Preparation and application of zero-dimensional manganese-based organic-inorganic hybrid metal halide

Abstract

The invention relates to the technical field of metal halide light-emitting functional crystals, and discloses preparation and application of a zero-dimensional manganese-based organic-inorganic hybrid metal halide, and a specific preparation method comprises the following steps: respectively adding N, N, N ', N'-tetramethyl-1, 3-propane diamine and a manganese-containing compound into hydrobromic acid, and heating until the materials are completely dissolved; standing the solution, cooling and crystallizing; and after the reaction is completed, removing the redundant solution, and drying the obtained crystal in a drying oven to obtain the zero-dimensional manganese-based organic-inorganic hybrid metal halide. Lead is replaced by manganese, so that the environment-friendly zero-dimensional organic-inorganic hybrid metal halide is successfully constructed; the problems of toxicity and stability of the lead-based material are solved; the compound has excellent optical performance, the photoluminescence efficiency is 79.04%, a wide light absorption range is shown, and efficient green light emission of 525 nm can be achieved under ultraviolet excitation.

Description

Technical Field

[0001] The present invention relates to the technical field of metal halide luminescent functional crystals, and particularly relates to the preparation and application of a zero-dimensional manganese-based organic-inorganic hybrid metal halide. Background Art

[0002] Organic-inorganic hybrid metal halides, as materials with special structures and properties, are composed of organic cations and metal halide polyhedra or polymers in the inorganic part, where the metal halide polyhedra or polymers are usually composed of metal ions and halogen anions (such as chlorine, bromine, or iodine). Due to the diverse selectivity of organic cations, organic-inorganic hybrid metal halides have rich chemical compositions and structural compositions. Among them, lead-based organic-inorganic hybrid metal halides are considered highly promising luminescent materials due to their large absorption coefficient, high carrier mobility, high photoluminescence quantum yield (PLQY), and simple preparation with low cost. However, the toxicity and stability of lead are currently urgent problems to be solved. Thanks to the rich chemical combinations, organic-inorganic hybrid metal halides not only have a rich selection of organic cations but also a rich selection of metal ions. Therefore, environmentally friendly organic-inorganic hybrid metal halides with excellent stability can be constructed by selecting environmentally friendly metal ions.

[0003] Currently, metal ions with d 5 , d 10 and ns 2 configurations have been used to construct environmentally friendly organic-inorganic hybrid metal halides with excellent luminescent properties. By regulating the coordination mode of organic cations and metal halide polyhedra or polymers, rich crystal structures from zero-dimensional (0D) to three-dimensional (3D) can be constructed. Compared with metal halides of other dimensions, the completely isolated polyhedral units in 0D metal halides make excitons more localized, thus having stronger quantum confinement. And the more localized environment can effectively increase the radiation probability, thereby enabling a PLQY close to 100%. Among them, as an environmentally friendly metal ion, manganese-based 0D organic-inorganic hybrid metal halides have received extensive attention. In manganese-based 0D organic-inorganic hybrid metal halides, isolated tetrahedra are separated and surrounded by organic cations with inherent quantum confinement, effectively suppressing the transfer of excitation energy between adjacent Mn 2+ ion luminescence centers, thus enabling efficient luminescence. This excellent luminescent property makes environmentally friendly manganese-based 0D organic-inorganic hybrid metal halides have broad application prospects in the field of luminescence. Summary of the Invention

[0004] The purpose of the present invention is to solve the drawbacks existing in the prior art, and to propose the preparation and application of a zero-dimensional manganese-based organic-inorganic hybrid metal halide.

[0005] To achieve the above object, the present invention adopts the following technical solutions: The preparation of a zero-dimensional manganese-based organic-inorganic hybrid metal halide is carried out by cooling crystallization method with N,N,N',N'-tetramethyl-1,3-propanediamine (C 7 H 20 N 2 ) and manganese-containing compounds in the reaction solvent hydrobromic acid (HBr).

