阅读说明：本技术 一种片状半金属MoTe2:Cu和片状半金属MoTe2:Cu/RGO的制备方法 (Flaky semimetal MoTe2Cu and flaky semi-metal MoTe2Preparation method of Cu/RGO ) 是由 贺海燕 贺祯 沈清 于 2019-09-29 设计创作，主要内容包括：本发明公开了一种片状半金属MoTe_2:Cu和片状半金属MoTe_2:Cu/RGO的制备方法,将碲粉和硼氢酸钾加入到去离子水中并置于密封环境反应,得Te~(2-)前驱体水溶液；将仲钼酸铵和醋酸铜加入到10ml溶剂中溶解后加入柠檬酸,得钼离子源前驱体溶液；将Te~(2-)前驱体水溶液和钼离子源前驱体溶液置入反应釜中室温下保持后梯度升温至155～165℃水热反应,冷却至室温,过滤并对过滤物清洗后干燥,得Cu离子掺杂的片状半金属二碲化钼和Cu离子掺杂的片状半金属二碲化钼与石墨烯的复合物。其能够直接生产半金属结构的金属二碲化钼且其制备工艺简单。(The invention discloses a flaky semi-metal MoTe 2 Cu and flaky semi-metal MoTe 2 the preparation method of Cu/RGO comprises adding tellurium powder and potassium borohydride into deionized water, and reacting in sealed environment to obtain Te 2‑ a precursor aqueous solution; adding ammonium paramolybdate and copper acetate into 10ml of solvent for dissolving, and then adding citric acid to obtain a precursor solution of a molybdenum ion source; mixing Te 2‑ Placing the precursor aqueous solution and the molybdenum ion source precursor solution into a reaction kettle, keeping the temperature at room temperature, heating the solution to 155-165 ℃ in a gradient manner for hydrothermal reaction, cooling the solution to room temperature, filtering the solution, cleaning the filtered substance, and drying the filtered substance to obtain Cu ion-doped flaky semimetal molybdenum ditelluride and Cu ion-doped flaky semimetal molybdenum ditellurideA complex of a heterolamellar semimetal molybdenum ditelluride and graphene. The method can directly produce the molybdenum ditelluride with the semi-metal structure and has simple preparation process.)

1. Flaky semimetal MoTe₂cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized by comprising the following steps:

Step 1: adding 0.002-0.004 mol of tellurium powder and 0.004-0.008 mol of potassium borohydride into 10ml of deionized water, placing the mixture in a sealed environment for reaction to obtain Te^2-A precursor aqueous solution;

Step 2: adding 0.001/7 multiplied by 0.965-0.002/7 multiplied by 0.965mol of ammonium paramolybdate and 0.000005-0.00001 mol of copper acetate into 10ml of solvent for dissolving, and then adding 0.0025-0.005 mol of citric acid to obtain a precursor solution of the molybdenum ion source;

And step 3: mixing Te^2-placing the precursor aqueous solution and the molybdenum ion source precursor solution into a reaction kettle, keeping the solution at room temperature, performing gradient heating to 155-165 ℃ for hydrothermal reaction, cooling to room temperature, filtering, cleaning the filtered substance, and drying to obtain sheet-shaped semi-metal MoTe₂Cu and flaky semi-metal MoTe₂:Cu/RGO。

2. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized in that the mass ratio of the tellurium powder to the potassium borohydride in the step 1 is 1: 2.

3. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂the preparation method of the Cu/RGO is characterized in that the reaction time in the step 1 is 40-50 h.

4. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized in that the solvent in the step 2 is deionized water.

5. The sheet metal half-metal MoTe according to claim 4₂Cu and flaky semi-metal MoTe₂The preparation method of Cu/RGO is characterized in that the solvent in the step 2 is a 1mg/ml graphene oxide aqueous solution.

6. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized in that the time of keeping at room temperature in the step 3 is 10-12 h.

7. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized in that in the step 3, the temperature is raised to 45-55 ℃ and kept for 4-5 h, then the temperature is raised to 95-105 ℃ and kept for 3-4 h, and then the temperature is raised to 155-165 ℃ for hydrothermal reaction for 15-17 h.

8. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized in that the heating rate of the gradient temperature rise in the step 3 is 10-40 ℃/min.

9. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO is characterized in that deionized water and ethanol are adopted for cleaning in the step 3.

10. Sheet-like semimetal MoTe according to claim 1₂Cu and flaky semi-metal MoTe₂The preparation method of Cu/RGO is characterized in that the drying in the step 3 is drying at 50-60 ℃ for 12-14 h.

Technical Field

The invention belongs to the technical field of electrocatalysts, and relates to a flaky semi-metal MoTe₂Cu and flaky semi-metal MoTe₂The preparation method of Cu/RGO.

background

Hydrogen is a clean energy source and is currently receiving wide attention. Electrocatalytic water is currently one of the most efficient methods for producing hydrogen.MoTe₂the catalyst is an ideal electrocatalyst due to excellent photoelectric properties. MoTe₂Generally, there are three structures of semiconductor, metal and semimetal. The semiconductor and the semi-metal structure are stable, and the semi-metal structure and the metal structure have excellent photoelectric properties, particularly high conductivity; in order to meet the requirements of higher hydrogen production performance and long-term stability of electrocatalysis, MoTe with a semi-metal structure is selected at present₂While for strengthening the semimetal MoTe₂The conductive property and hydrogen evolution catalytic property of (1), which is generally in the synthesis of MoTe₂Single layer of half metal MoTe with metal ions doped in it, currently doped with metal ions₂It is generally necessary to first synthesize a bulk semiconductor structure MoTe doped with metal ions₂Then, various complicated chemical and physical layering methods are applied to layer the semi-metal sheets into the semi-metal sheets, and the process is complicated. Meanwhile, the sheet single-layer MoTe doped with metal ions is obtained by the currently applied layering method₂Still a semiconductor structure or a hybrid structure of semiconductor and semi-metal.

