CN104528812B - A kind of preparation method of flower-shaped PbS/Ni2P composite material - Google Patents

Abstract

A kind of flower-shaped PbS/Ni ₂the preparation method of P matrix material, first solvent-thermal method is used to prepare homogeneous flower-shaped lead sulfide, by flower-shaped lead sulfide, Nickel dichloride hexahydrate, cetyl trimethylammonium bromide and sodium lauryl sulphate mixed surfactant, yellow phosphorus by certain stoichiometric ratio, hydrothermal treatment consists, the product vacuum obtained is dry, prepares flower-shaped PbS/Ni ₂p matrix material, flower-shaped lead sulfide is that nickel phosphide provides effective three-dimensional space, and solve nickel phosphide nanoparticle and to reunite the technical problem causing catalytic performance lower, raw material of the present invention is easy to get, and preparation technology is simple.

Description

A kind of preparation method of flower-shaped PbS/Ni2P composite material

technical field

The invention relates to the technical field of composite material preparation, in particular to a method for preparing a flower-shaped PbS/Ni ₂ P composite material.

Background technique

Lead sulfide is a typical narrow bandgap semiconductor with a bandgap width of 0.41eV at room temperature. In the past few decades, lead sulfide has been widely used in photoluminescence, photoelectric conversion, nonlinear optics, etc. Due to the relatively large exciton Bohr radius (18nm), lead sulfide (PbS) can exhibit quantum size effects when the particle or grain size is relatively large. However, PbS is unstable, especially PbS nanoparticles have higher surface energy, poorer stability, and Pb ^{2+ is} toxic. In order to improve the stability of PbS and improve the photoelectric conversion efficiency of PbS, researchers have made many Exploration, such as modifying the PbS surface by polymers; improving the surface structure of PbS nanostructures by controlling the morphology; and recombination of two semiconductors to achieve the separation of photogenerated charges and holes, etc. Among numerous inorganic nanomaterials, studies have found that transition metal phosphides, especially nickel phosphide, are new catalysts with high activity, high stability and resistance to sulfur poisoning. After the two semiconductors are combined, because nickel phosphide has a higher conduction band energy level, the photogenerated electrons in the flower-like PbS/Ni ₂ P composite material are conducive to the migration to the nickel phosphide conduction band, which reduces the photogenerated electron-vacancy level. The recombination of hole pairs can achieve the effective separation of photogenerated electrons and improve the photoelectric performance of the material. In addition, compared with zero-dimensional and one-dimensional nanomaterials, nanomaterials with three-dimensional branched structures not only maintain the quantum effects of nanomaterials, but also have the continuity of charge transport in bulk materials. This excellent performance makes nanomaterials with multidimensional branched structures Materials in catalysis, photoelectric conversion, photoluminescence, etc. By compounding Ni ₂ P on the surface of the three-dimensional flower-like PbS material, by regulating the energy level structure, the electron transport is limited to a specific space, so as to isolate the electron-hole transport channel and reduce the charge recombination. At present, there are many reports on the composite materials of PbS assembled on other semiconductor materials, but there are few composite materials on the composite of semiconductor materials on PbS, and the flower-like PbS/Ni ₂ P composite materials and their preparation methods have not been reported.

Contents of the invention

In order to overcome the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a preparation method of flower-shaped PbS/Ni ₂ P composite material, which has easy-to-obtain raw materials, simple preparation process and good repeatability.

In order to achieve the above object, the technical scheme that the present invention takes is:

A preparation method of a flower-shaped PbS/Ni ₂ P composite material, comprising the following steps:

Step A, add ethylene glycol (EG) solution with a volume of 10-15mL to the first Erlenmeyer flask, add 1-2mmol lead acetate trihydrate and 1-2mL acetic acid to it, stir magnetically, and add 1-2mL after dissolution 2mmol of sublimated sulfur, ultrasonically dispersed until uniform; transfer the solution into a polytetrafluoroethylene lining, then seal the polytetrafluoroethylene lining into a stainless steel mold, start heating from room temperature and heat at 120-160°C under airtight conditions React for 16 to 24 hours, cool to room temperature naturally after the reaction, wash the product with distilled water and absolute ethanol, and dry it in vacuum at 60°C for 4 to 6 hours to obtain flower-shaped lead sulfide;

Step B, add 12-18mL distilled water to the second Erlenmeyer flask, add 0.2-0.6mmol flower-shaped lead sulfide obtained in step A, stir magnetically until uniformly dispersed, add 0-0.3mmol hexadecyltri Mix methylammonium bromide (CTAB) and 0-0.1mmol sodium dodecyl sulfate (SDS) as a surfactant, stir until dissolved, then add 0.2-0.6mmol nickel chloride hexahydrate; Transfer to the polytetrafluoroethylene lining, then add 0.2-0.6mmol of yellow phosphorus to the solution, then seal the polytetrafluoroethylene lining into a stainless steel mold, start heating from room temperature under airtight conditions and heat it at 160-200 The reaction was heated at ℃ for 14-20 hours. After the reaction, it was naturally cooled to room temperature. The product was washed with distilled water, absolute ethanol and benzene, and dried in vacuum at 60 ℃ for 4-6 hours to obtain a flower-shaped PbS/Ni ₂ P composite material.

