Novel hybrid cuprous iodide luminescent material as well as preparation method and fluorescence application thereof

Abstract

The invention provides a novel hybrid cuprous iodide luminescent material as well as a preparation method and fluorescence application thereof, and particularly relates to two luminescent materials which are both organic-inorganic hybrids coordinated by organic ligands and inorganic cuprous iodide clusters, Cu4I4 (C9H12N3) 2 is of a two-dimensional double-layer network structure, the optimal excitation wavelength is 367 nm, and the strongest emission peak is 602 nm; cu2I2 (C11H8N) is of a one-dimensional chain structure of a trapezoidal grid structure, the optimal excitation wavelength is 419 nm, and the strongest emission peak is 521 nm. The luminescent material is prepared through crystallization in a diffusion process. The luminescent material shows better fluorescence emission performance, is a novel fluorescent crystal material with potential application value, and can be used in the fields of solid-state illumination, light emitting diodes, laser, fluorescent powder and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of luminescent materials, relates to a novel hybrid cuprous iodide luminescent material and a preparation method and fluorescence application thereof, and specifically discloses at least two novel organic-inorganic hybrid cuprous iodide luminescent materials and a preparation method thereof. Background Art

[0002] Organic-inorganic hybrid cuprous iodide materials have occupied an important position in the field of luminescent material research in recent years and are often regarded as candidate materials for the next generation of lighting technology. In addition to luminescent properties, hybrid cuprous iodide also exhibits many additional properties, such as porosity, conductivity, catalysis, and so on. In addition, the high natural abundance, low toxicity, and low pollution of the copper element make hybrid cuprous iodide materials have low economic consumption and excellent environmental friendliness. This series of materials has unique luminescent properties, including outstanding luminescent properties, diversity of luminescent colors, optical tunability, and so on. In particular, thanks to the excellent coordination chemical properties of monovalent copper ions, it can coordinate with many atoms such as C, N, O, P, As, S, and Se. Therefore, Cu + It can form crystals of different configurations with a variety of ligands in different coordination modes, which leads to the system showing extremely rich structural diversity.

[0003] Since the first hybrid cuprous iodide material was discovered in the 1970s, thousands of such materials have been reported in the Cambridge Crystal Database Center. These thousands of crystalline materials can be summarized into three different structural types: (i) Inorganic cuprous iodide clusters and organic ligands are both electrically neutral and connected by coordination bonds; (ii) Negatively charged cuprous iodide clusters and positively charged organic ligands do not form coordination bonds, but form crystals through the action of electrostatic Coulomb forces; (iii) Negatively charged inorganic cuprous iodide clusters and positively charged organic ligands are connected by coordination bonds and ionic bonds. Among them, the zero-dimensional structure in the i-type structure mainly includes a variety of basic inorganic cluster configurations such as Cu2I2-Cu8I8, including Cu2I2 rhombic dimer, Cu4I4 cubane tetramer, Cu6I6 ladder-shaped hexamer, Cu7I7 windmill-shaped heptamer, Cu8I8 ladder-shaped octamer, and Cu8I8 dicubane octamer. + All of them are three-coordinated or four-coordinated, forming triangular or cubic coordination geometric configurations. Inorganic clusters can form higher-dimensional crystal structures through organic ligands. Type I configurations also include different types of one-dimensional chain-like and two-dimensional layered inorganic clusters.

[0004] The prior art discloses some hybrid cuprous iodide crystal materials. For example, CN114835747B discloses a binuclear cuprous iodide complex luminescent material and a preparation method thereof, as well as the application of the material to fluorescence sensing of pyridine; the luminescent material structural formula is (m-To l3 P)2CuI2Cu(m-Tol3P), wherein m-Tol3P is an electrically neutral phosphine ligand tri(m-methylphenyl)phosphine; it is prepared by a coordination reaction between CuI and a ligand. CN104893715B discloses a yellow-green phosphorescent Cu4I4-type cubane cluster core complex luminescent material and a preparation method thereof. The provided phosphorescent complex is obtained by complexing cuprous iodide with a P-containing ligand, and its molecular structure is Cu4I4(m-anisyl3P)4, wherein m-anisyl3P is an electrically neutral P-containing ligand tri(m-methoxyphenyl)phosphine. CN109311913A discloses a highly thermally and light-stable inorganic-organic hybrid phosphor compound, wherein a cuprous (I) halide module is coordinated with a multidentate organic ligand; semiconductors and light-emitting devices containing these materials, including light-emitting diodes, and methods for preparing these materials and devices are also disclosed.

