阅读说明：本技术 一种光催化降解罗丹明B的[CuCN]配位聚合物及其制备方法和应用 ([ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B, and preparation method and application thereof ) 是由 赵志凤 李柏茹 陈见围 林双燕 苏占华 于 2020-08-12 设计创作，主要内容包括：一种光催化降解罗丹明B的[CuCN]配位聚合物及其制备方法和应用,涉及[CuCN]配位聚合物及其制备方法和应用。解决现有光催化降解有机污染物的催化效率和稳定性不佳的问题。化学式为{[Cu(CN)<Sub>2</Sub>][Cu<Sub>2</Sub>(CN)(py)]}<Sub>n</Sub>,py为吡嗪,单斜晶系,空间群为C2/c,晶胞参数为<Image he="53" wi="700" file="DDA0002629491800000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>α＝90°,β＝103.1016(6)°,γ＝90°,Z＝2。方法：将K<Sub>4</Sub>Fe(CN)<Sub>6</Sub>·3H<Sub>2</Sub>O加入到溶剂中,得到反应体系,向反应体系中加入CuCl<Sub>2</Sub>·2H<Sub>2</Sub>O、KF及吡嗪,调节pH,最后晶化。应用：用于光催化降解罗丹明B。([ CuCN ] for photocatalytic degradation of rhodamine B]A coordination polymer, a preparation method and application thereof, relating to [ CuCN ]]Coordination polymer and preparation method and application thereof. The problem of current photocatalytic degradation organic pollutant's catalytic efficiency and stability are not good is solved. Has a chemical formula of { [ Cu (CN) 2 ][Cu 2 (CN)(py)]} n Py is pyrazine, monoclinic, space group is C2/C, cell parameters are α is 90 °, β is 103.1016(6 °), γ is 90 °, and Z is 2. The method comprises the following steps: will K 4 Fe(CN) 6 ·3H 2 Adding O into solvent to obtain reaction system, adding CuCl into the reaction system 2 ·2H 2 O, KF and a pyrazine, in the form of a liquid,adjusting pH, and crystallizing. The application comprises the following steps: the method is used for photocatalytic degradation of rhodamine B.)

1. LightCatalytic degradation of rhodamine B [ CuCN]The coordination polymer is characterized in that [ CuCN ] for degrading rhodamine B through photocatalysis]The chemical formula of the coordination polymer is { [ Cu (CN)₂][Cu₂(CN)(py)]}_nWherein py is pyrazine, crystal system is monoclinic system, space group is C2/C, and unit cell parameter is

2. The method for preparing the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 1, wherein the method for preparing the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B is carried out according to the following steps:

firstly, under the conditions of room temperature and stirring speed of 60-100 r/min, adding K₄Fe(CN)₆·3H₂Adding O into the solvent, and stirring to K₄Fe(CN)₆·3H₂Dissolving O, continuously stirring for 40-60 min to obtain a reaction system, and adding CuCl into the reaction system at room temperature and at a stirring speed of 60-100 rpm₂·2H₂Stirring and dissolving O, adding KF, stirring and dissolving, adding pyrazine, continuously stirring until the mixture is uniformly mixed, and finally adjusting the pH value to 5.2-5.5 to obtain a reaction solution;

said K₄Fe(CN)₆·3H₂O and CuCl₂·2H₂The molar ratio of O is 1 (1.0-1.1);

said K₄Fe(CN)₆·3H₂The molar ratio of O to KF is 1 (2.3-2.5);

said K₄Fe(CN)₆·3H₂The molar ratio of O to pyrazine is 1 (2.0-2.2);

said K₄Fe(CN)₆·3H₂The molar ratio of O to the solvent is 1 (1350-1400);

secondly, adding the reaction solution into a polytetrafluoroethylene reaction kettle according to the filling degree of the polytetrafluoroethylene reaction kettle volume of 60-75%, then crystallizing for 116-120 h at the temperature of 150-160 ℃, naturally cooling to room temperature to obtain light yellow blocky crystals, repeatedly washing the crystals with distilled water, and drying to obtain the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B;

the [ CuCN ] for degrading rhodamine B through photocatalysis]The chemical formula of the coordination polymer is { [ Cu (CN)₂][Cu₂(CN)(py)]}_nWherein py is pyrazine, crystal system is monoclinic system, space group is C2/C, and unit cell parameter is

3. The method for preparing [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 2, wherein the solvent in the first step is distilled water.

