阅读说明：本技术 一种碘掺杂溴氧铋光催化剂在固氮方面的新应用 (Novel application of iodine-doped bismuth oxybromide photocatalyst in aspect of nitrogen fixation ) 是由 滕飞 袁晨 刘再伦 杨小嫚 滕怡然 顾文浩 刘喆 于 2020-07-16 设计创作，主要内容包括：本发明公开了一种碘掺杂溴氧铋光催化剂在固氮方面的新应用,该碘掺杂溴氧铋光催化剂呈微米球状,其化学式为Bi<Sub>4</Sub>O<Sub>5</Sub>Br<Sub>x</Sub>I<Sub>2-X</Sub>。本发明Bi<Sub>4</Sub>O<Sub>5</Sub>Br<Sub>x</Sub>I<Sub>2-X</Sub>光催化剂材料,其制作方法简易、环保、成本低廉,产品纯净。本发明制备得到的光催化剂在可见光下具有良好的固氮应用前景。(The invention discloses a new application of an iodine-doped bismuth oxybromide photocatalyst in nitrogen fixation, wherein the iodine-doped bismuth oxybromide photocatalyst is in a micron sphere shape and has a chemical formula of Bi 4 O 5 Br x I 2‑X . Bi of the invention 4 O 5 Br x I 2‑X The photocatalyst material has the advantages of simple preparation method, environmental protection, low cost and pure product. The photocatalyst prepared by the invention has good nitrogen fixation application prospect under visible light.)

1. The iodine-doped bismuth oxybromide photocatalyst is characterized in that the iodine-doped bismuth oxybromide photocatalyst is in a micron sphere shape, the average diameter of the iodine-doped bismuth oxybromide photocatalyst is 2.0-9.0 mu m, and the chemical formula of the iodine-doped bismuth oxybromide photocatalyst is Bi₄O₅Br_xI_2-XWherein the value range of x is 0-2.

2. The iodine-doped bismuth oxybromide photocatalyst as claimed in claim 1, wherein the average diameter of the iodine-doped bismuth oxybromide photocatalyst is 3.0-3.5 μm, and the chemical formula is Bi₄O₅BrI。

3. The method for preparing the iodine doped bismuth oxybromide photocatalyst of claim 1, which is characterized in that the method for preparing the iodine doped bismuth oxybromide photocatalyst comprises the following steps:

(1) adding 1.5mmol of bismuth nitrate hexahydrate into 5mL of ethylene glycol, and uniformly stirring;

(2) adding 0-1 mmol of potassium iodide and 0-1 mmol of potassium bromide into 15mL of ethylene glycol, and uniformly stirring; the total mole number of the potassium iodide and the potassium bromide is 1 mmol;

(3) mixing the solutions obtained in the step (1) and the step (2), uniformly stirring, adding the mixture into a polytetrafluoroethylene lining, and carrying out hydrothermal reaction at a constant temperature of 180 ℃ for 16 hours; centrifuging, washing and drying to obtain the product Bi₄O₅Br_xI_2-X。

4. The new application of the iodine doped bismuth oxybromide photocatalyst in the aspect of photocatalysis and nitrogen fixation of the iodine doped bismuth oxybromide photocatalyst in claim 1.

5. The new application of the iodine doped bismuth oxybromide photocatalyst in the aspect of photocatalysis and nitrogen fixation as claimed in claim 3 is characterized in that the photocatalysis adopts visible light.

Technical Field

The invention relates to a new application of an iodine-doped bismuth oxybromide photocatalyst in nitrogen fixation.

