Organic-inorganic antimony-based halide luminescent crystal, preparation method and application thereof

Abstract

The invention discloses an organic-inorganic antimony-based halide luminescent crystal as well as a preparation method and application thereof. The chemical formula of the organic-inorganic antimony-based halide luminescent crystal disclosed by the invention is (C6NH8) SbCl4. At room temperature, the crystal belongs to a monoclinic system, and the space group is P21 / c. Specifically, the cell parameters are as follows: a is equal to 12.550 (8), b is equal to 12.832 (2), # imgabs 0 # alpha is equal to 90 degrees, beta is equal to 106.379 (2) degrees, gamma is equal to 90 degrees, Z is equal to 4, and # imgabs 1 #. The organic-inorganic antimony-based halide luminescent crystal can be prepared by adopting a simple volatile solvent method. And a green fluorescent crystal. The preparation method is simple, efficient, high in repeatability, low in cost and mild in reaction condition, and the prepared organic-inorganic antimony-based halide luminescent crystal is high in thermal stability and high in luminescent intensity.

Description

Technical Field

[0001] The present invention relates to the technical field of luminescent crystals and preparation thereof, and in particular to an organic-inorganic antimony-based halide luminescent crystal, a preparation method and application thereof. Background Art

[0002] In recent years, the emerging low-dimensional organic-inorganic hybrid lead-free halide perovskite materials have attracted extensive attention from researchers due to their high photon number, X-ray absorption, high carrier mobility, high luminescence efficiency and structural designability. They have broad application potential in photovoltaic devices, photodetection, light-emitting diodes (LEDs) and sensor technology. The optical properties can be fine-tuned and optimized through delicate structural adjustments, and are particularly outstanding in pressure-induced enhancement and piezoelectric color change.

[0003] Zero-dimensional organic-inorganic hybrid metal halides have gradually attracted attention in the field of X-ray imaging due to their excellent physical properties and luminescence performance, such as non-deliquescent, high stability, no self-absorption, and high luminescence quantum efficiency. They have shown great application potential. Environmentally friendly lead-free metal halide materials such as Sn(Ⅱ), Cu(Ⅰ), and Mn(Ⅱ) have attracted great attention as a new type of luminescent materials due to their excellent optical properties, such as nearly 100% photoluminescence quantum efficiency, large Stokes shift, and reversible photoluminescence properties. However, the luminescence of manganese complexes usually originates from the inherent spin-orbit forbidden dd transition, and the luminescence lifetime is as long as several milliseconds, which cannot meet the requirements of fast X-ray scintillation response; Sn(Ⅱ) is easily oxidized to Sn(Ⅳ), resulting in poor stability of this type of material.

[0004] Therefore, the development of new antimony-based hybrid halides with high thermal stability and high luminescence intensity has important application prospects. Summary of the invention

[0005] The present invention provides an organic-inorganic antimony-based halide luminescent crystal, a preparation method and application thereof, aiming to develop an organic-inorganic antimony-based halide luminescent crystal with high thermal stability and high luminescence intensity.

[0006] The present invention is achieved through the following technical solutions:

[0007] An organic-inorganic antimony-based halide luminescent crystal, the chemical formula is (C 6 NH 8 )SbCl 4 .

[0008] Specifically, at room temperature, it belongs to the monoclinic system and the space group is P2 1 / c.

[0009] Specifically, the unit cell parameters are α=90°, β=106.379(2)°, γ=90°, Z=4,

[0010] A method for preparing an organic-inorganic antimony-based halide luminescent crystal comprises the following steps:

[0011] Step 1, dissolving antimony trioxide in a hydrochloric acid aqueous solution, heating and stirring for 90-100 minutes to fully react, filtering to obtain a clear solution, wherein the molar ratio of antimony trioxide to hydrochloric acid is 1:6-12;

[0012] Step 2: then add 2-methylpyridine to the clear solution of step 1, maintain the temperature of step 1 and continue stirring until a clear solution is obtained, wherein the molar ratio of 2-methylpyridine to antimony trioxide is 2-3:1;

[0013] Step 3: evaporate and crystallize the clarified solution obtained in step 2 at 25-30° C., and the obtained crystals are the organic-inorganic antimony-based halide luminescent crystals.

[0014] Specifically, the water is deionized water.

[0015] Specifically, filter while hot.

[0016] Specifically, the heating temperature is 80-100°C.