4. The method for preparing [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 2, wherein the pH value adjusted to 5.2-5.5 in the step one is adjusted by using HCl with a concentration of 0.1-0.2 mol/L.

5. [ CuCN ] for photocatalytic degradation of rhodamine B according to claim 2]The preparation method of coordination polymer is characterized in that in the step one, K is added under the conditions of room temperature and stirring speed of 80-100 r/m₄Fe(CN)₆·3H₂Adding O into the solvent, and stirring to K₄Fe(CN)₆·3H₂Dissolving O, continuously stirring for 40-50 min to obtain a reaction system, and adding CuCl into the reaction system at room temperature and at a stirring speed of 80-100 rpm₂·2H₂And O, stirring and dissolving, adding KF, stirring and dissolving, adding pyrazine, continuously stirring until the pyrazine is uniformly mixed, and finally adjusting the pH value to 5.2-5.5 to obtain a reaction solution.

6. The method of claim 2The [ CuCN ] of the photocatalytic degradation of rhodamine B]A process for preparing a coordination polymer, characterized in that K is as defined in step one₄Fe(CN)₆·3H₂O and CuCl₂·2H₂The molar ratio of O is 1: 1; k in step one₄Fe(CN)₆·3H₂The molar ratio of O to KF is 1: 2.5; k in step one₄Fe(CN)₆·3H₂The molar ratio of O to pyrazine is 1:2.

7. The method for preparing the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 2, wherein the reaction solution is added into a polytetrafluoroethylene reaction kettle according to the filling degree of the polytetrafluoroethylene reaction kettle volume of 70-75% in the second step.

8. The method for preparing the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 2, wherein the crystallization is performed for 120 hours at a temperature of 160 ℃ in the second step.

9. The application of the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 1, wherein the [ CuCN ] coordination polymer is used for photocatalytic degradation of rhodamine B.

10. The application of the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B according to claim 9, wherein the photocatalytic degradation of rhodamine B is performed according to the following steps:

adding [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B into 0.5-0.75 mass percent of rhodamine B solution to obtain mixed solution, placing the mixed solution in a dark room, and performing photocatalytic degradation for 120-160 min under the conditions that the stirring speed is 60-100 r/min, the light source intensity of an ultraviolet lamp is 100-125W, and the ultraviolet lamp is placed 10-15 cm above the mixed solution;

the [ CuCN ] coordination polymer for degrading rhodamine B through photocatalysis has the mass and the volume ratio of 0.5-0.75% of rhodamine B solution of 1mg (2.0-2.2) mL.

Technical Field

The invention relates to a [ CuCN ] coordination polymer and a preparation method and application thereof.

Background

With the increasing emphasis on the environment, the research on photocatalytic degradation of organic pollutants is also more and more emphasized by people. The catalyst is a main factor influencing the effect of photocatalytic degradation of organic pollutants, the MOF material shows excellent performance in the process due to the structural characteristics of the MOF material, but in the process of photocatalytic degradation of organic pollutants, the activity of the catalyst is reduced along with the increase of the catalytic reaction times, even the catalyst is poisoned, so that the catalytic efficiency is greatly reduced, the stability is poor, and the catalyst is obviously reduced after about 10 times of circulation.

Disclosure of Invention

The invention aims to solve the problem of poor catalytic efficiency and stability of the existing photocatalytic degradation of organic pollutants, and provides a [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B, and a preparation method and application thereof.

[ CuCN ] for photocatalytic degradation of rhodamine B]The chemical formula of the coordination polymer is { [ Cu (CN)₂][Cu₂(CN)(py)]}_nWherein py is pyrazine, crystal system is monoclinic system, space group is C2/C, and unit cell parameter isα＝90°，β＝103.1016(6)°，γ＝90°，Z＝2。