The polytetrafluoroethylene linings are all 20mL, and the filling degree is 60%-80%.

The present invention has the following beneficial effects:

1. Lead sulfide with specific morphology and structure provides a three-dimensional space for the effective compounding of nickel phosphide nanoparticles on it, which solves the technical problem of low catalytic performance caused by the agglomeration of nickel phosphide nanoparticles, and effectively prevents The agglomeration of nickel phosphide nanoparticles increases the effective contact area with the catalytic substrate and improves the catalytic performance.

2. The photogenerated electrons in the flower-like PbS/Ni ₂ P composite material are conducive to the migration to the nickel phosphide conduction band, reducing the recombination of photogenerated electron-hole pairs, so as to achieve the effective separation of photogenerated electrons and improve the photoelectric performance of the material.

3. The invention has low cost, easy-to-obtain raw materials, simple preparation process and good repeatability, and has potential application value in photocatalysis, photoelectric conversion and other fields.

Description of drawings

Figure 1 is the XRD pattern of the flower-like PbS/Ni ₂ P composite material obtained in Example 1 of the present invention.

Figure 2-a is the SEM image of the flower-shaped lead sulfide prepared in Example 1 of the present invention; Figure 2-b is the SEM image of the PbS/Ni ₂ P composite material prepared in Example 1 of the present invention.

Fig. 3 is an SEM image of the PbS/Ni ₂ P composite material prepared in Example 4 of the present invention.

detailed description

The present invention will be described in detail below in conjunction with the embodiments.

Example 1

A preparation method of a flower-shaped PbS/Ni ₂ P composite material, comprising the following steps:

Step A, add ethylene glycol (EG) solution with a volume of 14mL to the first Erlenmeyer flask, add 1mmol lead acetate trihydrate and 1.2mL acetic acid to it, stir magnetically, add 1.5mmol sublimated sulfur after dissolution, and ultrasonically disperse until uniform; transfer the solution into a polytetrafluoroethylene lining, then seal the polytetrafluoroethylene lining into a stainless steel mold, start heating from room temperature under airtight conditions and heat the reaction at 140 ° C for 24 hours, and naturally cool to At room temperature, the product was washed with distilled water and absolute ethanol, and dried in vacuum at 60°C for 4-6 hours to obtain flower-shaped lead sulfide;

Step B, add 16mL distilled water in the second Erlenmeyer flask, add 0.5mmol flower-shaped lead sulfide obtained in step A therein, magnetically stir until uniformly dispersed, add 0.3mmol cetyltrimethylammonium bromide ( CTAB) and 0.1mmol sodium dodecyl sulfate (SDS) mixed surfactant, after stirring until dissolved, add 0.25mmol nickel chloride hexahydrate; after the dissolution is complete, transfer the solution into the polytetrafluoroethylene lining, Then add 0.3mmol of yellow phosphorus to the solution, then seal the polytetrafluoroethylene liner into a stainless steel mold, start heating from room temperature under airtight conditions and heat the reaction at 180°C for 16h, and naturally cool to room temperature after the reaction. Wash with distilled water, absolute ethanol, and benzene, and dry in vacuum at 60°C for 4-6 hours to obtain a flower-like PbS/Ni ₂ P composite material.

The XRD patterns and SEM pictures of the flower-like PbS/Ni ₂ P composite material prepared in Example 1 are shown in Fig. 1 and Fig. 2-a, Fig. 2-b, wherein the diameter of the nickel phosphide nanoparticles is about 30nm.

Example 2

Change the amount of cetyltrimethylammonium bromide (CTAB) to 0.0mmol in Step B in Example 1, and keep other conditions unchanged. The surface of the flower-shaped lead sulfide in the product is smooth, and nickel phosphide is basically not compounded on its surface. .

Example 3

Change the amount of sodium dodecyl sulfate (SDS) in Step B in Example 1 to 0.0mmol, and other conditions remain unchanged. In the product, flower-shaped lead sulfide and nickel phosphide are mixed, and a small amount of phosphide is compounded on the surface of flower-shaped lead sulfide. Nickel nanoparticles.