[0005] However, it remains challenging to further expand the categories of novel hybrid cuprous iodide materials and provide new design strategies through a deep understanding of the architecture-properties of the corresponding materials. Summary of the invention

[0006] The present invention utilizes the advantages of rich structural diversity, excellent luminescent performance and stability of organic-inorganic hybrid cuprous iodide, selects 1-(4-pyridyl)piperazine with special structure to coordinate with Cu4I4 cluster, and 2-(4-bromophenyl)pyridine to coordinate with Cu2I2 cluster, and then obtains two new hybrid cuprous iodide materials. The prepared luminescent material shows good fluorescence emission performance, is a new type of fluorescent crystal material with potential application value, and can be used in the fields of solid-state lighting, light-emitting diodes, lasers and phosphors, especially for orange and green fluorescence output under the excitation of ultraviolet light source.

[0007] The present invention is achieved through the following technical solutions:

[0008] On the one hand, the present invention provides a novel hybrid cuprous iodide luminescent material, wherein the molecular structure of the luminescent material is Cu4I4(1-(4-pyridinyl)piperazine)2, and the chemical formula is Cu4I4(C9H 12 N3)2, 1-(4-pyridinyl)piperazine is 1-(4-pyridinyl)piperazine. Further, the luminescent material Cu4I4(1-(4-pyridinyl)piperazine)2 is a two-dimensional double-layer network structure.

[0009] Furthermore, the Cu4I4(1-(4-pyridinyl)piperazine)2 is a monoclinic crystal with a P2 / c space group and a unit cell parameter of α=90°,β=97.758(2)°,γ=90°,unit cell volume

[0010] Each minimum asymmetric unit of the luminescent material Cu4I4(1-(4-pyridinyl)piperazine)2 contains two crystallographically independent Cu + , two I - , a 1-(4-pyridyl)piperazine organic ligand. Four Cu + With four I - The cubic Cu4I4 clusters were formed, and each 1-(4-pyridyl)piperazine ligand was bonded to two Cu on two Cu4I4 clusters. + Coordination. Each Cu4I4 cluster is coordinated with four 1-(4-pyridyl)piperazines, which are arranged in an up-and-down staggered pattern, forming a two-dimensional double-layer network structure.

[0011] On the one hand, the present invention provides a novel hybrid cuprous iodide luminescent material, whose molecular structure is Cu2I2(2-(4-bromophenyl)pyridine)2, and whose chemical formula is Cu2I2(C 11 H8N), 2-(4-bromophenyl)pyridine is 2-(4-bromophenyl)pyridine. Further, the luminescent material Cu2I2(2-(4-bromophenyl)pyridine)2 is a one-dimensional chain structure.

[0012] Furthermore, the Cu2I2(2-(4-bromophenyl)pyridine)2 is a monoclinic crystal with a P21 / n space group and a unit cell parameter of α=90°,β=93.184(17)°,γ=90°,unit cell volume

[0013] The luminescent material Cu2I2(2-(4-bromophenyl)pyridine)2 contains two crystallographically independent Cu in each minimum asymmetric unit. + , two I - , a 2-(4-bromophenyl)pyridine organic ligand. Cu + with I - The ladder-like inorganic grid clusters were formed in a 1:1 ratio, with 2-(4-bromophenyl)pyridine ligand and a Cu + Coordinate to form a one-dimensional chain structure.

[0014] On the one hand, the present invention provides a method for preparing a novel hybrid cuprous iodide luminescent material, which is prepared by a layered method, wherein an organic ligand and an inorganic cuprous iodide powder are dissolved in two different solvents, and then a mixed solvent is added to act as an intermediate buffer layer, and the target product is obtained by slow diffusion.

[0015] On the one hand, the present invention provides a method for preparing a novel hybrid cuprous iodide luminescent material, comprising the following steps: placing a cuprous iodide solution as a bottom solution, an aqueous solution as a buffer layer solution, and an organic ligand solution as a top layer solution in a reaction container in sequence, sealing the container and allowing the container to react, and after the reaction is completed, taking out the crystals, washing them, and drying them to obtain the luminescent material.

[0016] Furthermore, the preparation process of the cuprous iodide solution is as follows: taking excess potassium iodide and dissolving it in deionized water, filtering to obtain a saturated potassium iodide aqueous solution, and dissolving cuprous iodide under ultrasound to obtain a cuprous iodide solution.

