Low-dimensional organic-inorganic hybrid halide materials for fluorescent probes for nitrobenzene with high moisture stability and high quantum yield fluorescence

Abstract

The invention discloses a fluorescent probe low-dimensional organic-inorganic hybrid halide material with high humidity stability and high quantum yield fluorescence for nitrobenzene, and relates to the technical field of material synthesis, the key point of the technical scheme is as follows: the halide material is synthesized by adopting a hydrochloric acid solution of SbCl3 and MPP through a rapid evaporation technology to obtain a white [MPP] 2SbCl7. 2H2O crystal, and the [MPP] 2SbCl7. 2H2O crystal is used for preparing the fluorescent probe low-dimensional organic-inorganic hybrid halide material with high humidity stability and high quantum yield fluorescence. The space group of the crystal is C2 / c, and the crystal structure is characterized in that isolated SbCl6 octahedrons and an MPP ring form a 0D structure. The [MPP] 2SbCl7. 2H2O synthesized by the invention has strong moisture stability, high PLQY and high exciton binding energy, shows a huge prospect in applications requiring stable photoelectrons in moisture, in addition, the [MPP] 2SbCl7. 2H2O also shows a reversible fluorescent switch reaction on nitrobenzene, has excellent repeatability and selectivity, deepens understanding of 0D hybrid antimony halide, and has good application prospects. Moreover, a foundation is laid for application of the compound in various photoelectric and sensing devices, and a new way is opened up for research of luminescent materials and detection application.

Description

Technical Field

[0001] The invention relates to the technical field of material synthesis, and more particularly to a low-dimensional organic-inorganic hybrid halide material as a fluorescent probe for nitrobenzene with high moisture stability and high quantum yield fluorescence. Background Art

[0002] In recent years, organic-inorganic hybrid halides have attracted great attention due to their excellent optical and electronic properties and their outstanding performance in various optoelectronic applications. Due to the diversity of organic cations and the geometric structures of anionic metal halides, the unique structural tunability of the materials allows various connections between metal halides, from three-dimensional (3D) networks to two-dimensional (2D) layers, to one-dimensional (1D) chains or zero-dimensional (0D) structures, among which low-dimensional metal halides exhibit unique photophysical properties due to strong quantum confinement effects. According to the mechanism proposed by Hemamala, the dimensionality of the crystal structure affects the self-trapped excitons (STEs) caused by the soft lattice and exciton-phonon interactions. In low-dimensional metal halides, the metal polyhedra are separated by the surrounding organic or inorganic ions, resulting in strong exciton recombination and efficient self-trapped exciton emission. The intrinsic problem of the instability of lead halide perovskites still hinders the practical application of lead halide perovskites.

[0003] Novel low-dimensional lead-free metal halides have been investigated as potential alternatives to lead halide perovskites for light emission applications due to their superior optical properties such as high photoluminescence quantum yield (PLQY), tunable optical band gap, and large Stokes shift. Therefore, the luminescence properties of low-dimensional metal halides have attracted much attention. Their versatility allows customized combinations, bringing promise for applications such as light sensors, light-emitting diodes (LEDs), and scintillators. However, their poor water stability hinders their use, especially in humid environments. Effective lighting materials require moisture resistance and high fluorescence efficiency. To address this challenge, novel halides are needed to improve their moisture stability without sacrificing their luminescence properties. In the field of optoelectronic applications, it remains crucial to seek moisture-stable low-dimensional hybrid halides emitting blue light.

[0004] Although progress has been made in synthesizing yellow-orange light-emitting zero-dimensional lead-free halides, the pursuit of truly moisture-stable candidate halides continues. Therefore, the present invention aims to provide a low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence. The present invention synthesizes a new type of organic-inorganic hybrid semiconductor [MPP]2SbCl7·2H2O, which has yellow-orange light emission under ultraviolet excitation, and has strong moisture stability, high PLQY and high exciton binding energy, showing great prospects in applications requiring stable photoelectrons in moisture. In addition, [MPP]2SbCl7·2H2O exhibits a reversible fluorescence switching reaction to nitrobenzene, showing its potential as an organic pollutant sensing platform with excellent repeatability and selectivity. The present invention not only deepens the understanding of 0D hybrid antimony halides, but also lays a foundation for their application in various optoelectronic and sensor devices, and opens up a new path for the research of luminescent materials and detection applications.

[0006] The above technical purpose of the present invention is achieved through the following technical scheme: a low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence, wherein the chemical formula of the halide material is: [MPP]2SbCl722H2O.