[0006] Preferably, the manganese-containing compound is one of manganese bromide, manganese oxide, manganese hydroxide, manganese carbonate, and manganese acetate.

[0007] Preferably, the specific preparation method of the zero-dimensional manganese-based organic-inorganic hybrid metal halide includes the following steps: S1. Solution preparation: Add N,N,N',N'-tetramethyl-1,3-propanediamine (C 7 H 20 N 2 ) and manganese-containing compounds with a molar ratio of 1:1 to hydrobromic acid (HBr) respectively, and heat to complete dissolution; S2. Reaction process: At room temperature, let the solution after complete dissolution in step S1 stand still and carry out cooling crystallization to obtain large (C 7 H 20 N 2 )MnBr 3 crystals; S3. Product collection: After the reaction is completed, remove the excess solution, and place the crystals obtained in step S2 in an oven for drying to obtain the zero-dimensional manganese-based organic-inorganic hybrid metal halide.

[0008] Preferably, in step S3, the temperature in the oven is 70 °C.

[0009] Preferably, the zero-dimensional manganese-based organic-inorganic hybrid metal halide belongs to the orthorhombic crystal system, the space group is Pnma, and the unit cell parameters are: a = 20.4457 Å, b = 20.4457 Å, c = 7.7938 Å, α = β = γ = 90°.

[0010] The above-prepared zero-dimensional manganese-based organic-inorganic hybrid metal halide is applied in the fields of lighting, display, anti-counterfeiting, encryption, X-ray imaging, etc.

[0011] The beneficial effects of the present invention are as follows: 1. The present invention successfully constructs an environmentally friendly zero-dimensional organic-inorganic hybrid metal halide by substituting manganese for lead, solving the toxicity and stability problems of lead-based materials.

[0012] 2. The zero-dimensional manganese-based organic-inorganic hybrid metal halide (C 7 H 20 N 2 )MnBr 3 prepared by the present invention has excellent optical properties, with a photoluminescence efficiency of 79.04%, exhibits a wide light absorption range, and can achieve efficient green light emission at 525 nm under ultraviolet light excitation.

[0013] 3. The present invention uses a simple cooling crystallization method to prepare the zero-dimensional manganese-based organic-inorganic hybrid metal halide (C 7 H 20 N 2 )MnBr 3 material. The process is simple, the cost is low, it is suitable for large-scale production, and has high industrialization potential.

[0014] 4. The zero-dimensional manganese-based organic-inorganic hybrid metal halide (C 7 H 20 N 2 )MnBr 3 material prepared by the present invention with the characteristics of efficient green light emission has broad application prospects in the fields of lighting, display, anti-counterfeiting, encryption, X-ray imaging, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 、Comparison diagram of the experimental X-ray powder diffraction pattern and the theoretical fitting X-ray powder diffraction pattern of (C 7 H 20 N 2 )MnBr 3 ; Figure 2 、Schematic diagram of the crystal structure of (C 7 H 20 N 2 )MnBr 3 ; Figure 3 、UV-Vis absorption spectrum of (C 7 H 20 N 2 )MnBr 3 ; Figure 4 、Excitation and emission spectra of (C 7 H 20 N 2 )MnBr 3 ; Figure 5 、(C 7 H 20 N 2 )MnBr 3Luminescent chromaticity coordinate (CIE) diagram, with an inset showing a working photo of a light-emitting diode; Figure 6 , (C 7 H 20 N 2 )MnBr 3 X-ray imaging applications of the film prepared by combining with polydimethylsiloxane (PDMS). Detailed implementation manners

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0017] Example 1: S1. Solution preparation: Add 1 mol of N,N,N',N'-tetramethyl-1,3-propanediamine (C 7 H 20 N 2 ) and 1 mol of manganese bromide into 10 mL of hydrobromic acid (HBr) respectively, and heat until completely dissolved.