[0017] Furthermore, the preparation process of the aqueous solution is as follows: deionized water and an organic solvent are mixed.

[0018] Furthermore, the preparation process of the organic ligand solution is as follows: an organic ligand is dissolved in an organic solvent to obtain the organic ligand solution.

[0019] Furthermore, the present invention provides a method for preparing a novel hybrid cuprous iodide luminescent material, comprising the following steps:

[0020] S1: Take excess potassium iodide and dissolve it in deionized water, filter it to obtain a saturated potassium iodide aqueous solution, and dissolve cuprous iodide under ultrasound to obtain a cuprous iodide solution;

[0021] S2: Mix deionized water and an organic solvent to prepare an aqueous solution;

[0022] S3: dissolving an organic ligand in an organic solvent to prepare an organic ligand solution;

[0023] S4: Cuprous iodide solution as a bottom solution, aqueous solution as a buffer solution and organic ligand solution as a top solution are placed in a reaction container in sequence, sealed and allowed to react. After the reaction is completed, the crystals are taken out, and the luminescent material is obtained by washing and drying.

[0024] The preparation method of the invention is simple, and a product with high purity can be obtained by standing at normal temperature and pressure. The method is simple and the conditions are convenient, which is conducive to large-scale production and easy to promote on a large scale.

[0025] Furthermore, the molar ratio of the organic ligand to cuprous iodide is 1:1 to 3, preferably 1:1, 1:2, 1:3, etc.

[0026] Furthermore, the organic ligand is selected from at least one of 2-(4-bromophenyl)pyridine and 1-(4-pyridyl)piperazine.

[0027] Furthermore, each of the organic solvents is independently selected from at least one of i-PrOH, EtOH, MeOH, TFE, HFIP, DCM, hexane, THF, toluene or benzene.

[0028] Furthermore, in S2, the volume ratio of the deionized water to the organic solvent is 1:1.

[0029] Furthermore, the buffer layer solution is slowly dripped onto the surface of the bottom layer solution.

[0030] Furthermore, the top layer solution is slowly dripped onto the surface of the buffer layer solution.

[0031] On the one hand, the present invention provides a novel hybrid cuprous iodide luminescent material for use in preparing solid-state lighting materials (e.g., residential lighting), light-emitting devices (e.g., light-emitting diodes), security and anti-counterfeiting materials (e.g., tracing markers and anti-counterfeiting), lasers, and phosphors.

[0032] Beneficial effects:

[0033] The present invention utilizes the advantages of rich structural diversity, excellent luminescent performance and stability of organic-inorganic hybrid cuprous iodide, selects 1-(4-pyridyl)piperazine with a special structure, and coordinates with Cu4I4 clusters to obtain a novel hybrid cuprous iodide material Cu4I4(1-(4-pyridinyl)piperazine)2. The luminescent material is a two-dimensional double-layer mesh structure, with an optimal excitation wavelength of 367nm and a strongest emission peak at 602nm, showing good orange fluorescence emission performance. It also shows good fluorescence emission performance and is a novel fluorescent crystal material with potential application value, which can be used in the fields of solid-state lighting, light-emitting diodes, lasers, phosphors, etc., especially for orange fluorescence output under the excitation of ultraviolet light sources.

[0034] The present invention utilizes the advantages of rich structural diversity, excellent luminescent performance and stability of organic-inorganic hybrid cuprous iodide, selects 2-(4-bromophenyl)pyridine with a special structure, and coordinates with Cu2I2 clusters to obtain a novel hybrid cuprous iodide material Cu2I2(2-(4-bromophenyl)pyridine)2. The luminescent material Cu2I2(2-(4-bromophenyl)pyridine)2 is a one-dimensional chain structure with a ladder grid structure, with an optimal excitation wavelength of 419nm and a strongest emission peak at 521nm, showing good green fluorescence emission performance. It also shows good fluorescence emission performance and is a novel fluorescent crystal material with potential application value, which can be used in the fields of solid-state lighting, light-emitting diodes, lasers, phosphors, etc., especially for green fluorescence output under the excitation of ultraviolet light sources.

[0035] The luminescent material prepared by the present invention has a completely new crystal structure, that is, Cu4I4(1-(4-pyridinyl)piperazine)2 is a two-dimensional double-layer network structure, and Cu2I2(2-(4-bromophenyl)pyridine)2 is a one-dimensional chain structure of a ladder-shaped grid structure; in particular, the one-dimensional chain structure of the ladder-shaped inorganic grid structure is a completely new inorganic cuprous iodide skeleton structure, and does not belong to any type reported previously. It greatly broadens the hybrid cuprous iodide material system and expands the types of materials. The luminescent materials prepared by the present invention are all organic-inorganic hybrids coordinated by organic ligands and inorganic cuprous iodide clusters.

