Organic-inorganic hybrid white-light fluorescent material with Cu (I) as light-emitting center and preparation method of organic-inorganic hybrid white-light fluorescent material

Abstract

The invention discloses an organic-inorganic hybrid white light fluorescent material taking Cu (I) as a luminescence center, the chemical composition of the material is ACuX3, A represents positive divalent methyl phenyl piperazine cation [C11H18N2] < 2 + >, X is halogen ion Br <-> or I <->; a copper source, hydrogen bromide or hydrogen iodide and 1-phenylpiperazine or 1-phenylpiperazine salt are subjected to solvothermal reaction in methanol to prepare the 1-phenylpiperazine. The excitation wavelength of the material is 290-320 nm, the emission wavelength is 400-650 nm, the material belongs to a fluorescent material for emitting white light, the spectrum half-peak width is about 170 nm, the emission wavelength range is wide, the air stability and the thermal stability are good, the fluorescence performance is excellent, and the material has wide application prospects in the field of white light LEDs. The preparation method of the fluorescent material is easy and convenient to operate, the fluorescent material has good stability, meanwhile, the toxic element lead is replaced with the metal element copper, and harm to the human body and pollution to the environment are reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of fluorescent materials, and in particular relates to an organic-inorganic hybrid white light fluorescent material with Cu(I) as a luminescent center and a preparation method thereof. Background Art

[0002] White light LEDs have rapidly replaced traditional incandescent and fluorescent lamps due to their outstanding advantages such as high color rendering index, fast response, energy saving and environmental protection, and have become a new generation of solid-state lighting display light sources. White light LED devices can obtain white light by selecting three different colors of phosphors (blue, green, and red) and exciting the three-color mixed phosphors with commercial chips of corresponding wavelengths. However, due to the energy transfer and different attenuation rates between these different phosphors, the emission spectrum of the device will change, and the output spectrum will be discontinuous, resulting in low luminous efficiency and unstable light color. Single-component white light emitting materials can not only overcome this shortcoming and output a continuous spectrum with a wide coverage range, but also have the advantages of low cost, simple manufacturing process, and good stability. Therefore, it is very necessary to develop single-component white light emitting materials.

[0003] Organic-inorganic hybrid materials have good electronic transition ability and can achieve tunable white light emission in the entire visible spectrum by simply adjusting the composition of mixed halide perovskites. They can be combined with current commercial LED chips to form white light LED devices, which has gradually become a highlight of people's research. However, since this mixture has two different components, strong self-absorption will occur between the two parts, which limits their practical application. STE broadband emission in mixed perovskites can achieve a large Stokes shift, avoid self-absorption, and maintain a short decay time. Therefore, this type of single-component broadband white light emitting perovskite material is a good choice for white light solid-state lighting. At present, organic-inorganic hybrid white light emitting materials have made great progress in continuous research. However, the types of A-site organic amine ions that can be used as white light emitters in organic-inorganic hybrid materials are limited, which greatly limits the development of solid-state lighting materials, and only a few broadband emission perovskite materials have been reported. Therefore, the development of organic-inorganic hybrid white light materials is of great significance. Summary of the invention

[0004] The purpose of the present invention is to provide an organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center, and to provide a preparation method for the fluorescent material.

[0005] For the above purpose, the chemical formula of the white light fluorescent material provided by the present invention is ACuX3, wherein A represents a divalent methylphenylpiperazine cation [C 11 H 18 N2] 2+ , X is a halogen ion Br -or I - The crystal structure of the white light fluorescent material contains an inorganic part [CuX3]2 and an organic part of methylphenylpiperazine. The inorganic part is formed by two CuX3 tetrahedra connected in an XX edge-sharing form to form a zero-dimensional cluster [CuX3]2. Different zero-dimensional clusters are arranged in parallel and filled with divalent methylphenylpiperazine cations.

[0006] In the above chemical formula, when X is Br-, the white light fluorescent material belongs to the monoclinic system. Space group, unit cell parameters are: α=81.281°,β=77.547°,γ=72.775°,unit cell volume

[0007] In the above chemical formula, when X is I - When the white light fluorescent material belongs to the monoclinic system Space group, unit cell parameters are: α=81.595°,β=77.428°,γ=73.097°,unit cell volume

[0008] The excitation wavelength of the fluorescent material of the present invention is 290-320nm, the emission wavelength is 400-650nm, the spectrum half-peak width is 170nm, and it belongs to white light emission.

[0009] The preparation method of the organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescence center of the present invention comprises the following steps: adding a copper source, a hydrohalic acid and an organic ligand into methanol, stirring at room temperature for 0 to 2 hours, reacting at 80 to 150° C. for 24 to 60 hours under closed conditions, slowly cooling to room temperature, precipitating a single crystal from the solution, and ultrasonically washing to obtain the organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescence center.