[0018] S2. Reaction process: At room temperature, let the completely dissolved solution stand still for cooling crystallization to obtain large (C 7 H 20 N 2 )MnBr 3 crystals.

[0019] S3. Product collection: After the reaction is completed, remove the excess solution, and then dry the crystals in an oven at 70 °C.

[0020] Characterization results: The zero-dimensional manganese-based organic-inorganic hybrid metal halide (C 7 H 20 N 2 )MnBr 3 prepared in Example 1 was subjected to a comparison between the experimental X-ray powder diffraction pattern and the theoretical simulated X-ray powder diffraction pattern of the single crystal structure. As Figure 1 shown, the experimental X-ray powder diffraction pattern of (C 7 H 20 N 2 )MnBr 3 has good consistency with the theoretically fitted X-ray powder diffraction pattern, proving the phase purity of (C 7 H 20 N 2 )MnBr 3 prepared by the cooling crystallization method provided by the present invention. As Figure 2 shown, (C 7 H 20 N2 )MnBr 3 is composed of an organic part C 7 H 20 N 2 and [MnBr 4 2- tetrahedra. Among them, the [MnBr 4 2- tetrahedron is surrounded and separated by C 7 H 20 N 2 to form a typical zero-dimensional organic-inorganic hybrid metal halide structure. It belongs to the orthorhombic crystal system, the space group is Pnma, and the unit cell parameters are: a = 20.4457 Å, b = 20.4457 Å, c = 7.7938 Å, α = β = γ = 90°.

[0021] Example 2: S1. Solution preparation: Add 2 mol of N,N,N',N'-tetramethyl-1,3-propanediamine (C 7 H 20 N 2 )and 2 mol of manganese oxide into 20 mL of hydrobromic acid (HBr) respectively, and heat until completely dissolved.

[0022] S2. Reaction process: At room temperature, let the completely dissolved solution stand still and cool to crystallize to obtain large (C 7 H 20 N 2 )MnBr 3 crystals.

[0023] S3. Product collection: After the reaction is completed, remove the excess solution, and then dry the crystals in an oven at 70 °C.

[0024] Characterization results: The zero-dimensional manganese-based organic-inorganic hybrid metal halide (C 7 H 20 N 2 )MnBr 3 prepared in Example 2 was collected for ultraviolet-visible absorption spectroscopy. As Figure 3 shown, (C 7 H 20 N 2 )MnBr 3 has multiple obvious absorption peaks in the ultraviolet-visible region. This indicates that the (C 7 H 20 N 2 )MnBr 3 designed and prepared in this invention not only has good absorption ability for ultraviolet light, but also has good absorption performance for visible light.

[0025] ​​Example 3: S1. Solution preparation: Add 3 mol of N,N,N',N'-tetramethyl-1,3-propanediamine (C 7 H 20 N 2 )) and 3 mol of manganese hydroxide to 30 mL of hydrobromic acid (HBr) respectively, and heat until completely dissolved.

[0026] S2. Reaction process: At room temperature, let the completely dissolved solution stand still for cooling crystallization to obtain large pieces of (C 7 H 20 N 2 ))MnBr 3 crystals.

[0027] S3. Product collection: After the reaction is completed, remove the excess solution, and then dry the crystals in an oven at 70 °C.

[0028] Characterization results: The zero-dimensional manganese-based organic-inorganic hybrid metal halide (C 7 H 20 N 2 ))MnBr 3 prepared in Example 3 was subjected to collection of excitation and emission spectra. As Figure 4 shown, the excitation spectrum shows that (C 7 H 20 N 2 ))MnBr 3 has multiple absorption peaks in the range of 250 - 500 nm, which indicates that the (C 7 H 20 N 2 ))MnBr 3 designed and prepared in the present invention can not only be excited by ultraviolet light, but also by some visible light. By excitation with 362 nm ultraviolet light, a narrow-band green light emission with a peak position at 525 nm is obtained, and the PLQY can reach 79.04%. As Figure 5 shown, the inset is the luminescence image of the (C 7 H 20 N 2 ))MnBr 3 single crystal under 365 nm ultraviolet light irradiation, and the color coordinates (CIE) corresponding to the green luminescence are (0.239, 0.696). This indicates that the highly efficient green luminescent (C 7 H 20 N 2 ))MnBr 3 material designed and prepared in the present invention is a luminescent material with great application prospects.