[0017] An organic-inorganic antimony-based halide luminescent crystal is used in lighting, photoelectric detection, sensing or anti-counterfeiting.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention adopts a simple volatile solvent method to prepare an organic-inorganic antimony-based halide luminescent crystal. The organic-inorganic antimony-based halide luminescent crystal is a green light fluorescent crystal. The preparation method is simple, efficient, highly repeatable, low cost, mild reaction conditions, and the prepared organic-inorganic antimony-based halide luminescent crystal has high thermal stability and high luminescence intensity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the crystal structure of the luminescent crystal of the present invention at room temperature.

[0021] Figure 2 is the X-ray powder diffraction pattern of the luminescent crystal of the present invention.

[0022] Figure 3 It is the excitation spectrum and emission spectrum of the luminescent crystal of the present invention.

[0023] Figure 4 It is a fluorescence lifetime diagram of the luminescent crystal of the present invention.

[0024] Figure 5 It is the CIE coordinate diagram of the luminescent crystal of the present invention.

[0025] Figure 6 It is a differential thermal analysis diagram of the luminescent crystal of the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0027] This embodiment provides a method for preparing an organic-inorganic antimony-based halide luminescent crystal, comprising the following steps:

[0028] Step 1, dissolving antimony trioxide in a hydrochloric acid aqueous solution, heating and stirring for 80-100 minutes to fully react, filtering to obtain a clear solution, wherein the molar ratio of antimony trioxide to hydrochloric acid is 1:6-12;

[0029] Step 2: then add 2-methylpyridine to the clear solution of step 1, maintain the temperature of step 1 and continue stirring until a clear solution is obtained, wherein the molar ratio of 2-methylpyridine to antimony trioxide is 2-3:1;

[0030] Step 3: evaporate and crystallize the clarified solution obtained in step 2 at 25-30° C., and the obtained crystals are the organic-inorganic antimony-based halide luminescent crystals.

[0031] In a specific embodiment, the water is deionized water.

[0032] In one embodiment, the filtration is performed while hot.

[0033] In one embodiment, the heating temperature is 80-100°C.

[0034] The present invention adopts a simple volatile solvent method to prepare the organic-inorganic antimony-based halide luminescent crystal of the present invention. The preparation method is simple, efficient, highly repeatable, low-cost, and has mild reaction conditions. The prepared organic-inorganic antimony-based halide luminescent crystal has high thermal stability and high luminescence intensity.

[0035] The organic-inorganic antimony-based halide luminescent crystal obtained in this embodiment has the chemical formula (C 6 NH 8 )SbCl 4 .

[0036] At room temperature, it belongs to the monoclinic system and the space group is P2 1 / c.

[0037] Specifically, the unit cell parameters are α=90°, β=106.379(2)°, γ=90°, Z=4, The Sb-Cl bond distance is Each antimony atom coordinates with 4 chlorine atoms to form [SbCl4] - Pyramidal structure. Cation 2-methylpyridine and anion [SbCl4] - They are connected by NH···Cl hydrogen bonds, where the hydrogen bond length is The discrete inorganic anions are completely separated by organic cations to form a typical zero-dimensional ionic crystal. The compound is a zero-dimensional organic-inorganic hybrid perovskite structure.

[0038] The crystal obtained in the embodiment of the present invention has an emission peak of 200-475nm under the excitation of ultraviolet light, specifically, the excitation wavelength is 315nm, and the visible light emitted is green light. The transient fluorescence spectrum test results show that the excitation wavelength of the compound is 362nm, the emission wavelength is 530nm, and the fluorescence lifetime is 1.41μs, indicating that the compound is a photoluminescent material and emits green light.

[0039] The organic-inorganic antimony-based halide luminescent crystal of the present invention has ns 2 Electronic configuration, Sb 3+ Ion 5s 2 The orbital-induced 0D structure and characteristic band structure promote the generation of self-trapped excitons (STEs), which enables ultra-broadband emission, high photoluminescence quantum yield (PLQY), long carrier lifetime, and effectively reduces the self-absorption effect.

[0040] An organic-inorganic antimony-based halide luminescent crystal is used in lighting, photoelectric detection, sensing or anti-counterfeiting.

[0041] Example 1

[0042] A preparation method of a novel organic-inorganic antimony-based halide luminescent crystal: 1.45 g of antimony trioxide is weighed, 13.24 g of hydrochloric acid with a mass fraction of 37% is added, and the mixture is heated to 90° C. and stirred to obtain a clear solution. 2.10 g of 2-methylpyridine is slowly added, and the mixture is stirred to react completely. The obtained solution is covered with a plastic wrap and pierced with several holes, and is placed in a 30° C. oven for slow evaporation and crystallization. The obtained long needle-shaped crystals are the organic-inorganic antimony-based halide luminescent crystals.

