Sulfur-coordinated manganese halide complexes, methods of making and using the same

Abstract

The application provides a kind of sulfur-coordinated manganese halide complex and a preparation method and application thereof, and belongs to the technical field of luminescent materials.The complex is an ionic luminescent complex formed by coordination and combination of triphenyl sulfonium salt as an organic ligand and manganese halide ion.The preparation process is simple, the cost is low, the complex itself has excellent photophysical properties, weak self-absorption and high light quantum yield, and emits green light in solid state;It can be used as fluorescent powder in the fields of anti-counterfeiting printing, lighting display, etc.;The thin film prepared based on the complex can also be used as a luminescent layer in OLED devices;And because the complex has excellent X-ray response performance, it has certain potential in the fields of X-ray imaging and detection, and has wide application prospects.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of luminescent materials, and particularly relates to a kind of sulfur-coordinated manganese halide complexes and a preparation method and application thereof. BACKGROUND

[0002] In recent years, due to the increasing demand of application in various fields, X-ray detection technology has attracted extensive research interest and rapid development. X-ray detectors can be divided into direct detectors and indirect detectors according to the working principle. In the indirect detector, the high-energy X-ray photons are converted into visible light signals by the scintillator, and these photons can be further detected by amorphous silicon photodiodes or photomultiplier tubes and imaged. Therefore, the scintillator material is the core component of the X-ray detector.

[0003] At present, commercial scintillators can be divided into inorganic scintillators and organic scintillators. High-efficiency inorganic single-crystal scintillators, such as Bi4Ge3O 12 (BGO), Lu3A5O 12 :Ce 3+ (LuAG:Ce) and CsI:TI, are widely used in X-ray detection due to their high light yield, suppression of optical crosstalk and strong light capacity. However, traditional inorganic scintillator materials usually exist in the form of large-size crystals, which have defects such as complex manufacturing process, high temperature in preparation process, long time consumption and difficult to tune luminescence. At the same time, organic scintillator materials with fast decay time and low-cost preparation process have attracted the attention of those skilled in the art, but the low X-ray absorption coefficient often leads to poor performance of organic scintillators. Therefore, it is urgent to explore a new type of scintillator material with simple preparation process and high X-ray detection efficiency.

[0004] Organic-inorganic hybrid metal halides have triggered a research boom in the field of scintillators due to their simple low-temperature solution preparation process, excellent scintillation performance and rich crystal structure flexibility. Among them, manganese-based halide materials have the advantages of high photoluminescence efficiency, easy synthesis, excellent photoelectric properties, high stability, low toxicity and high abundance. On this basis, the selection of organic cations is particularly important for the construction of manganese-based halide luminescent materials. At present, the organic ligands of organic-inorganic hybrid metal halides are mostly organic molecules containing nitrogen, phosphorus or phosphorus oxide, and the selection of ligand organic cations is still in the stage of a large number of attempts and blind selection. There is still a lot of research space for such complex materials.

[0005] Therefore, it is still a major challenge to select appropriate organic molecules for the construction of high-performance manganese-based metal halide luminescent materials. The development of corresponding complexes can provide new ideas for expanding the types of complexes and scintillators, and has important theoretical research significance and practical application value. SUMMARY

[0006] The present application aims at solving the problems in the prior art, and provides a kind of sulfur-coordinated manganese halide complex and a preparation method thereof, and the present application selects triphenyl sulfonium salt as organic ligand, and combines with manganese halide to form ion luminescence type manganese halide complex, the complex has weak self-absorption, high radiation luminescence intensity, and has excellent X-ray imaging performance, and has wide application potential in many fields.

[0007] The specific technical scheme of the present application is as follows: a kind of sulfur-coordinated manganese halide complex, which is an ion luminescence complex formed by coordination of triphenyl sulfonium salt as organic ligand and manganese halide ion, and its structure general formula is as follows:

[0008]

[0009] A is selected from any one of the following groups:

[0010]

[0011] B is selected from any one of the following groups:

[0012]

[0013] Further, the sulfur-coordinated manganese halide complex emits green light in solid state, and has weak self-absorption and high radiation luminescence intensity.

[0014] The preparation method of the above-mentioned sulfur-coordinated manganese halide complex is as follows: weigh manganese halide MnX2 and triphenyl sulfonium salt, mix them, dissolve them with organic solvent, heat and evaporate, and then precipitate crystals to obtain the sulfur-coordinated manganese halide complex, and the preparation route is as follows:

[0015]

[0016] Wherein, X is Cl or Br.

