Zn4(bo3)2(co2ch2nh2)2.h2o compound, crystal, preparation method and application thereof

Abstract

This invention discloses a Zn4(BO3)2(CO2CH2NH2)2·H2O compound, its crystal, preparation method, and applications. The crystal is Zn4(BO3)2(CO2CH2NH2)2·H2O crystal. The crystal of this invention has a structural configuration similar to KBBF, and its crystal structure consists of (BO3) 3‑ [Zn2BO3ON] ∞ It is composed of alternating layers of organic glycine and other compounds; [Zn2BO3ON] ∞ The [Be2BO3F2] in the layer and KBe2BO3F2 (KBBF) structure ∞ The layers are extremely similar, within which (BO3) 3‑ The nearly uniform arrangement of functional groups contributes to the main nonlinear effects of the crystal. Notably, this structure is the first to achieve [Zn₂BO₃ON] via glycine groups. ∞ Layer connectivity. This crystal has the potential for application in the ultraviolet region; at the same time, it is non-hygroscopic and possesses excellent physical properties.

Description

Technical Field

[0001] This invention belongs to the field of functional crystal materials technology, specifically relating to a Zn4(BO3)2(CO2CH2NH2)2·H2O compound, its crystal, preparation method, and application in nonlinear optics. Background Technology

[0002] Nonlinear optical (NLO) crystal materials are a class of novel optoelectronic functional materials widely used in laser technology. As core components in all-solid-state lasers, their frequency conversion capabilities allow for convenient conversion of mature laser wavelengths to other bands, enabling their widespread application in cutting-edge scientific research, laser micromachining, secure communication, information storage, laser medicine, and national defense. Currently, commercially available ultraviolet nonlinear optical crystals are mainly concentrated in borate systems, including β-BaB₂O₄ (BBO), LiB₃O₅ (LBO), CsB₃O₅ (CBO), and CsLiB₆O₄. 10 (Abbreviated as CLBO), etc. In borate systems, (BO3) 3- Planar triangular π-conjugated groups possess a wide band gap and a large microscopic second-order polarizability, making them among the most superior functional groups. Their coplanar and consistent arrangement is beneficial for constructing nonlinear optical crystals with large band gaps, frequency doubling coefficients, and birefringence. However, since B and O can also form (BO4),... 5- The presence of various functional groups, and the flexible and varied connection patterns between these groups, often makes it difficult to efficiently obtain the desired (BO3) group. 3- The structure exhibits a coplanar and uniform arrangement of functional groups. This explains why, despite the wide variety of borates, very few can simultaneously possess large band gaps, frequency doubling coefficients, and birefringence. Therefore, exploring novel ultraviolet nonlinear optical crystals with superior performance remains an extremely challenging task. Summary of the Invention

[0003] To solve the above-mentioned technical problems, the present invention provides a compound with the chemical formula Zn4(BO3)2(CO2CH2NH2)2·H2O.

[0004] The present invention also provides a method for preparing the compound with the chemical formula Zn4(BO3)2(CO2CH2NH2)2·H2O, the method comprising the following steps:

[0005] The compound was prepared by mixing a Zn-containing compound, a B-containing compound, and a glycine-containing ligand compound and carrying out a hydrothermal reaction.

[0006] According to an embodiment of the present invention, the Zn-containing compound is selected from at least one of ZnO, Zn(OH)2, and ZnC4H8N2O4, preferably Zn(OH)2.

[0007] According to an embodiment of the present invention, the B-containing compound is selected from at least one of H3BO3, B2O3, and HBO2, preferably H3BO3.

[0008] According to an embodiment of the present invention, the glycine-containing ligand compound is selected from one of C3H4N2O2, C2H5NO2, and C2H7ClNO2, preferably C2H5NO2.

[0009] According to embodiments of the present invention, the molar ratio of the Zn-containing compound, the B-containing compound, and the glycine-containing ligand compound is (1-3):(1-3):1; preferably (1-2):(1-2):1; exemplaryly, it is 1:2:1. For example, the molar ratio of Zn(OH)2:H3BO3:C2H5NO2 is (1-3):(1-3):1.