Disclosure of Invention

The invention aims to provide a flaky semimetal MoTe with simple process₂Cu and flaky semi-metal MoTe₂The preparation method of Cu/RGO.

The invention is realized by the following technical scheme:

Flaky semimetal MoTe₂Cu and flaky semi-metal MoTe₂The preparation method of the Cu/RGO comprises the following steps:

Step 1: adding 0.002-0.004 mol of tellurium powder and 0.004-0.008 mol of potassium borohydride into 10ml of deionized water, placing the mixture in a sealed environment for reaction to obtain Te^2-a precursor aqueous solution;

Step 2: adding 0.001/7 multiplied by 0.965-0.002/7 multiplied by 0.965mol of ammonium paramolybdate and 0.000005-0.00001 mol of copper acetate into 10ml of solvent for dissolving, and then adding 0.0025-0.005 mol of citric acid to obtain a precursor solution of the molybdenum ion source;

and step 3: mixing Te^2-placing the precursor aqueous solution and the molybdenum ion source precursor solution into a reaction kettle, keeping the solution at room temperature, and then carrying out gradient temperature rise to 15 DEGCarrying out hydrothermal reaction at 5-165 ℃, cooling to room temperature, filtering, cleaning a filtered substance, and drying to obtain flaky semimetal MoTe₂Cu and flaky semi-metal MoTe₂:Cu/RGO。

Further, in the step 1, the weight ratio of the tellurium powder to the potassium borohydride is 1: 2.

Furthermore, the reaction time in the step 1 is 40-50 h.

Further, the solvent in step 2 is deionized water.

Further, the solvent in the step 2 is 1mg/ml graphene oxide aqueous solution.

Further, the time for keeping at room temperature in the step 3 is 10-12 hours.

Further, in the step 3, the temperature is raised to 45-55 ℃ and kept for 4-5 h, then raised to 95-105 ℃ and kept for 3-4 h, and then raised to 155-165 ℃ for hydrothermal reaction for 15-17 h.

Further, the heating rate of the gradient temperature rise in the step 3 is 10-40 ℃/min.

Further, deionized water and ethanol are adopted for cleaning in the step 3.

Further, the drying in the step 3 is carried out at the temperature of 50-60 ℃ for 12-14 h.

Compared with the prior art, the invention has the following beneficial technical effects:

the invention provides flaky semimetal MoTe₂Cu and flaky semi-metal MoTe₂In the preparation method of Cu/RGO, citric acid plays a role in dispersing and chelating in the preparation process, and hydrothermal reactions are respectively carried out at stepped hydrothermal temperatures, so that copper-doped flaky semi-metal ditelluride is directly generated, and a massive semiconductor ditelluride does not need to be synthesized firstly and then layered by applying various complex chemical and physical layering methods; the introduction of citric acid reduces the activation energy of a reaction system, the formation energy of the flaky semi-metal molybdenum ditelluride or flaky semi-metal molybdenum ditelluride/graphene oxide is low, and the copper-doped flaky semi-metal is successfully constructed at a lower temperatureStructure of molybdenum ditelluride

Furthermore, the solution is a graphene oxide aqueous solution, RGO generated in the reaction process serves as a template, copper-doped flaky semimetal molybdenum ditelluride generated by the reaction is compounded with RGO, and the introduction of graphene increases the conductivity of the semimetal molybdenum ditelluride and generates an interface effect so as to enhance the hydrogen evolution catalysis performance of the semimetal structure molybdenum ditelluride; in addition, Cu ion doping can also enhance the conductivity of the semimetal molybdenum ditelluride and enhance the hydrogen evolution catalytic performance of the semimetal molybdenum ditelluride.

Drawings

FIG. 1 shows the half-metals MoTe prepared in examples 1 and 2 of the present invention₂Cu and a semi-metal MoTe₂TEM image of Cu/RGO;

FIG. 2 shows the half-metals MoTe prepared in examples 1 and 2 of the present invention₂cu and a semi-metal MoTe₂XRD pattern of Cu/RGO;

FIG. 3 shows the half-metals MoTe prepared in examples 1 and 2 of the present invention₂Cu and a semi-metal MoTe₂Raman spectra of Cu/RGO;

FIG. 4 shows the half-metals MoTe prepared in examples 1 and 2 of the present invention₂Cu and a semi-metal MoTe₂infrared spectrum of Cu/RGO;

FIG. 5 shows the half-metals MoTe prepared in examples 1 and 2 of the present invention₂cu and a semi-metal MoTe₂Fluorescence spectra of Cu/RGO.

Detailed Description

Specific examples are given below.