[0007] The present invention is further configured as follows: the halide material is synthesized by using a hydrochloric acid solution of SbCl3 and MPP through a rapid evaporation technology to obtain a white [MPP]2SbCl7·2H2O crystal.

[0008] The present invention is further configured as follows: the MPP is protonated 1-(3-methoxyphenyl)piperazine.

[0009] The present invention is further configured as follows: the space group of the crystal is C2 / c, and the space group is determined by single crystal X-ray diffraction.

[0010] The present invention is further configured as follows: the unit cell parameters of the crystal are:

[0011]

[0012]

[0013] The present invention is further configured as follows: the crystal structure is characterized in that isolated SbCl6 octahedra and MPP rings form a 0D structure.

[0014] The invention also provides the application of a low-dimensional organic-inorganic hybrid halide material as a fluorescent probe for nitrobenzene with high moisture stability and high quantum yield fluorescence in optoelectronic and sensor devices.

[0015] In summary, the present invention has the following beneficial effects:

[0016] 1. The present invention selects MPP (MPP = protonated 1-(3-methoxyphenyl) piperazine) as the cation, because it has good hydrophobicity, so that the stability and moisture resistance of the hybrid halide material obtained by the present invention can be enhanced;

[0017] 2. The present invention synthesizes a new type of organic-inorganic hybrid semiconductor MPP]2SbCl7·2H2O, which has yellow-orange light emission under ultraviolet excitation. At the same time, it has strong moisture stability, high PLQY and high exciton binding energy, and shows great prospects in applications that require stable photoelectronics in moisture;

[0018] 3. The [MPP]2SbCl7·2H2O synthesized in the present invention exhibits a reversible fluorescence switching reaction to nitrobenzene, showing its potential as a sensing platform for organic pollutants with excellent repeatability and selectivity. At the same time, the present invention not only deepens the understanding of 0D hybrid antimony halides, but also lays the foundation for their application in various optoelectronic and sensor devices, opening up a new path for the research of luminescent materials and detection applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 2H2O; (a) comparison between theoretical and experimental values ​​of PXRD of [MPP]2SbCl7·2H2O; (b) excitation and emission spectra of [MPP]2SbCl7·2H2O; (c) color coordinates of [MPP]2SbCl7·2H2O; (d) quantum yield of [MPP]2SbCl7·2H2O; (e) variable temperature PL of [MPP]2SbCl7·2H2O; (f) Ea value of [MPP]2SbCl7·2H2O);

[0020] Figure 2 2H2O in the present invention ((a) fluorescence spectra of [MPP]2SbCl7·2H2O placed in humid air for different days; (b) comparison of [MPP]2SbCl7·2H2O PXRD theoretical value and experimental value after 60 days of placement in humid air);

[0021] Figure 3 This is a relationship diagram of the experimental data of the [MPP]2SbCl7·2H2O fluorescent probe in an embodiment of the present invention ((a) PL emission spectrum of [MPP]2SbCl7·2H2O after adding different types of organic solvents; (b) PXRD changes of [MPP]2SbCl7·2H2O after adding different types of organic solvents; PL emission spectrum (c) and optical image (d) of [MPP]2SbCl7·2H2O after being placed in different cycles). DETAILED DESCRIPTION

[0022] The following is combined with Figure 1-3 The present invention is described in further detail.

[0023] Embodiment: A low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence, wherein the chemical formula of the halide material is: [MPP]2SbCl7·2H2O; the halide material is specifically synthesized by using a hydrochloric acid solution of SbCl3 and MPP (MPP = protonated 1-(3-methoxyphenyl)piperazine) through a rapid evaporation technique to obtain a white [MPP]2SbCl7·2H2O crystal, and its specific chemical formula is [C 11 H 18 N2O]2SbCl7·2H2O, the crystal structure is determined by single crystal X-ray diffraction, the space group of the crystal is C2 / c, and the specific unit cell parameters of the crystal are obtained as follows: The crystal structure of [MPP]2SbCl7·2H2O is characterized by isolated SbCl6 octahedra and MPP rings forming a 0D structure.

[0024] In the [MPP]2SbCl7·2H2O of this embodiment, the organic cation [MPP] 2+ Balanced [SbCl6] 3- The negative charge of anions, such as Figure 1 As shown in (a), the powder X-ray diffraction pattern (PXRD pattern) is very close to the simulated data based on the single crystal structure and can be used to confirm the purity of the [MPP]2SbCl7·2H2O powder.