[0010] The copper source is any one of cuprous oxide, cuprous bromide and cuprous iodide.

[0011] The hydrohalic acid is any one of hydrogen bromide and hydrogen iodide.

[0012] The above-mentioned organic ligand is any one of 1-phenylpiperazine and 1-phenylpiperazine salt.

[0013] The molar ratio of the copper element to the hydrohalic acid and the organic ligand in the copper source is 1:1-1.5:1.5-2.

[0014] In the above-mentioned preparation method, it is further preferred to carry out the reaction at 100 to 120° C. for 48 to 60 hours under a closed condition.

[0015] The beneficial effects of the present invention are as follows:

[0016] 1. Compared with the traditional lead-containing organic-inorganic hybrid luminescent materials, the copper-based organic-inorganic hybrid material of the present invention is non-toxic, has a large bandgap, and has a large separation degree between electrons and holes, and has advantages as a luminescent material. Moreover, this hybrid material has a broadband white light emission of 400 to 650nm, a fluorescence lifetime of microseconds, and has good white light luminescence performance.

[0017] 2. The organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center is synthesized by a solvent thermal method. The method is mild, has good repeatability, and the raw materials used are in sufficient reserves and low in price, and is expected to be commercially applicable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 [C] prepared in Example 1 11 H 18 Diagram of the smallest structural unit of N2](CuBr3) material.

[0019] Figure 2 [C] prepared in Example 1 11 H 18 Crystal structure diagram of N2](CuBr3) material.

[0020] Figure 3 [C] prepared in Example 2 11 H 18 Diagram of the smallest structural unit of N2](CuI3) material.

[0021] Figure 4 [C] prepared in Example 2 11 H 18 Crystal structure diagram of N2](CuI3) material.

[0022] Figure 5 [C] prepared in Example 1 11 H 18 N2](CuBr3) material and [C 11 H 18 Powder XRD comparison diagram of N2](CuI3) materials.

[0023] Figure 6 [C] prepared in Example 1 11 H 18 N2](CuBr3) material and [C 11 H 18 Ultraviolet absorption edge and energy band diagram of N2](CuI3) material.

[0024] Figure 7 [C] prepared in Example 1 11 H 18N2](CuBr3) material temperature-dependent photoluminescence spectrum performance test diagram.

[0025] Figure 8 [C] prepared in Example 2 11 H 18 N2](CuI3) material temperature-dependent photoluminescence spectrum performance test diagram.

[0026] Fig. 9 [C] prepared in Example 1 11 H 18 N2](CuBr3) material and [C 11 H 18 Fluorescence lifetime performance test diagram of N2](CuI3) material.

[0027] Fig.10 [C] prepared in Example 1 11 H 18 N2](CuBr3) material LED device performance test chart.

[0028] Fig.11 [C] prepared in Example 2 11 H 18 N2](CuI3) material LED device performance test chart. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments, but the protection scope of the present invention is not limited to these embodiments.

[0030] Example 1

[0031] 0.1431g (1mmol) Cu2O, 0.3245g (2mmol) 1-phenylpiperazine, 0.3236g (4mmol) hydrogen bromide, and 8mL methanol were added to a polytetrafluoroethylene reactor, stirred at room temperature for 1 hour, and then the polytetrafluoroethylene reactor was sealed and the steel sleeve was tightened, and the reactor was placed in an oven, and the reaction was carried out at a constant temperature of 100°C for 48 hours. After the reaction was completed, the temperature was slowly lowered at room temperature, and single crystals were precipitated from the solution. The single crystals were ultrasonically washed with methanol for many times to obtain a colorless copper-based organic-inorganic hybrid material, whose chemical formula is [C 11 H 18 N2](CuBr3), where C 11 H 18 N2 represents a divalent methylphenylpiperazine cation. Single crystal X-ray diffraction analysis of the material shows that [C 11 H 18 N2](CuBr3) crystallizes in the monoclinic system Space group, unit cell parameters are: α=81.281°,β=77.547°,γ=72.775°,unit cell volume Depend on Figure 1 It can be seen that [C 11 H 18 The crystal structure of N2](CuBr3) contains an inorganic part [CuBr3]2 and an organic part methylphenylpiperazine. The inorganic part is a zero-dimensional [CuBr3]2 cluster formed by two CuBr3 tetrahedra connected by a shared Br-Br edge, such as Figure 2 As shown, the [CuBr3]2 clusters are arranged in parallel and staggered, and are filled with divalent methylphenylpiperazine cations.