[0010] According to an embodiment of the present invention, the hydrothermal reaction is carried out in a solvent, which may be selected from water or a mixed solvent of water and CF3COOH, for example, the volume ratio of water to CF3COOH is (3-20):1.

[0011] The preferred solvent is a mixture of 5-9 ml of water and 0.5-1.5 ml of CF3COOH, for example, 9 ml of deionized water and 0.5 ml of CF3COOH.

[0012] According to an embodiment of the present invention, the reaction temperature of the hydrothermal reaction can be 160–200°C, preferably 180–200°C, for example, 180°C. Further, the heating rate of the hydrothermal reaction can be 10–30°C / h, exemplarily 10°C / h, 20°C / h, or 30°C / h.

[0013] According to an embodiment of the present invention, the reaction time of the hydrothermal reaction can be 1 to 5 days, preferably 2 to 4 days, and exemplarily 2, 3, or 4 days.

[0014] According to an embodiment of the present invention, the method further includes cooling the hydrothermal reaction products.

[0015] Preferably, after the reaction is completed, the temperature is reduced to room temperature at a rate of 1–10 °C / h.

[0016] The present invention also provides a nonlinear optical crystal with the chemical formula Zn4(BO3)2(CO2CH2NH2)2·H2O, that is, the nonlinear optical crystal is Zn4(BO3)2(CO2CH2NH2)2·H2O crystal.

[0017] According to an embodiment of the present invention, the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal belongs to the trigonal crystal system, with space group P3221 and cell parameters of [missing information]. α=β=90°, γ=120°, z=6.

[0018] According to an embodiment of the present invention, the nonlinear optical crystal has substantially the following characteristics: Figure 2 The X-ray diffraction pattern shown.

[0019] According to an embodiment of the present invention, the powder frequency doubling effect of the nonlinear optical crystal is approximately 0.85 times that of KH2PO4 (KDP).

[0020] According to an embodiment of the present invention, the ultraviolet absorption edge of the nonlinear optical crystal can reach 201 nm, the band gap of the crystal is as wide as 6.17 eV, and high transmittance can be achieved between 240 and 1400 nm. That is, the nonlinear optical crystal is an ultraviolet optical crystal.

[0021] According to an embodiment of the present invention, the nonlinear optical crystal structure is composed of a honeycomb-shaped [Zn₂BO₃ON] crystal. ∞ It is composed of alternating layers of organic glycine and other organic layers.

[0022] The present invention also provides a method for preparing the nonlinear optical crystal, wherein the method comprises: mixing a Zn-containing compound, a B-containing compound, a glycine-containing ligand compound and a solvent, and then heating and crystallizing to obtain the crystal.

[0023] Preferably, the selection of the Zn-containing compound, the B-containing compound, the glycine-containing ligand compound, and the solvent is consistent with the selection in the preparation method of the compound with the chemical formula Zn4(BO3)2(CO2CH2NH2)2·H2O.

[0024] According to an embodiment of the present invention, the temperature for the heating crystallization is 160–200°C;

[0025] The heating and crystallization time is 3 to 10 days, preferably 3 to 7 days, and exemplarily 5, 6, or 7 days.

[0026] Preferably, the preparation method further includes: after crystallization is completed, cooling, separating, and drying the reaction solution to obtain the crystal.

[0027] Preferably, during the cooling process, the cooling rate is 1 to 10°C / h, with examples being 1°C / h, 5°C / h, and 9°C / h.

[0028] According to an embodiment of the present invention, the method for preparing the crystal specifically includes the following steps:

[0029] (a) A Zn-containing compound, a B-containing compound, a glycine-containing ligand compound, and a solvent are mixed in a certain proportion, and the mixture is heated to 160–200°C at a rate of 10–30°C / hour, and then crystallized at this temperature for 3–10 days.

[0030] (b) After crystallization, the reaction system is cooled to room temperature at a rate of 1 to 10 °C / h, and the crystals are obtained after separation and drying.

[0031] The present invention also provides the above-mentioned crystal in the fields of laser frequency doubling, electro-optic modulation, photorefractive information processing and storage, catalysis, etc.; preferably, it is used as a frequency doubling device in all-solid-state lasers.