[0029] Example 4: S1. Solution preparation: Add 4 mol of N,N,N',N'-tetramethyl-1,3-propanediamine (C 7H 20 N 2 (), and 4 mol of manganese hydrogencarbonate are added to 40 mL of hydrobromic acid (HBr) and heated until completely dissolved.

[0030] S2. Reaction process: At room temperature, the completely dissolved solution is allowed to stand for cooling crystallization to obtain large pieces of (C 7 H 20 N 2 )MnBr 3 crystals.

[0031] S3. Product collection: After the reaction is completed, after removing the excess solution, the crystals are placed in an oven at 70 °C for drying.

[0032] Example 5: S1. Solution preparation: 5 mol of N,N,N',N'-tetramethyl-1,3-propanediamine (C 7 H 20 N 2 ) and 5 mol of manganese acetate are added to 50 mL of hydrobromic acid (HBr) and heated until completely dissolved.

[0033] S2. Reaction process: At room temperature, the completely dissolved solution is allowed to stand for cooling crystallization to obtain large pieces of (C 7 H 20 N 2 )MnBr 3 crystals.

[0034] S3. Product collection: After the reaction is completed, after removing the excess solution, the crystals are placed in an oven at 70 °C for drying.

[0035] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A preparation method of a zero-dimensional manganese-based organic-inorganic hybrid metal halide, characterized in that: The product is prepared by cooling crystallization method with N,N,N',N'-tetramethyl-1,3-propylenediamine and a manganese-containing compound in hydrobromic acid as a reaction solvent.

2. The preparation of a zero-dimensional manganese-based organic-inorganic hybrid metal halide according to claim 1, characterized in that: The manganese-containing compound is one of manganese bromide, manganese oxide, manganese hydroxide, manganese carbonate and manganese acetate.

3. The preparation of a zero-dimensional manganese-based organic-inorganic hybrid metal halide according to claim 1, characterized in that: The specific method for preparing the zero-dimensional manganese-based organic-inorganic hybrid metal halide comprises the following steps: S1. Solution preparation: Add N,N,N',N'-tetramethyl-1,3-propylenediamine and a manganese-containing compound in a molar ratio of 1:1 to hydrobromic acid and heat until completely dissolved; S2. Reaction process: At room temperature, the solution after complete dissolution in step S1 was allowed to stand for cooling and crystallization to obtain a large block (C7H 20 N2) MnBr3 crystal; S3. Product collection: After the reaction is completed, the excess solution is removed and the crystals obtained in step S2 are placed in an oven for drying to obtain the zero-dimensional manganese-based organic-inorganic hybrid metal halide.

4. The preparation of a zero-dimensional manganese-based organic-inorganic hybrid metal halide according to claim 3, characterized in that: In step S3, the temperature in the oven is 70°C.

5. The preparation of a zero-dimensional manganese-based organic-inorganic hybrid metal halide according to claim 3, characterized in that: The zero-dimensional manganese-based organic-inorganic hybrid metal halide belongs to the orthorhombic crystal system, the space group is Pnma, and the unit cell parameters are: a = 20.4457 Å, b = 20.4457 Å, c = 7.7938 Å, α = β = γ = 90°.

6. Application of the zero-dimensional manganese-based organic-inorganic hybrid metal halide prepared as claimed in claim 3 in the fields of lighting, display, anti-counterfeiting, encryption, and X-ray imaging.

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