Background

The solar photocatalytic nitrogen fixation is an effective method for converting nitrogen into ammonia under mild conditions, and the core of the method is to develop a high-efficiency catalytic material to improve the adsorption and activation capacity of nitrogen. Shoxin and the like adopt a microwave method to prepare iodine-doped nano Bi4O5Br2, and the degradation performance of the iodine-doped nano Bi4O5Br2 on butylparaben and bisphenol A is reported, but the microwave method needs a special device and is not beneficial to large-scale production (CN: 107308961A). FIG. shun et al reports the degradation performance of Bi/Bi4O5Br2/BiOI ternary bismuth-based composite photocatalyst (CN: 107790157A), which is not the iodine doping range. Zhao Lu and the like utilize a cobalt oxyhydroxide bifunctional catalyst to carry out high-efficiency nitrogen fixation reaction application (CN: 110479277A); bi₄O₅X₂The (Cl, Br, I) semiconductor photocatalytic material has good photocatalytic activity due to the unique layered structure and electronic properties. However, the nitrogen fixation yield of the semiconductor photocatalytic material cannot meet the demand. Weiqin and the like change the performance of pure bismuth oxybromide based on gold functionalized titanium doped bismuth oxybromide microspheres (CN: 108982481A). But is too costly to be a good choice. Therefore, how to increase the active sites and improve the adsorption and activation capability of the semiconductor photocatalytic material on nitrogen becomes a key while maintaining the good photocatalytic activity of the semiconductor photocatalytic material.

Disclosure of Invention

The invention aims to solve the defects in the prior art and provide a photocatalyst which is low in cost and has high-efficiency nitrogen fixation performance.

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

an iodine-doped bismuth oxybromide photocatalyst which is in a uniform micron sphere shape, has an average diameter of 2.0-9.0 mu m and has a chemical formula of Bi₄O₅Br_xI_2-XWherein the value range of x is 0-2. Wherein, the value of x is preferably 1, namely the chemical formula of the iodine doped bismuth oxybromide photocatalyst is Bi₄O₅BrI, mean diameter 3.0～3.5μm。

The invention also provides a preparation method of the iodine-doped bismuth oxybromide photocatalyst, which comprises the following steps:

(1) adding 1.5mmol of bismuth nitrate hexahydrate into 5mL of ethylene glycol, and uniformly stirring;

(2) adding 0-1 mmol of potassium bromide and 0-1 mmol of potassium iodide (the sum of the total molar amount of the potassium bromide and the potassium iodide is 1 mmol) into 15mL of ethylene glycol, and uniformly stirring;

(3) mixing the solutions obtained in the step (1) and the step (2), uniformly stirring, adding the mixture into a polytetrafluoroethylene lining, and carrying out hydrothermal reaction at a constant temperature of 180 ℃ for 16 hours; centrifuging, washing and drying to obtain the product Bi₄O₅Br_xI_2-X。

The invention also provides a new application of the iodine-doped bismuth oxybromide photocatalyst in the aspect of photocatalytic nitrogen fixation.

Wherein the photocatalysis is visible light.

Compared with the prior art, the invention has the following advantages:

bi of the invention₄O₅Br_xI_2-XThe photocatalyst material has the advantages of simple preparation method, environmental protection, low cost, pure product and good nitrogen fixation performance under visible light. The photocatalyst prepared by the invention has good application prospect.

Drawings

FIG. 1 shows Bi prepared in example one₄O₅Br_xI_2-XAn X-ray diffraction (XRD) pattern of the photocatalyst;

FIG. 2 shows Bi prepared in example one₄O₅Br_xI_2-XA Scanning Electron Microscope (SEM) image of the photocatalyst;

as can be seen from FIG. 2, Bi prepared in example one₄O₅Br_xI_2-XThe photocatalyst is uniform microspheres.

FIG. 3 shows Bi prepared in test example one₄O₅Br_xI_2-xA comparison graph of the nitrogen fixation performance of the photocatalyst; in FIG. 3, the ordinate represents nitreThe rate of nitrogen generation.

As can be seen from FIG. 3, Bi₄O₅Br_xI_2-XThe photocatalyst has the performance of generating nitrate nitrogen under visible light, and Bi₄O₅The BrI nitrogen fixation performance is optimal.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.