[0036] The preparation method of the present invention has the advantages of simple process, low raw material cost, mild reaction conditions, high product yield, high purity and large size of prepared crystals; the required instruments and equipment are simple and easy to operate; the required solvent consumption is small, cost is saved, and large-scale technology promotion is easy. The luminescent material can be used to manufacture luminescent devices, as well as in the fields of phosphors, security and anti-counterfeiting. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the crystal structure of the sample prepared in Example 1 of the present invention along the crystal axis a (hydrogen atoms omitted).

[0038] Figure 2 Schematic diagram of the crystal structure of the sample prepared in Example 1 of the present invention along the crystal axis c (hydrogen atoms omitted).

[0039] Figure 3 This is the excitation and emission spectra of the sample prepared in Example 1 of the present invention.

[0040] Figure 4 Schematic diagram of the crystal structure of the sample prepared in Example 2 of the present invention along the crystal axis a (hydrogen atoms omitted).

[0041] Figure 5 Schematic diagram of the crystal structure of the sample prepared in Example 2 of the present invention along the crystal axis b (hydrogen atoms omitted).

[0042] Figure 6 This is the excitation and emission spectra of the sample prepared in Example 2 of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments.

[0044] The experimental materials used in the examples of the present invention but not specifically described are all conventional experimental materials in the art and can be purchased through commercial channels.

[0045] Example 1

[0046] The chemical composition formula of this embodiment is Cu4I4(C9H 12 The preparation method of the hybrid cuprous iodide luminescent material of N3)2 is as follows:

[0047] First, an excess of potassium iodide powder is dissolved in a certain amount of deionized water solution under stirring, and then filtered to obtain a saturated potassium iodide aqueous solution. Then, the ingredients are prepared according to the stoichiometric ratio, and high-purity cuprous iodide and 1-(4-pyridyl)piperazine powder are weighed respectively, and deionized water, saturated potassium iodide aqueous solution and ethanol solution are measured.

[0048] 1 mmol of cuprous iodide powder was dissolved in 3 mL of saturated potassium iodide aqueous solution by ultrasonication and placed on the bottom of a glass test tube; 0.5 mL of deionized water and 0.5 mL of ethanol were evenly mixed and placed on the cuprous iodide solution; then 0.5 mmol of 1-(4-pyridyl)piperazine powder was dissolved in 3 mL of ethanol solution by stirring and placed on the mixed solution of deionized water and ethanol.

[0049] Finally, the test tube was sealed with a sealing film and allowed to stand at room temperature for one week to grow crystals. The resulting crystals were taken out of the mother liquor, washed with ethanol and dried to obtain Cu4I4(C9H 12 N3)2 crystals (yield 100%).

[0050] The Cu4I4(C9H 12 The crystal structure diagram of N3)2 is as follows Figure 1 and Figure 2 The excitation and emission spectra are shown in Figure 3As shown. The excitation wavelength range is 300-400nm, there is one excitation peak at 375nm, and the emission peak is at 602nm. This shows that the hybrid cuprous iodide luminescent material can emit orange light.

[0051] Table 1 The novel hybrid cuprous iodide crystal material Cu4I4(C9H 12 Crystallographic data of N3)2

[0052]

[0053]

[0054] Example 2

[0055] The chemical composition formula of this embodiment is Cu2I2(C 11 The preparation method of the hybrid cuprous iodide luminescent material of H8N) is as follows:

[0056] First, an excess of potassium iodide powder is dissolved in a certain amount of deionized water solution under stirring, and then filtered to obtain a saturated potassium iodide aqueous solution. Then, the ingredients are prepared according to the stoichiometric ratio, high-purity cuprous iodide and 2-(4-bromophenyl)pyridine powder are weighed respectively, and deionized water, saturated potassium iodide aqueous solution and ethanol solution are measured.

[0057] 1 mmol of cuprous iodide powder was dissolved in 3 mL of saturated potassium iodide aqueous solution by ultrasonication and placed at the bottom of a glass test tube; 0.5 mL of deionized water and 0.5 mL of ethanol were evenly mixed and placed on the cuprous iodide solution; then 0.5 mmol of 2-(4-bromophenyl)pyridine powder was dissolved in 3 mL of ethanol solution by stirring and placed on the mixed solution of deionized water and ethanol.