[0017] Further, the molar ratio of MnX2 and triphenyl sulfonium salt is 1-4:2-8.

[0018] Further, the organic solvent is ethanol, and the evaporation temperature is 60-80 DEG C.

[0019] The scintillator thin film prepared from the above-mentioned sulfur-coordinated manganese halide complex does not emit light under sunlight, emits green light under ultraviolet and X-ray irradiation, and can be successfully applied in X-ray detection and imaging field based on its responsiveness to X-ray.

[0020] The above-mentioned sulfur-coordinated manganese halide complex can be applied in OLED devices, and specifically, the sulfur-coordinated manganese halide complex can be prepared into a thin film by vacuum evaporation method, and the thin film can be applied as a luminescent layer in OLED devices.

[0021] Based on the solid-state luminescent characteristics of the above-mentioned sulfur-coordinated manganese halide complexes, the complexes can be ground into powder as fluorescent powder and applied in the field of solid-state lighting or optoelectronic display.

[0022] Compared with the prior art, the present application has the following advantages:

[0023] 1. The sulfur-coordinated manganese halide complexes disclosed in the present application have excellent photophysical properties, green light emission in solid state, weak self-absorption and high light quantum yield;

[0024] 2. The sulfur-coordinated manganese halide complexes disclosed in the present application have excellent response performance to X-rays, low detection limit and high light yield, and can be prepared into scintillator thin films and applied in the field of X-ray detection and imaging;

[0025] 3. The sulfur-coordinated manganese halide complexes disclosed in the present application emit green light when prepared into thin films and applied in OLED devices as light-emitting layers;

[0026] 4. Based on the solid-state luminescent characteristics of the sulfur-coordinated manganese halide complexes disclosed in the present application, the complexes can be ground into powder as fluorescent powder and applied in the field of solid-state lighting or optoelectronic display, or mixed with organic solvents to be used as ink in the field of printing or printing;

[0027] 5. The preparation method of the sulfur-coordinated manganese halide complexes disclosed in the present application is simple, the complexes are synthesized by "solution method", the preparation cost is low, the complexes have the characteristics of low toxicity and environmental protection, and the complexes are easy to mass-produce and apply. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a single crystal structure diagram of complex I;

[0029] Figure 2 It is a single crystal XRD powder diffraction diagram of complex I;

[0030] Figure 3 It is a single crystal structure diagram of complex II;

[0031] Figure 4 It is a single crystal XRD powder diffraction diagram of complex II;

[0032] Figure 5 It is an absorption coefficient and photon energy spectrum diagram of high-energy X-rays of complex I and complex II;

[0033] Figure 6 It is a normalized solid-state emission spectrum of complex I;

[0034] Figure 7 It is a normalized solid-state emission spectrum of complex II;

[0035] Figure 8 Emission spectra of complex I (a), complex II (b) under X-ray irradiation at different doses;

[0036] Figure 9 X-ray linear response spectra of complex I (a), complex II (b);

[0037] Figure 10 Normalized excitation-emission spectra of complex I;

[0038] Figure 11 Normalized excitation-emission spectra of complex II;

[0039] Figure 12 CIE 1931 chromaticity diagram of complex I;

[0040] Figure 13 CIE 1931 chromaticity diagram of complex II;

[0041] Figure 14 Spectrogram of the relationship between the decay coefficient and the thickness of complex I, complex II after X-ray absorption;

[0042] Figure 15 Irradiation luminescence intensity diagram of complex II and inorganic scintillator LuAG:Ce;

[0043] Figure 16 Imaging diagram of a chip under X-ray irradiation by a scintillator thin film prepared based on complex II;

[0044] Figure 17 Imaging diagrams of a spring under X-ray irradiation by scintillator thin films prepared based on complex I and complex II, respectively;

[0045] Figure 18 Simple schematic diagram of an X-ray imaging device, wherein 1 is an X-ray tube, 2 is a sample, 3 is a scintillator, 4 is a reflector, 5 is a camera, and 6 is a computer;

[0046] Figure 19 Light-emitting diagram of a thin film OLED device prepared based on complex II. DETAILED DESCRIPTION

[0047] The technical solutions of the present application are further described below in conjunction with the drawings, but are not limited thereto, and any modification or equivalent replacement of the technical solutions of the present application without departing from the spirit and scope of the technical solutions of the present application shall be encompassed in the protection scope of the present application.

