, and finally transferring the solution into a round-bottom conical flask;

(3) putting the substrate such as the foam nickel prepared in advance in the step (1) into the solution (2), then putting the round-bottom conical flask into a blast drying oven, heating for tens of hours under a certain temperature condition, and after the reaction is finished, performing ultrasonic treatment for 1min by using deionized water and cleaning.

(2) Field of the invention

The invention relates to a method for growing a one-dimensional nano rod-shaped structure material on a substrate by using a water molten salt method, belonging to the field of material science, engineering technology and chemistry.

(3) Background of the invention

Hydrogen energy is considered one of the cleanest, most promising sustainable energy sources, and electrochemical water splitting is an effective method for large-scale hydrogen production in the prior art. The whole water splitting process comprises two half reactions: a Hydrogen Evolution Reaction (HER) at the cathode and an Oxygen Evolution Reaction (OER) at the anode. Noble metals Pt and IrO₂(or RuO)₂) Have been identified as the most active electrocatalysts for HER and OER, respectively. However, their high cost, scarcity and poor stability have hindered their large-scale use. Therefore, current research is mainly focused on developing electrocatalysts having high catalytic activity and low cost. To date, the HER properties of phosphides, sulphides, carbides and nitrides of some transition metal compounds, and the OER properties of oxides, nitrides and hydroxides have been reported. However, the catalytic activity of these electrocatalysts needs to be further improved, since most of the above mentioned electrocatalysts cannot be used for bifunctional electrocatalysis of HER and OER in the same electrolyte.

For the preparation of electrodes, most people use binders such as polyvinylidene fluoride (PVDF) and Nafion to attach and fix an electrocatalyst to a current collector for electrochemical performance testing. However, the adhesive hinders the contact of the active site with the electrolyte, resulting in a decrease in electrical conductivity, thereby inhibiting the catalytic performance of the electrocatalyst. In addition, at high current densities, the catalyst on the electrode may be susceptible to delamination, resulting in poor catalytic stability. One key and effective strategy to address these problems is to grow electrocatalysts directly on conductive substrates, such as Carbon Fiber Cloth (CFC) and Nickel Foam (NF) substrates.

Basic salts such as metal carbonate hydroxides and metal nitrate hydroxides have attracted much attention because of their excellent electrocatalytic properties, especially nitrate compounds. Metal nitrate hydroxides have shown great potential in OER performance, but their performance in HER is not very good. From the thermodynamic and kinetic perspectives, the problem of insufficient performance of the nitrate solution in the aspect of HER can be effectively solved by adding a small amount of elements such as high-valence Mo, W, Nb, Ru, Rh, Pd and the like into the nitrate solution, and the OER performance of the nitrate solution is also improved greatly. In addition, metal nitrates generally possess a relatively low melting point and can be converted to nitrate hydroxide by a mild self-decomposition process.

(4) Summary of the invention

1. Objects of the invention

The invention aims to provide a method for growing a one-dimensional nanorod structure material on a substrate by using a water molten salt method. A small amount of high-valence ammonium salt such as Mo, W, Nb, Ru, Rh, Pd and the like is added into nitrate solution of elements such as Ni, Co, Fe, Mn, Cu and the like, and a one-dimensional nano rod-shaped structure material is grown on a substrate such as foamed nickel and the like by a water molten salt method. The material shows excellent electrochemical performance in terms of OER and HER. In addition, the material is found to have stable electrochemical catalytic performance by measuring the time-current and CV curve of the material.

2. The invention of the technology

The key points of the invention are as follows:

(1) preparing a reactant solution A with the mass-volume concentration of 0.1-0.2 g/ml by using a metal nitrate solution and a solvent, pouring the solution into a round-bottom conical flask, wherein the metal nitrate elements are Ni, Co, Fe, Mn and Cu, and the solvent is deionized water.

(2) Adding 0.2-0.3 g of high-valence metal ammonium salt into the solution A, and carrying out ultrasonic treatment on the solution by using an ultrasonic water tank until the solution is in a non-precipitation state, wherein the high-valence metal ammonium salt is Mo, W, Nb, Ru, Rh or Pd.

(3) Putting the round-bottom conical flask into a forced air drier, and heating for 20min at a certain temperature; then putting the cleaned substrate into the round-bottom conical flask, and heating for a certain time at the same temperature, wherein the reaction temperature is 65-125 ℃, and the reaction time is 0.3-10 h.

The method for growing the one-dimensional nano rod-shaped structure material on the substrate by using the water molten salt method has the advantages that: the method has wide application range, can synthesize multi-metal materials such as Ni, Co, Fe, Mn, Cu and the like, is also suitable for various substrates such as foamed nickel, titanium mesh, steel mesh, nickel mesh, carbon fiber cloth and the like, and the synthesized material has firm structure, good heat conductivity and electric conductivity, stable chemical property and simple synthesis process and can be applied to large-scale production.

(5) Attached drawings of the invention

In FIG. 1 a and b are respectively scanning and transmission electron microscope images of the material prepared by the method of the present invention.

(6) Examples of the invention

The following describes embodiments of the method of the invention:

example 1

Preparation of Ni-Mo/NF

Fully mixing nickel nitrate hexahydrate and deionized water to prepare a mixed solution A of 0.167g/ml, pouring the mixed solution A into a round-bottom conical flask, adding a small amount of ammonium molybdate tetrahydrate into the round-bottom conical flask, and putting the conical flask into an ultrasonic water tank for ultrasonic treatment until the solution has no precipitate; then putting the round-bottom conical flask into a forced air drier, heating to 125 ℃, preserving the heat for 20min, putting the cleaned foam nickel with certain size into the round-bottom conical flask, and finally heating for 10h at 125 ℃. And after the reaction is finished, cleaning chemical reagents which do not react on the surface of the foamed nickel by using deionized water, and drying in a vacuum drying oven.