[0043] Figure 1 Organic-inorganic antimony-based halide luminescent crystal (C 6 NH 8 )SbCl 4 Schematic diagram of the structure, belonging to the monoclinic system, space group is P2 1 / c(14). The unit cell parameters are α=90°, β=106.379(2)°, γ=90°, Z=4,

[0044] The long needle-shaped crystals obtained in this example were subjected to X-ray single crystal diffraction analysis. X-ray single crystal diffraction was performed on a Rigaku XtLAB Synergy R single crystal diffractometer, Cu target, Kα radiation source (λ=1.5418nm), and the test temperature was room temperature (~293K). The structure was analyzed by Olex2. X-ray powder diffraction analysis (XRD) was performed on a Bruker D8 ADVANCE X-ray diffractometer. Figure 2 The XRD diffraction pattern of the organic-inorganic antimony-based halide luminescent crystal obtained in Example 1 is compared with the single crystal test result of the crystal, as shown in FIG. Figure 2 As shown, the obtained results are consistent with the single crystal results, which indicates that the obtained crystals have high purity.

[0045] Fluorescence excitation spectra, fluorescence emission spectra and fluorescence decay curves were performed on an FLS1000 spectrometer (Edinburgh) equipped with a continuous xenon lamp (450 W) and a microsecond lamp. Figure 3 The excitation spectrum (monitoring wavelength is 495nm and 530nm) and emission spectrum (excitation wavelength is 360nm) of the sample at room temperature respectively. The sample shows two emission peaks under ultraviolet light excitation, one emission is located in the blue-green light region (495nm), and the other emission is located in the green light region (530nm), indicating that the compound is a photoluminescent material, emitting green light. Figure 4 is the fluorescence lifetime diagram of the luminescent crystal of the present invention, such as Figure 4 As shown, the fluorescence lifetime is 1.41 μs.

[0046] Figure 5 For luminescent materials (C 6 NH 8) SbCl 4 CIE coordinate diagram. Figure 5 It can be seen that the luminescent crystal of the present invention emits green light.

[0047] The sample prepared by the present invention was placed in the air, and after one month, the luminescence intensity and spectrum did not change significantly, indicating that the sample prepared by the present invention has high chemical stability. This is because the sample has stable chemical properties and is not easy to absorb moisture.

[0048] TG tests were performed on a NETZSCH STA 449F3 instrument in dry N 2 At 10K·min -1 The heating rate is carried out. Figure 6 This is the differential thermal analysis diagram of the sample. The results show that the compound begins to decompose at 148.4°C during the heating process and has good thermal stability.

[0049] Finally, it is necessary to explain here that the above embodiments are only used to further illustrate the technical solution of the present invention in detail and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by technicians in this field based on the above content of the present invention all fall within the scope of protection of the present invention.

Claims

1. An organic-inorganic antimony-based halide luminescent crystal, characterized in that: The chemical formula is (C6NH8)SbCl4.

2. The organic-inorganic antimony-based halide luminescent crystal according to claim 1, characterized in that: At room temperature, it belongs to the monoclinic system and its space group is P21 / c.

3. The organic-inorganic antimony-based halide luminescent crystal according to claim 1, characterized in that: The unit cell parameters are α=90°, β=106.379(2)°, γ=90°, Z=4, 4. A method for preparing the organic-inorganic antimony-based halide luminescent crystal according to any one of claims 1 to 3, characterized in that: The steps include: Step 1, dissolving antimony trioxide in a hydrochloric acid aqueous solution, heating and stirring for 80-100 minutes to fully react, filtering to obtain a clear solution, wherein the molar ratio of antimony trioxide to hydrochloric acid is 1:6-12; Step 2: then add 2-methylpyridine to the clear solution of step 1, maintain the temperature of step 1 and continue stirring until a clear solution is obtained, wherein the molar ratio of 2-methylpyridine to antimony trioxide is 2-3:1; Step 3: evaporate and crystallize the clarified solution obtained in step 2 at 25-30° C., and the obtained crystals are the organic-inorganic antimony-based halide luminescent crystals.

5. The method for preparing an organic-inorganic antimony-based halide luminescent crystal according to claim 4, characterized in that: The water is deionized water.

6. The method for preparing an organic-inorganic antimony-based halide luminescent crystal according to claim 4, characterized in that: Step 1: Filter while hot.

7. The method for preparing an organic-inorganic antimony-based halide luminescent crystal according to claim 4, characterized in that: The heating temperature in step 1 is 80-100°C.

8. Use of the organic-inorganic antimony-based halide luminescent crystal according to any one of claims 1 to 3 in lighting, photoelectric detection, sensing or anti-counterfeiting.

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