The preparation method of the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B comprises the following steps:

firstly, under the conditions of room temperature and stirring speed of 60-100 r/min, adding K₄Fe(CN)₆·3H₂Adding O into the solvent, and stirring to K₄Fe(CN)₆·3H₂Dissolving O, continuously stirring for 40-60 min to obtain a reaction system, and adding CuCl into the reaction system at room temperature and at a stirring speed of 60-100 rpm₂·2H₂Dissolving O with stirring, adding KF, dissolving with stirring, and addingContinuously stirring pyrazine until the pyrazine is uniformly mixed, and finally adjusting the pH value to 5.2-5.5 to obtain a reaction solution;

said K₄Fe(CN)₆·3H₂O and CuCl₂·2H₂The molar ratio of O is 1 (1.0-1.1);

said K₄Fe(CN)₆·3H₂The molar ratio of O to KF is 1 (2.3-2.5);

said K₄Fe(CN)₆·3H₂The molar ratio of O to pyrazine is 1 (2.0-2.2);

said K₄Fe(CN)₆·3H₂The molar ratio of O to the solvent is 1 (1350-1400);

secondly, adding the reaction solution into a polytetrafluoroethylene reaction kettle according to the filling degree of the polytetrafluoroethylene reaction kettle volume of 60-75%, then crystallizing for 116-120 h at the temperature of 150-160 ℃, naturally cooling to room temperature to obtain light yellow blocky crystals, repeatedly washing the crystals with distilled water, and drying to obtain the [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B;

the [ CuCN ] for degrading rhodamine B through photocatalysis]The chemical formula of the coordination polymer is { [ Cu (CN)₂][Cu₂(CN)(py)]}_nWherein py is pyrazine, crystal system is monoclinic system, space group is C2/C, and unit cell parameter isα＝90°，β＝103.1016(6)°，γ＝90°，Z＝2。

An application of [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B is disclosed, which is used for photocatalytic degradation of rhodamine B.

The invention has the beneficial effects that: the novel [ CuCN ] base coordination polymer is prepared by a hydrothermal one-step method, the quality and yield (calculated by copper can reach 82%) of a product are greatly improved compared with those of a common aqueous solution method, the structure of the coordination polymer is determined by single crystal structure analysis, specifically, metal Cu in the coordination polymer is respectively connected with two cyanogen bridges and a ligand in a three-coordination mode so as to form a one-dimensional chain structure, an organic ligand and the two metal Cu act to form a two-dimensional network structure, and metal and the two cyanogen bridges are connected in a hydrogen bond action to penetrate through a two-dimensional pore channel so as to form a three-dimensional space structure, so that the novel [ CuCN ] base coordination polymer is provided.

Because the [ CuCN ] coordination polymer structurally forms a hole structure supported by covalent bonds, the covalent bonding of a ligand and metal increases the bonding strength between atoms, thereby enhancing the stability of the whole structure, and the [ CuCN ] coordination polymer for degrading rhodamine B by photocatalysis prepared by the invention has better photocatalytic activity on RhB. After the [ CuCN ] coordination polymer for degrading rhodamine B through photocatalysis is used for 140min for photocatalysis on RhB, the photocatalytic degradation rate can reach 95.80%, the [ CuCN ] coordination polymer catalyst for degrading rhodamine B can be recovered after being dried at 60-80 ℃, the photocatalytic degradation rate is kept at 93.2% -95.8% in the circulation process of 50 times, the catalytic performance is not changed, and the photocatalytic degradation rate is kept at 91.6% -93.0% in the circulation process of more than 50 times and 100 times and is slightly reduced.

The invention relates to a [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B, and a preparation method and application thereof.

Drawings

FIG. 1 is a schematic structural diagram of a [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B prepared in example one;

FIG. 2 is an infrared spectrum of [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B prepared in example one;

FIG. 3 is a graph showing the UV absorption curve of rhodamine B degraded by [ CuCN ] coordination polymer of photocatalytic rhodamine B prepared in the first example under UV irradiation;

FIG. 4 is a graph showing the degradation rate of degraded rhodamine B under UV irradiation, wherein 1 is no [ CuCN ] coordination polymer, and 2 is [ CuCN ] coordination polymer added with the rhodamine B photocatalytic degradation prepared in the first example;

FIG. 5 is an XRD spectrum before and after catalysis of [ CuCN ] coordination polymer for photocatalytic degradation of rhodamine B prepared in example one, wherein 1 is a curve before photocatalytic degradation of rhodamine B by [ CuCN ] coordination polymer, and 2 is a curve after photocatalytic degradation of rhodamine B for 20 times by [ CuCN ] coordination polymer.

Detailed Description