[0032] The beneficial effects of this invention are:

[0033] The inventors discovered that in borate systems, π-conjugated (BO3) 3- Planar triangular groups possess a wide band gap and a large microscopic second-order polarizability. Their coplanar and consistent arrangement is beneficial for synthesizing nonlinear optical crystals with both large band gaps and frequency doubling coefficients. (BO3) 3- The KBBF group is considered the most outstanding nonlinear optically active group among borates, with the most representative crystal being KBBF2BO3F2 (KBBF). The KBBF structure is a typical layered structure, and the weak interlayer forces are the root cause of its severe layered growth habit. Structural modification based on the KBBF structure, including enhancing interlayer forces, is a hot topic in the creation of novel nonlinear optical crystals. This invention creatively uses glycine as a linking group to construct an organic-inorganic hybrid ultraviolet nonlinear optical crystal with KBBF structural characteristics.

[0034] (1) This invention provides a novel glycine-boric acid composite Zn4(BO3)2(CO2CH2NH2)2·H2O compound and its crystal, which has a structural configuration similar to KBBF, and its crystal structure consists of (BO3) 3- [Zn2BO3ON] ∞ It is composed of alternating layers of organic glycine and other compounds; [Zn2BO3ON] ∞ The [Be2BO3F2] in the layer and KBe2BO3F2 (KBBF) structure ∞ The layers are extremely similar, within which (BO3) 3- The nearly uniform arrangement of functional groups contributes to the main nonlinear effects of the crystal. Notably, this structure is the first to achieve [Zn₂BO₃ON] via glycine groups. ∞ Layer connectivity. This crystal has the potential for application in the ultraviolet region; at the same time, it is non-hygroscopic and possesses excellent physical properties.

[0035] (2) The Zn4(BO3)2(CO2CH2NH2)2·H2O crystal of the present invention outputs strong 532nm light (i.e., second harmonic) under 1064nm laser irradiation. Its powder frequency doubling effect is about 0.85 times that of KH2PO4(KDP), and it can achieve phase matching.

[0036] (3) The Zn4(BO3)2(CO2CH2NH2)2·H2O crystal of the present invention has a wide light transmission range, with high transmittance between 240-1400nm, an ultraviolet cutoff edge of up to 201nm, and a band gap as wide as 6.17eV. It can be applied in the ultraviolet region and has potential application prospects in nonlinear optics, laser technology, electro-optic modulation, photorefractive information processing and information storage, catalysis and other fields.

[0037] (4) The Zn4(BO3)2(CO2CH2NH2)2·H2O crystal of the present invention has stable physicochemical properties.

[0038] (5) The preparation method of the Zn4(BO3)2(CO2CH2NH2)2·H2O compound and crystal of the present invention is simple, fast, and low in cost. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the crystal structure of Zn4(BO3)2(CO2CH2NH2)2·H2O crystal of the present invention.

[0040] Figure 2 The image shows a comparison between the simulated X-ray diffraction pattern of the sample in Example 2 obtained by fitting the crystal structure obtained from the single-crystal X-ray diffraction data and the powder X-ray diffraction pattern of the sample obtained in Example 2.

[0041] Figure 3 The image shows the ultraviolet-visible-near-infrared transmission spectrum of the sample from Example 2.

[0042] Figure 4 This is a schematic diagram of a frequency doubling test, where 1 is a laser, 2 is the incident laser beam, 3 is the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal of Example 2, 4 is the generated outgoing laser beam, and 5 is a photomultiplier tube equipped with a filter.

[0043] Figure 5 The results of frequency doubling tests are for the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal sample in Example 2. Detailed Implementation

[0044] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0045] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0046] Example 1: Preparation of the compound Zn4(BO3)2(CO2CH2NH2)2·H2O

[0047] Zn4(BO3)2(CO2CH2NH2)2·H2O crystals were prepared by the following steps:

[0048] (a) Zn(OH)2 (0.005mol, 0.497g), H3BO3 (0.01mol, 0.618g), C2H5NO2 (0.005mol, 0.375g), H2O (9ml) and CF3COOH (0.5ml) were placed in a reaction vessel with a polytetrafluoroethylene liner, and the temperature was increased to 180℃ at a rate of 20℃ / hour and held at that temperature for 2 days.

