A hydroxyphenanthroline binuclear cobalt complex and its preparation method and application
By preparing a hydroxyphenotype binuclear cobalt complex as a catalyst, the problem of high catalyst cost in the photocatalytic reduction of carbon dioxide was solved, achieving efficient conversion of carbon dioxide into ethylene, reducing manufacturing costs and maintaining catalyst stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- YUNNAN NORMAL UNIV
- Filing Date
- 2023-11-23
- Publication Date
- 2026-06-02
AI Technical Summary
In existing technologies, the manufacturing cost of catalysts in the photocatalytic reduction of carbon dioxide is high and difficult to reduce effectively.
Using a hydroxyphenanthroline binuclear cobalt complex as a catalyst, a solid crystalline coordination compound is formed by a solvothermal reaction of 2,9-dichloro-1,10-phenanthroline and cobalt chloride hexahydrate in an ethanol solvent, utilizing inexpensive cobalt salts as raw materials.
This reduces the cost of catalyst preparation, achieves efficient photocatalytic reduction of carbon dioxide to ethylene, avoids the use of expensive precious metal catalysts, and has good catalyst stability.
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Figure CN117843694B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of functional materials technology of metal coordination compounds, specifically to a hydroxyphenanthroline binuclear cobalt complex, its preparation method, and its application. Background Technology
[0002] Global warming is considered one of the major environmental problems humanity is currently grappling with. Carbon dioxide is the primary cause of global climate change because it is 64% more efficient than other greenhouse gases in the atmosphere. This chemically stable gas contributes to rising global temperatures by absorbing and emitting infrared radiation. Furthermore, the trend of global warming has revealed even more significant changes over the past 20 years. The consequences of the greenhouse effect are global and severe. To address these problems, extensive research has been conducted over the past few decades, applying various strategies to control carbon dioxide emissions or convert them into other products.
[0003] In recent years, solar energy has been considered one of the most successful and promising resources for solving current environmental problems and meeting humanity's growing energy demands due to its sustainability, abundance, and cleanliness. Photocatalytic systems are among the promising technologies for converting solar energy into chemical energy. In the photocatalytic reduction of carbon dioxide, not only can solar energy be directly converted into stable chemical energy, but the amount of carbon dioxide in the atmosphere can also be reduced. This helps mitigate the effects of global warming, as carbon dioxide is a major cause of global climate change. Therefore, photocatalytic reduction of carbon dioxide is considered one of the most effective ways to obtain clean and renewable energy because it has the following advantages: utilizing solar energy, it is an economically feasible process with minimal environmental impact, chemical energy storage, and reduction of carbon dioxide levels. However, reducing the manufacturing cost of the catalyst used in the photocatalytic reduction of carbon dioxide is a major technical challenge in this field. Summary of the Invention
[0004] The purpose of this invention is to provide a hydroxyphenanthrene binuclear cobalt complex, its preparation method and application, and to solve the technical problem that the manufacturing cost of catalysts used in the photocatalytic reduction of carbon dioxide cannot be reduced in the prior art.
[0005] This invention discloses a hydroxyphenoxyline binuclear cobalt coordination compound with the molecular formula C. 48 H 26 Cl2Co2N8O6 has the following structural formula:
[0006] .
[0007] Furthermore, the coordination compound is in the form of a solid crystal, which belongs to the monoclinic crystal system, space group P21 / c, and has the following cell parameters: a = 10.2079(5) Å, b = 13.4193(6) Å, c = 14.4737(9) Å, α = alpha = 90°, β = = 106.353(5)°, γ = 90°, V = 1902.44(18) Å3.
[0008] Furthermore, the coordination compound is prepared from 2,9-dichloro-1,10-phenanthroline, ethanol, and cobalt chloride hexahydrate CoCl2·6H2O.
[0009] A method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound includes the following steps:
[0010] S1. Dissolve 2,9-dichloro-1,10-phenanthroline and cobalt chloride hexahydrate in a solvent to obtain a mixed solution;
[0011] S2. The mixture obtained in step S1 is subjected to a solvothermal reaction. After the reaction is completed, it is cooled to room temperature to precipitate red elongated crystals.
[0012] S3. Wash the red elongated crystals obtained in step S2, and after drying, a single crystal sample of the complex is obtained.
[0013] Furthermore, the molar ratio of 2,9-dichloro-1,10-phenanthroline to cobalt chloride hexahydrate in step S1 is 2:1.
[0014] Furthermore, the solvent is ethanol.
[0015] Furthermore, the molar ratio of ethanol to cobalt chloride hexahydrate is 1:1.
[0016] Furthermore, in step S2, the mixture is placed in a reaction vessel, sealed, and then subjected to a solvothermal reaction.
[0017] Furthermore, the reaction temperature of the solvothermal reaction in step S2 is 130~160℃, and the reaction time is 24~72 hours, more preferably 24~48 hours.
[0018] Furthermore, the cooling rate in step S2 is 10°C / h.
[0019] Further, in step S3, the red elongated crystals obtained in step S3 are washed with ethanol.
[0020] The application of a hydroxyphenoxyline binuclear cobalt coordination compound as a photocatalyst, especially for the photocatalytic reduction of carbon dioxide.