Example 4

Cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) consumption are all changed into 0.1mmol in step B in the embodiment 1, other conditions are constant, the surface of flower-shaped lead sulfide in the product The nickel phosphide nanoparticles with severe agglomeration were attached, and the particle size of the prepared nickel phosphide nanoparticles was larger than that of Example 1 (d≈100nm), as shown in FIG. 3 .

Example 5

The temperature in Step B in Example 1 was adjusted to 160°C, and the other conditions remained unchanged. The morphology of the product was similar to that of Example 1, but XRD showed that the nickel phosphide phase was impure and contained Ni ₁₂ P ₅ miscellaneous peaks.

The specific embodiments of the present invention have been described in detail above, and product phenomena of different embodiments have been described, but they are only examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, equivalent changes and modifications made without departing from the spirit and scope of the present invention shall fall within the scope of the present invention.

Claims (3)

1. a flower-shaped PbS/Ni ₂the preparation method of P matrix material, is characterized in that, comprises the following steps:

Steps A, adds ethylene glycol (EG) solution of volume 10 ~ 15mL in the first Erlenmeyer flask, and add three acetate hydrate lead and 1 ~ 2mL acetic acid of 1 ~ 2mmol wherein, magnetic agitation, adds 1 ~ 2mmol sublimed sulphur after to be dissolved, ultrasonic disperse is to even; Solution is proceeded in polytetrafluoroethyllining lining, then polytetrafluoroethyllining lining is sealed in stainless steel mould, in confined conditions by room temperature heating and at 120 ~ 160 DEG C of reacting by heating 16 ~ 24h, reaction end naturally cools to room temperature, product is through distilled water, absolute ethanol washing, and vacuum 60 DEG C of drying 4 ~ 6h obtain flower-shaped lead sulfide;

Step B, 12 ~ 18mL distilled water is added in the second Erlenmeyer flask, add the flower-shaped lead sulfide that 0.2 ~ 0.6mmol steps A obtains wherein, magnetic agitation is to dispersed, add 0.3mmol cetyl trimethylammonium bromide (CTAB) and 0 ~ 0.1mmol sodium lauryl sulphate (SDS) mixed surfactant wherein, after being stirred to dissolving, add 0.2 ~ 0.6mmol Nickel dichloride hexahydrate; To be dissolved completely after, solution is proceeded in polytetrafluoroethyllining lining, the yellow phosphorus of 0.2 ~ 0.6mmol is added again in solution, then polytetrafluoroethyllining lining is sealed in stainless steel mould, in confined conditions by room temperature heating and at 160 ~ 200 DEG C of reacting by heating 14 ~ 20h, reaction end naturally cools to room temperature, and product is through distilled water, dehydrated alcohol, benzene washing, and vacuum 60 DEG C of drying 4 ~ 6h obtain flower-shaped PbS/Ni ₂p matrix material.

2. the flower-shaped PbS/Ni of one according to claim 1 ₂the preparation method of P matrix material, is characterized in that: described polytetrafluoroethyllining lining is 20mL, and compactedness is 60% ~ 80%.

3. the flower-shaped PbS/Ni of one according to claim 1 ₂the preparation method of P matrix material, is characterized in that, comprises the following steps:

Steps A, adds ethylene glycol (EG) solution of volume 14mL in the first Erlenmeyer flask, and add three acetate hydrate lead and the 1.2mL acetic acid of 1mmol wherein, magnetic agitation, adds 1.5mmol sublimed sulphur after to be dissolved, ultrasonic disperse is to even; Solution is proceeded in polytetrafluoroethyllining lining, then polytetrafluoroethyllining lining is sealed in stainless steel mould, in confined conditions by room temperature heating and at 140 DEG C of reacting by heating 24h, reaction end naturally cools to room temperature, product is through distilled water, absolute ethanol washing, and vacuum 60 DEG C of drying 4 ~ 6h obtain flower-shaped lead sulfide;

Step B, 16mL distilled water is added in the second Erlenmeyer flask, add the flower-shaped lead sulfide that 0.5mmol steps A obtains wherein, magnetic agitation is to dispersed, add 0.3mmol cetyl trimethylammonium bromide (CTAB) and 0.1mmol sodium lauryl sulphate (SDS) mixed surfactant wherein, after being stirred to dissolving, add 0.25mmol Nickel dichloride hexahydrate; To be dissolved completely after, solution is proceeded in polytetrafluoroethyllining lining, the yellow phosphorus of 0.3mmol is added again in solution, then polytetrafluoroethyllining lining is sealed in stainless steel mould, in confined conditions by room temperature heating and at 180 DEG C of reacting by heating 16h, reaction end naturally cools to room temperature, and product is through distilled water, dehydrated alcohol, benzene washing, and vacuum 60 DEG C of drying 4 ~ 6h obtain flower-shaped PbS/Ni ₂p matrix material.