[0049] (b) After the reaction is complete, the system is cooled to room temperature at a rate of 5℃ / h. After separation and drying, the compound Zn4(BO3)2(CO2CH2NH2)2·H2O can be obtained.

[0050] Example 2: Preparation of Zn4(BO3)2(CO2CH2NH2)2·H2O crystals

[0051] Zn4(BO3)2(CO2CH2NH2)2·H2O crystals were prepared by the following steps:

[0052] (a) Zn(OH)2 (0.005mol, 0.497g), H3BO3 (0.01mol, 0.618g), C2H7ClNO2 (0.005mol, 0.552g), H2O (9ml) and CF3COOH (0.5ml) were placed in a reaction vessel with a polytetrafluoroethylene liner, and the temperature was increased to 180℃ at a rate of 15℃ / hour, and crystallized at this temperature for 5 days.

[0053] (b) After crystallization, the reaction system is cooled to room temperature at a rate of 5℃ / h. After separation and drying, Zn4(BO3)2(CO2CH2NH2)2·H2O crystals can be obtained.

[0054] Example 3: Preparation of Zn4(BO3)2(CO2CH2NH2)2·H2O crystals

[0055] Zn4(BO3)2(CO2CH2NH2)2·H2O crystals were prepared by the following steps:

[0056] (a) Zn(OH)2 (0.005mol, 0.497g), H3BO3 (0.01mol, 0.618g), C3H4N2O2 (0.005mol, 0.5g), H2O (5ml) and CF3COOH (1ml) were placed in a reaction vessel with a polytetrafluoroethylene liner, and the temperature was increased to 180℃ at a rate of 20℃ / hour and crystallized at a constant temperature for 5 days;

[0057] (b) After crystallization, the reaction system is cooled to room temperature at a rate of 5℃ / h. After separation and drying, Zn4(BO3)2(CO2CH2NH2)2·H2O crystals can be obtained.

[0058] Structural analysis of Zn4(BO3)2(CO2CH2NH2)2·H2O crystal in Example 4

[0059] The structures of the Zn₄(BO₃)₂(CO₂CH₂NH₂)₂·H₂O crystal samples prepared in Examples 2 and 3 were analyzed using single-crystal X-ray diffraction and powder X-ray diffraction. Single-crystal X-ray diffraction was performed using a Rigaku XtaLAB Pro MM003Cu / Mo single-crystal X-ray diffractometer. The data collection temperature was 288.9 K, and the diffraction source was Cu-Kα rays (…). The scanning mode was ω = 2θ, and the data underwent absorption correction processing using the Multi-Scan method. Structural analysis was performed using the SHELXTL package; the positions of heavy atoms were determined using a direct method, and the coordinates of the remaining atoms were obtained using the difference Fourier synthesis method; F-based... 2 The coordinates and anisotropic thermal parameters of all atoms were refined using the full matrix least squares method. Single-crystal X-ray diffraction results showed that the chemical formula of the samples in Examples 2 and 3 was Zn₄(BO₃)₂(CO₂CH₂NH₂)₂·H₂O, belonging to the trigonal crystal system with space group P3221 and cell parameters of [missing information]. α = β = 90°, γ = 120°, z = 6. A schematic diagram of the crystal structure is shown below. Figure 1 As shown.

[0060] Powder X-ray diffraction (XRD) data were acquired using a Rigaku SmartLab 9kW diffractometer. The test conditions were a fixed target, a monochromatic Cu-Kα light source, and a wavelength of [wavelength missing]. The scanning range was 5–70°, with a scanning step size of 0.02°. Powder X-ray diffraction patterns showed that the diffraction peak positions of the samples in Examples 1–3 were essentially the same. Taking the sample of Example 2 as a typical example, its powder X-ray diffraction pattern results are as follows: Figure 2 As shown in the figure, the X-ray diffraction pattern obtained by fitting the crystal structure obtained from the single-crystal X-ray diffraction analysis is basically consistent with the peak position and peak intensity of the powder X-ray diffraction pattern of the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal sample prepared in Example 2.