[0021] Furthermore, the hydroxyphenoline binuclear cobalt complex serves as a photocatalyst for the reduction of carbon dioxide to ethylene.
[0022] Compared with the prior art, the beneficial effects of the present invention are:
[0023] 1. This invention utilizes the bidentate coordination characteristic of 2,9-dichloro-1,10-phenanthroline to achieve the purpose of forming a coordination compound with cobalt ions;
[0024] 2. The invention uses inexpensive cobalt salt as a raw material, which reduces the preparation cost of the catalyst;
[0025] 3. The catalyst selected in this invention can effectively reduce carbon dioxide to ethylene, avoiding the use of expensive noble metal coordination compounds as catalysts;
[0026] 4. The hydroxyphenoxyline binuclear cobalt coordination compound of the present invention exhibits good stability when used as a photocatalyst. Attached Figure Description
[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 This is a schematic diagram of the crystal structure unit of the hydroxyphenoxyline binuclear cobalt coordination compound of Example 1 of the present invention.
[0029] Figure 2 This is the NMR spectrum of the hydroxyphenanthroline binuclear cobalt complex of Example 1 of the present invention.
[0030] Figure 3 This is a gas chromatogram of the hydroxyphenanthroline binuclear cobalt complex of Example 1 of the present invention.
[0031] Figure 4 This is a cyclic voltammetry curve of the hydroxyphenanthroline binuclear cobalt complex in Example 1 of the present invention. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0033] Example 1
[0034] 23.8 mg (0.1 mmol) of cobalt chloride hexahydrate and 24.9 mg (0.1 mmol) of 2,9-dichloro-1,10-phenanthroline were dissolved in ethanol (2 mL). The mixture was sealed and subjected to a solvothermal reaction at 160 °C for 72 h. After the reaction was carried out, the mixture was cooled to room temperature at a rate of 10 °C per hour to obtain red elongated crystals. These crystals were washed with ethanol and dried in a vacuum drying oven to obtain a single crystal sample of the hydroxyphenanthroline binuclear cobalt complex.
[0035] Example 2
[0036] This embodiment, as a preferred embodiment of the present invention, describes a method for preparing a hydroxyphenoxylate binuclear cobalt coordination compound, comprising the following steps:
[0037] 23.9 mg (0.1 mmol) of cobalt chloride hexahydrate and 49.8 mg (0.2 mmol) of 2,9-dichloro-1,10-phenanthroline were dissolved in ethanol (2 mL). The resulting mixture was sealed and subjected to a solvothermal reaction at 160 °C for 72 h. After the reaction, the mixture was cooled to room temperature at a rate of 10 °C per hour to obtain red elongated crystals. These crystals were washed with ethanol and dried in a vacuum drying oven to obtain a single crystal sample of the hydroxyphenanthroline binuclear cobalt complex.
[0038] Example 3
[0039] This embodiment, as a preferred embodiment of the present invention, describes a method for preparing a hydroxyphenoxylate binuclear cobalt coordination compound, comprising the following steps:
[0040] 23.8 mg (0.1 mmol) of cobalt chloride hexahydrate and 49.8 mg (0.2 mmol) of 2,9-dichloro-1,10-phenanthroline were dissolved in ethanol (2 mL). The resulting mixture was sealed and subjected to a solvothermal reaction at 160 °C for 48 h. After the reaction, the mixture was cooled to room temperature at a rate of 10 °C per hour to obtain red elongated crystals. These crystals were washed with ethanol and dried in a vacuum drying oven to obtain a single crystal sample of the hydroxyphenanthroline binuclear cobalt complex.
[0041] Example 4
[0042] This embodiment, as a preferred embodiment of the present invention, describes a method for preparing a hydroxyphenoxylate binuclear cobalt coordination compound, comprising the following steps:
[0043] 23.8 mg (0.1 mmol) of cobalt chloride hexahydrate and 49.8 mg (0.2 mmol) of 2,9-dichloro-1,10-phenanthroline were dissolved in ethanol (2 mL), and the three solutions were mixed to obtain a mixed solution. The final mixture was sealed and subjected to a solvothermal reaction at 160 °C for 48 h. After the reaction was carried out, it was cooled to room temperature at a rate of 10 °C per hour to obtain red elongated crystals. These crystals were washed with ethanol and dried in a vacuum drying oven to obtain a single crystal sample of the hydroxyphenanthroline binuclear cobalt complex.
[0044] Example 5
[0045] This embodiment, as a preferred embodiment of the present invention, describes a method for preparing a hydroxyphenoxylate binuclear cobalt coordination compound, comprising the following steps:
[0046] 23.7 mg (0.1 mmol) of cobalt chloride hexahydrate and 49.8 mg (0.2 mmol) of 2,9-dichloro-1,10-phenanthroline were dissolved in ethanol (2 mL). The resulting mixture was sealed and subjected to a solvothermal reaction at 160 °C for 72 h. After the reaction, the mixture was cooled to room temperature at a rate of 10 °C per hour to obtain red elongated crystals. These crystals were washed with ethanol and dried in a vacuum drying oven to obtain a single crystal sample of the hydroxyphenanthroline binuclear cobalt complex.