[0058] Finally, the test tube was sealed with a sealing film and allowed to stand at room temperature for one week to grow crystals. The resulting crystals were taken out of the mother liquor, washed with ethanol and dried to obtain Cu2I2(C 11 H8N) crystals. (yield 100%)

[0059] The Cu2I2(C 11 The structural diagram of H8N crystal is shown in Figure 4 and Figure 5 The excitation and emission spectra are shown in Figure 6 As shown. The excitation wavelength range is 300-460nm, with one excitation peak at 419nm and an emission peak at 521nm. This indicates that the hybrid cuprous iodide luminescent material can emit green light.

[0060] Table 2 The novel hybrid cuprous iodide crystal material Cu2I2 (C 11 H8N) crystallographic data

[0061]

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel hybrid cuprous iodide luminescent material, characterized in that: The molecular structural formula of the luminescent material is Cu4I4(1-(4-pyridinyl)piperazine)2 or Cu2I2(2-(4-bromophenyl)pyridine)2; Wherein, the luminescent material Cu4I4(1-(4-pyridinyl)piperazine)2 is a two-dimensional double-layer network structure; The luminescent material Cu2I2(2-(4-bromophenyl)pyridine)2 is a one-dimensional chain structure.

2. The luminescent material according to claim 1, characterized in that: The Cu4I4(1-(4-pyridinyl)piperazine)2 is a monoclinic crystal with a P2 / c space group and a unit cell parameter of α=90°,β=97.758(2)°,γ=90°,unit cell volume 3. The luminescent material according to claim 1, characterized in that: The four Cu + With four I - The cubic Cu4I4 clusters were formed, and each 1-(4-pyridyl)piperazine ligand was bonded to two Cu on two Cu4I4 clusters. + Coordination; Each Cu4I4 cluster is coordinated with four 1-(4-pyridyl)piperazines, and the 1-(4-pyridyl)piperazines are arranged in an up-and-down staggered manner, together forming a two-dimensional double-layer network structure.

4. The luminescent material according to claim 1, characterized in that: The Cu2I2(2-(4-bromophenyl)pyridine)2 is a monoclinic crystal with a P21 / n space group and a unit cell parameter of α=90°,β=93.184(17)°,γ=90°,unit cell volume 5. The luminescent material according to claim 1, characterized in that: The luminescent material Cu2I2(2-(4-bromophenyl)pyridine)2 + with I - The ladder-like inorganic grid clusters were formed in a 1:1 ratio, with 2-(4-bromophenyl)pyridine ligand and a Cu + Coordinate to form a one-dimensional chain structure.

6. A method for preparing the luminescent material according to claim 1, characterized in that: The method comprises the following steps: placing cuprous iodide solution as a bottom solution, an aqueous solution as a buffer solution and an organic ligand solution as a top solution in a reaction container in sequence, sealing the container and allowing the container to react, and after the reaction is completed, taking out the crystals, washing them and drying them to obtain the luminescent material.

7. The preparation method according to claim 6, characterized in that: The molar ratio of the organic ligand to cuprous iodide is 1:1 to 3; The preparation process of the cuprous iodide solution is as follows: taking excess potassium iodide and dissolving it in deionized water, filtering to obtain a saturated potassium iodide aqueous solution, and dissolving cuprous iodide under ultrasound to obtain a cuprous iodide solution.

8. The preparation method according to claim 6, characterized in that: The organic ligand is selected from at least one of 2-(4-bromophenyl)pyridine and 1-(4-pyridyl)piperazine.

9. The preparation method according to claim 6, characterized in that: The preparation process of the aqueous solution is as follows: deionized water and an organic solvent are mixed, wherein the volume ratio of the deionized water to the organic solvent is 1:1; The preparation process of the organic ligand solution is as follows: dissolving an organic ligand in an organic solvent to obtain; Each of the organic solvents is independently selected from at least one of i-PrOH, EtOH, MeOH, TFE, HFIP, DCM, hexane, THF, toluene or benzene; The buffer layer solution is slowly dripped onto the surface of the bottom solution; The top layer solution is slowly dripped onto the surface of the buffer layer solution.

10. Use of the luminescent material according to claim 1 in the preparation of solid-state lighting materials, light-emitting devices, security and anti-counterfeiting materials, lasers and phosphors.

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