[0032] Example 2

[0033] 0.1431g (1mmol) Cu2O, 0.3245g (2mmol) 1-phenylpiperazine, 0.5116g (4mmol) hydrogen iodide, and 8mL methanol were added to a polytetrafluoroethylene reactor, stirred at room temperature for 1 hour, and then the polytetrafluoroethylene reactor was sealed and the steel sleeve was tightened, and the reactor was placed in an oven, and reacted at 100°C for 48 hours. After the reaction was completed, the temperature was slowly lowered at room temperature, and single crystals were precipitated from the solution. The single crystals were ultrasonically washed with methanol for many times to obtain a colorless copper-based organic-inorganic hybrid material, whose chemical formula is [C 11 H 18 N2](CuI3), where C 11 H 18 N2 represents a divalent methylphenylpiperazine cation. Single crystal X-ray diffraction analysis of the material shows that [C 11 H 18 N2](CuI3) crystallizes in the monoclinic system Space group, unit cell parameters are: α=81.595°,β=77.428°,γ=73.097°,unit cell volume Depend on Figure 3 It can be seen that [C 11 H 18 The crystal structure of N2](CuI3) contains an inorganic part [CuI3]2 and an organic part of methylphenylpiperazine cation. The inorganic part is a zero-dimensional [CuI3]2 cluster formed by two CuI3 tetrahedra connected by a shared II edge, such as Figure 4 As shown, the [CuI3]2 clusters are arranged in parallel and staggered, and are filled with divalent methylphenylpiperazine cations.

[0034] according to Figure 5 The powder XRD test results show that the XRD spectra of the copper-based organic-inorganic hybrid materials prepared in Examples 1 and 2 correspond well to the simulated XRD spectra of their single crystals, indicating that the materials are of high purity. Figure 6 The UV-visible absorption spectrum and band gap show that the material has a large band gap and a large degree of separation and recombination of electron-hole pairs, making it suitable as a luminescent material. Figure 7 The temperature-dependent photoluminescence spectrum performance test diagram shows that the [C 11 H 18 N2](CuBr3) material has a continuous emission wavelength range from 400 to 620nm at different temperatures, and the emission intensity gradually increases as the temperature decreases. Figure 8 It can be seen that [C 11 H 18 At different temperatures, when the excitation wavelength is 330nm, the emission wavelength of N2](CuI3) material has a continuous coverage from 400 to 650nm, and the emission intensity gradually increases as the temperature decreases. Fig. 9 It can be seen that the fluorescence lifetime of the white light fluorescent materials prepared in Example 1 and Example 2 is both in the microsecond level, which has advantages in preparing white light LEDs. The fluorescent materials in Example 1 and Example 2 are prepared into white light LED devices. Figures 10-11 It can be seen that the fluorescent materials of Examples 1 to 2 are used as white light phosphors. After being made into LED devices, the devices emit bright white light with a moderate color temperature. 11 H 18 Devices made of N2](CuI3) material have a high color rendering index (CRI>80).

Claims

1. An organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center, characterized in that: The chemical composition of the white light fluorescent material is A(CuX3), wherein A is a divalent methylphenylpiperazine cation [C 11 H 18 N2] 2+ , X is a halogen ion Br - or I - ; When X is Br - When the white light fluorescent material belongs to the monoclinic system Space group, unit cell parameters are: α=81.281°,β=77.547°,γ=72.775°,unit cell volume When X is I - When the white light fluorescent material belongs to the monoclinic system Space group, unit cell parameters are: α=81.595°,β=77.428°,γ=73.097°,unit cell volume 2. The organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center according to claim 1, characterized in that: The crystal structure of the white light fluorescent material contains an inorganic part [CuX3]2 and an organic part of methylphenylpiperazine. The inorganic part is formed by two CuX3 tetrahedrons connected in an XX co-edge form to form a zero-dimensional cluster [CuX3]2. Different zero-dimensional clusters are arranged in parallel and filled with divalent methylphenylpiperazine cations.

3. The organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center according to claim 1, characterized in that: The excitation wavelength of the white light fluorescent material is 290-320 nm, the emission wavelength is 400-650 nm, and the spectrum half-peak width is 170 nm.

4. A method for preparing the organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center according to claim 1, characterized in that: A copper source, a hydrohalic acid and an organic ligand are added to methanol, stirred at room temperature for 0 to 2 hours, then reacted at 80 to 150° C. for 24 to 60 hours under a closed condition, cooled to room temperature, and ultrasonically washed to obtain an organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center; The copper source is any one of cuprous oxide, cuprous bromide and cuprous iodide; The above-mentioned hydrohalic acid is any one of hydrogen bromide and hydrogen iodide; The organic ligand is any one of 1-phenylpiperazine and 1-phenylpiperazine salt.

5. The method for preparing the organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center according to claim 4, characterized in that: The molar ratio of the copper element in the copper source to the hydrohalic acid and the organic ligand is 1:1-1.5:1.5-2.

6. The method for preparing the organic-inorganic hybrid white light fluorescent material with Cu(I) as the luminescent center according to claim 4, characterized in that: The reaction is carried out at 100-120°C under closed conditions for 48-60 hours.

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