[0061] Example 5: Frequency doubling test experiment of Zn4(BO3)2(CO2CH2NH2)2·H2O crystal

[0062] A frequency doubling test was performed on the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal sample prepared in Example 2. A 1064nm laser emitted from an Nd:YAG solid-state laser was used as the fundamental frequency light to irradiate the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal powder prepared in Example 2. The generated frequency doubling light was detected using a photomultiplier tube, and the harmonic intensity was displayed using an oscilloscope. The specific method is as follows:

[0063] The particle size distribution of the crystal samples to be tested was determined using standard sieves to be 45–60 μm, 60–70 μm, 70–100 μm, 100–150 μm, 150–200 μm, 200–250 μm, 250–325 μm, and 325–500 μm. The crystal samples of these particle sizes were then placed... Figure 4 At position 3 of the apparatus shown, at room temperature, a Q-switched Nd:YAG laser (i.e., laser 1) is used as the input light source. The incident wavelength of the laser beam 2 is 1064 nm. After the incident laser beam 2 passes through crystal 3 of Example 2, the frequency harmonic signal of the output laser beam 4 after passing through filter 5 is measured, and the trend of the frequency harmonic signal with particle size is observed to determine whether phase matching can be achieved. Under the same test conditions, KH2PO4 (KDP) is used as the reference for the second harmonic test. The test results are as follows. Figure 5 As shown, Figure 5 The results show that the powder frequency doubling effect of Zn4(BO3)2(CO2CH2NH2)2·H2O crystal under 1064nm laser irradiation is about 0.85 times that of KDP under the same conditions, and phase matching can be achieved.

[0064] Example 6: Spectral performance test of Zn4(BO3)2(CO2CH2NH2)2·H2O crystal

[0065] The ultraviolet to near-infrared spectral performance of the Zn4(BO3)2(CO2CH2NH2)2·H2O crystal sample prepared in Example 2 was tested.

[0066] Ultraviolet-visible-near-infrared transmission spectroscopy was performed using a Hitachi UV-Vis-NIR spectrophotometer (Japan). The test results are as follows: Figure 3 As shown, Figure 3 The results show that Zn4(BO3)2(CO2CH2NH2)2·H2O crystal has a wide transmission range, with high transmittance in the 240-1400nm spectral range and an ultraviolet absorption cutoff wavelength of 201nm. Through conversion, its band gap can be determined to be 6.17eV.

[0067] The embodiments of the present invention have been described above by way of example. However, the scope of protection of the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A nonlinear optical crystal, characterized by, The chemical formula of the crystal is Zn4(BO3)2(CO2CH2NH2)2·H2O, that is, the nonlinear optical crystal is Zn4(BO3)2(CO2CH2NH2)2·H2O crystal. The Zn4(BO3)2(CO2CH2NH2)2·H2O crystal belongs to a trigonal system, a space group is P3221, a unit cell parameter is a=9.8916 Å, b=9.8916 Å, c=24.3625 Å, α=β=90 o , γ=120 o , z=6.

2. The crystal of claim 1, wherein Zn4(BO3)2(CO2CH2NH2)2 The H2O crystal structure is formed by a honeycomb-like [Zn2BO3ON] The layers are alternately stacked with the glycine organic layers.

3. A method for the preparation of the crystal according to claim 1 or 2, characterized in that, The method is: mixing Zn-containing compound, B-containing compound, glycine ligand-containing compound and solvent, heating and crystallizing to obtain the crystal.

4. The method of claim 3, wherein, The temperature of the heating and crystallizing is 160-200 DEG C. The time of the heating and crystallizing is 3-10 days.

5. The crystal of claim 1 or 2 is applied in the fields of laser frequency doubling, electro-optic modulation, photorefractive information processing and information storage or catalysis.

6. Use according to claim 5, characterized in that, In frequency doubling devices used in all-solid-state lasers.

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