[0047] Test method:
[0048] The hydroxyphenanthrene binuclear cobalt complex prepared in Example 1 was subjected to single-crystal diffraction testing on a Rigaku R-AXIS SPIDER diffractometer. The test results are as follows: Figure 1 As shown in the figure, this diagram demonstrates the novel structure of the synthesized hydroxyphenobarline binuclear cobalt complex.
[0049] The hydroxyphenanthrene binuclear cobalt complex prepared in Example 1 1 HNMR, 1 ¹H NMR (400 MHz, DMSO-d⁶): δ 11.24 (s, 1H)), 8.54 (d, J = 8 Hz, 2H), 8.31 (d, J = 8.0 Hz, 2H), 7.87 (d, J = 8 Hz 1H), 7.79 (d, J = 8.0 Hz, 1H). Results are as follows: Figure 2 .
[0050] The hydroxyphenoxyline binuclear cobalt complex prepared in Example 1 was used as a photocatalyst for the reduction of carbon dioxide. The gas phase test results of the product at GC-2014C are as follows: Figure 3 As shown.
[0051] The hydroxyphenoxyline binuclear cobalt complex prepared in Example 1 was subjected to cyclic voltammetry testing, as follows: Figure 4 As shown, two irreversible waves were observed, Epc = -0.54V (vs. Fc). + / Fc) and Epc=-0.034V, respectively corresponding to Co II / I and Co I / 0 The redox couple was observed. An irreversible peak, Epc = -0.034V, was also observed, likely due to slow ligand exchange or dissociation. Comparing the peak currents under CO2 and N2 conditions, the peak current under CO2 conditions was larger than that under N2 conditions, indicating that the hydroxyphenanthroline binuclear cobalt complex responded better in CO2 than in N2, and that CO2 interacted with the metal center of the catalyst.
[0052] As can be seen, the hydroxyphenanthrene dinuclear cobalt complex synthesized in this invention not only has a novel structure and good thermal stability, but also exhibits certain photocatalytic effects. It can be used as a catalyst in photocatalytic systems to convert carbon dioxide into ethylene. Moreover, this invention is simple to operate and has potential application value in photocatalysis.
[0053] The above are the embodiments listed in this example. However, this example is not limited to the optional embodiments described above. Those skilled in the art can arbitrarily combine the above methods to obtain other various embodiments. Anyone can derive other various forms of embodiments based on the inspiration of this example. The above specific embodiments should not be construed as limiting the scope of protection of this example. The scope of protection of this example should be determined by the claims, and the specification can be used to interpret the claims.
Claims
1. A hydroxyphenoxyline binuclear cobalt coordination compound, characterized in that: The molecular structural formula is C 48 H 26 Cl2Co2N8O6 has the following structural formula: 。 2. The hydroxyphenoxyline binuclear cobalt coordination compound according to claim 1, characterized in that: The coordination compound is in the form of a solid crystal, which belongs to the monoclinic crystal system, space group P21 / c, and has the following cell parameters: a = 10.2079(5) Å, b = 13.4193(6) Å, c = 14.4737(9) Å, α = alpha=90°, β = =106.353(5)°, γ = 90°, V =1902.44(18)Å3.
3. The hydroxyphenoxyline binuclear cobalt coordination compound according to claim 1, characterized in that: The coordination compound was prepared from 2,9-dichloro-1,10-phenanthroline, ethanol, and cobalt chloride hexahydrate CoCl2·6H2O.
4. A method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound according to any one of claims 1-3, characterized in that: S1. Dissolve 2,9-dichloro-1,10-phenanthroline and cobalt chloride hexahydrate in a solvent to obtain a mixed solution; S2. The mixture obtained in step S1 is subjected to a solvothermal reaction. After the reaction is completed, it is cooled to room temperature to precipitate red elongated crystals. S3. Wash the red elongated crystals obtained in step S2, and after drying, a single crystal sample of the complex is obtained.
5. The method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound according to claim 4, characterized in that: The molar ratio of 2,9-dichloro-1,10-phenanthroline to cobalt chloride hexahydrate in step S1 is 2:
1.
6. The method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound according to claim 4, characterized in that: In step S2, the mixture is placed in a reaction vessel, sealed, and then subjected to a solvothermal reaction.
7. The method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound according to claim 4, characterized in that: The reaction temperature of the solvothermal reaction in step S2 is 130~160℃, and the reaction time is 24~72 hours.
8. The method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound according to claim 7, characterized in that: The reaction time for the solvothermal reaction in step S2 is 24 to 48 hours.
9. The method for preparing a hydroxyphenoxyline binuclear cobalt coordination compound according to claim 4, characterized in that: The cooling rate in step S2 is 10℃ / h.
10. The application of a hydroxyphenoxylate binuclear cobalt coordination compound according to any one of claims 1-3 or a compound prepared by the method according to any one of claims 4-9, characterized in that: As a photocatalyst.
11. The application of the hydroxyphenoxyline binuclear cobalt coordination compound according to claim 10, characterized in that: It is applied to the photocatalytic reduction of carbon dioxide.