[0048] Example 1

[0049] The synthesis route of the sulfur-coordinated manganese halide complex I is as follows:

[0050]

[0051] The specific preparation process of complex I is as follows:

[0052] MnCl2(1 mmol) and triphenyl chloride sulfur (1 mmol) are weighed into a 20 mL vial, 5 mL of ethanol is added to dissolve thoroughly, then slowly evaporated at 60°C, and crystals are precipitated after about a week, which is complex I. The single crystal structure diagram of complex I is shown in Figure 1 , and the single crystal XRD powder diffraction diagram of complex I is shown in Figure 2 .

[0053] Example 2

[0054] The synthesis route of sulfur-coordinated manganese halide complex II is as follows:

[0055]

[0056] The specific preparation process of complex II is as follows:

[0057] MnBr2(1 mmol) and triphenyl bromide sulfur (1 mmol) are weighed into a 20 mL vial, 5 mL of ethanol is added to dissolve thoroughly, then slowly evaporated at 60°C, and crystals are precipitated after about a week, which is complex II. The single crystal structure diagram of complex II is shown in Figure 3 , and the single crystal XRD powder diffraction diagram of complex II is shown in Figure 4 .

[0058] Related performance tests

[0059] 1) The absorption coefficient of the complex to high-energy X-rays and the photon energy spectrum can be obtained by measuring the emission spectrum under irradiation, Figure 5 , which are the absorption coefficient and photon energy spectrum diagram of complex I and complex II. From the figure, it can be seen that the X-ray energy range is from 0.001 MeV to 1 MeV, and the absorption coefficient of inorganic scintillator LuAG:Ce, CsI:TI is of the same order of magnitude.

[0060] 2) Figure 6 , Figure 7 The normalized solid-state emission spectrum of complex I and complex II, respectively, is shown in the figure. It can be seen from the figure that the emission characteristic peak of complex I is located at 520 nm, and the emission characteristic peak of complex II is located at 518 nm.

[0061] 3) Figure 8Panels (a) and (b) are the emission spectra of complex I and complex II under different doses of X-rays, respectively. It can be seen from the figures that both complexes show a monotonically increasing emission spectrum under X-ray irradiation (60kV, 0.15μGy / s→3.35μGy / s), and exhibit a good linear response in the range of 0.15μGy / s→3.35μGy / s.

[0062] 4) Figure 9 Panels (a) and (b) show the relationship between irradiation intensity and X-ray dose rate for Complex I and Complex II, respectively. The detection limit was set when the signal-to-noise ratio was equal to 3. The detection limits for Complex I and Complex II were 81.1 nGyaiX / s and 127.2 nGyaiX / s, respectively. These limits are well below the standard limit for medical X-ray diagnosis (5.5 μGyaiX / s).

[0063] 5) The excitation and emission spectra were measured on an Edinburgh FLS-980 spectrophotometer. The emission spectra were obtained using a 460W xenon lamp in the range of 300nm-800nm. The normalized solid-state excitation-emission spectra of complex I and complex II are shown in Figure 2. Figure 10 、 Figure 11 As shown, the emission characteristic peak of complex I is located at 520nm, and the emission characteristic peak of complex II is located at 518nm. The emission bands are consistent with [MnX4] 2- Tetraligand Mn in the unit 2+ Ions 4 T1(G) to 6 A1 radiative transition, the crystal has only one luminescent center, emitting green light. Both have large Stokes shifts, with the Stokes shift of complex I being 70nm and that of complex II being 48nm, showing weak self-absorption.

[0064] 6) The emission spectra of complexes I and II were calculated using CIE 1931 software. The results are shown in Figure 12 and Figure 13 The chromaticity values ​​of complex I and complex II were (0.203, 0.670) and (0.148, 0.697), respectively, both of which are green light.

[0065] 7) The material density data of complex I and complex II were obtained by calculating the X-ray absorption coefficient and XRD characterization experiment, and the curve of the attenuation coefficient of the two complexes after absorbing X-rays with an energy of 60keV as a function of thickness was drawn. The results are shown in Figure 14 ,As can be seen from the figure, the crystal thickness of Complex Ⅰ and Complex Ⅱ is at the same level as the inorganic scintillator LuAG:Ce after 1 mm.

[0066] 8) Comparison chart of light yield of complex II and inorganic scintillator LuAG:Ce under the same dose rate of X-ray irradiation, see the results in Figure 15 As can be seen from the chart, the light yield of complex II is more than twice that of inorganic scintillator LuAG:Ce, which can meet the application requirements of many fields such as space exploration and medical imaging.

[0067] Application Example One

[0068] Based on the unique green light emission and high luminescence quantum efficiency characteristics of complex I and complex II, attempts were made to make scintillator thin films of these two complexes for use in the field of X-ray imaging.

[0069] The film preparation process is as follows: 1g of polymethyl methacrylate (PMMA) is dissolved in 10g of toluene to form a pre-clear solution, then mixed with 0.4g of complex II powder ground three times, stirred uniformly, then titrated on a glass sheet at room temperature for volatilization, obtaining a 1.8mm thick scintillator thin film.

[0070] The scintillator thin film prepared based on complex II does not emit light under daylight, and emits green light under ultraviolet and X-ray irradiation; due to the different absorption of X-rays by different metals, the spatial saturation of the scintillator is different, so it can be used for optical imaging, as shown in Figure 16 Under X-ray irradiation, the chip can be imaged using the thin film, and the clear internal structure of the chip can be observed.

[0071] Based on the same method, a scintillator thin film prepared based on complex I can be obtained, Figure 17 Figures (a) and (b) in the middle are imaging diagrams of the scintillator thin film prepared based on complex I and complex II under X-ray irradiation of a spring, and a very clear spring image can be observed.

[0072] Application Example Two

[0073] The complex II is prepared into a powder, the powder is placed in an evaporation boat, an ITO substrate (ITO facing down) is placed in a vacuum evaporation chamber, the corresponding mask plate is rotated under the substrate, and the ITO surface is shielded with a baffle, and the chamber is vacuumed. Turn on the evaporation power to vacuum coat the evaporation boat. The prepared thin film is applied to the OLED device as a light-emitting layer for light-emitting experiment, Figure 19 That is, the light-emitting diagram, and green light emission is observed. The same phenomenon occurs when the thin film prepared based on complex I is applied to the OLED device.

[0074] Therefore, the thin film material prepared based on complex I and complex II by vacuum evaporation can be applied to OLED devices as a light-emitting layer.

[0075] The above merely illustrates the embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, which are made by using the content of the present application specification and drawings, are also included in the patent protection scope of the present application.

Claims

1. A sulfur-coordinated manganese halide complex characterized by: It is an ionic luminescent complex formed by triphenylsulfonium salt as an organic ligand and coordinated with manganese halide ions. Its general structural formula is as follows: Wherein, A is selected from any one of the following groups: B is selected from any one of the following groups:

2. The sulfur-coordinated manganese halide complex according to claim 1, wherein The sulfur-coordinated manganese halide complex emits green light in the solid state and has weak self-absorption and high irradiation luminescence intensity.

3. The method for preparing the sulfur-coordinated manganese halide complex according to any one of claims 1 to 2, characterized in that: Weigh manganese halide MnX2 and triphenylsulfonium salt, mix them, fully dissolve them in an organic solvent, heat and evaporate them, and precipitate crystals to obtain a sulfur-coordinated manganese halide complex. The preparation route is as follows: Wherein, X is Cl or Br.

4. The method for preparing the sulfur-coordinated manganese halide complex according to claim 3, wherein: The molar ratio of MnX2 to triphenylsulfonate is 1-4:2-8.

5. The method for preparing the sulfur-coordinated manganese halide complex according to claim 4, wherein: The organic solvent is ethanol, and the evaporation temperature is 60-80°C.

6. Use of the sulfur-coordinated manganese halide complex according to any one of claims 1 to 2 in X-ray detection and imaging.

7. Use of the sulfur-coordinated manganese halide complex according to any one of claims 1 to 2 in an OLED device, characterized in that: The sulfur-coordinated manganese halide complex is prepared into a thin film by vacuum evaporation and then the thin film is used as a light-emitting layer in an OLED device.

8. Use of the sulfur-coordinated manganese halide complex according to any one of claims 1 to 2 in solid-state lighting or optoelectronic display.

9. A scintillator thin film, characterized in that: It is prepared based on the sulfur-coordinated manganese halide complex described in any one of claims 1 to 2. The scintillator film does not emit light under sunlight, but emits green light under ultraviolet and X-ray irradiation.

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