[0025] The [MPP]2SbCl722H2O of this embodiment emits yellow-orange light under ultraviolet light with a wavelength of 365 nm. In addition, a prominent peak is observed at 612 nm, accompanied by a large Stokes shift and a full width at half maximum (FWHM) of 156 nm, as shown in FIG. Figure 1 (b). In addition, according to the photoluminescence (PL) emission spectrum of [MPP]2SbCl7·2H2O, the CIE color coordinates are calculated to be (0.52, 0.45) ( Figure 1 (c)); In addition, the compound [MPP]2SbCl7·2H2O has a strong yellow-orange light emission, and the measured photoluminescence quantum yield (PLQY) percentage is 60.86%, such as Figure 1(d) To verify that the broadband light does not originate from surface defects, for [MPP]2SbCl7·2H2O, the fluorescence spectra of microscale powder and bulk crystal are compared in this example. The microscale powder spectrum has a similar spectral profile to the emission spectrum of the bulk crystal and a slightly lower intensity than the emission spectrum of the bulk crystal, which excludes the possibility of surface defect-related emission.

[0026] During the cooling process, all emission intensities of yellow-orange light emitted by [MPP]2SbCl7·2H2O increase monotonically, which is due to the decrease of nonradiative recombination rate. In addition, various photoluminescence emission spectra were studied in the temperature range of 80 to 300 K. Figure 1 (e)), the relationship between temperature and radiation intensity can be simulated by the Arrhenius model:

[0027]

[0028] Among them, I0 and I PL represents the intensity-integrated emission intensity at 0K and at different temperatures, E a represents the exciton energy, k B is the Boltzmann constant, T is the thermodynamic temperature, and A is the pre-exponential factor.

[0029] Provides an exciton binding energy of 135.88 meV ( Figure 1 (f)), these values ​​are much larger than those of conventional 3D CsPbX3 perovskites (~50 meV). In addition, the larger exciton binding energy is conducive to strong radiative recombination.

[0030] To evaluate its stability, [MPP]2SbCl7·2H2O crystals were placed in a humid environment (under atmospheric conditions with humidity exceeding 90%) for more than two months. Under 365nm UV irradiation, [MPP]2SbCl7·2H2O showed stable yellow-orange visible light emission, with no obvious decay even for a long time ( Figure 2 (a)); Figure 2 As shown in (b), the PXRD pattern of [MPP]2SbCl7·2H2O further confirms its luminescence and structural stability in a humid environment.

[0031] The unique and versatile properties of the crystal structure of this 0D halide framework were also explored in this example to reveal its potential as a fluorescent switch triggered by small chemical molecules, for example as an effective fluorescent probe. The PL emission of the microcrystals was monitored before and after the addition of benzene and its derivatives to the microcrystals to evaluate the sensing ability of MPP]2SbCl7·2H2O. 4 ml of aromatic hydrocarbon derivatives were used as sensing targets, namely toluene (C6H5CH3), chlorobenzene (C6H5Cl), bromobenzene (C6H5Br), iodobenzene (C6H5I), ethylbenzene (C6H5C2H5), benzene (C6H6) and nitrobenzene (C6H5NO2). Figure 3 As shown in (a), the PL emission spectrum shows that the emission intensity drops sharply to 0.56% due to the quenching effect of C6H5NO2, while there is no obvious change compared with other solvents. Figure 3 As shown in (b), the PXRD did not change. Importantly, after the fluorescence of [MPP]2SbCl7·2H2O microcrystals induced by C6H5NO2 weakened, it could be completely restored after washing with toluene, and the restored fluorescence intensity was close to the initial value (e.g. Figure 3 (c)). This convincingly demonstrates the reversible PL switching ability of [MPP]2SbCl7·2H2O to C6H5NO2. In this example, in order to confirm the consistency of this reversible quenching-recovery process, the changes in the PL emission intensity of [MPP]2SbCl7·2H2O microcrystals were monitored during the immersion-washing cycle. The fluorescence spectrum of the microcrystals depicts a consistent quenching and recovery cycle, with the emission intensity being the minimum after 3 cycles, showing excellent repeatability and reversibility (as shown in Figure 2). Figure 3 (d)). After [MPP]2SbCl7·2H2O was exposed to C6H5NO2, a reversible fluorescence quenching phenomenon occurred. This is because the electron-deficient nitrobenzene molecules adsorbed on the surface of [MPP]2SbCl7·2H2O were removed from [SbCl6] 3- Charge transfer to the surface of [MPP]2SbCl7·2H2O. These findings highlight the potential of [MPP]2SbCl7·2H2O microcrystals as an effective fluorescent probe for the detection of C6H5NO2 with high reproducibility, selectivity, and sensitivity, marking the development of a new antimony halide fluorescent probe for the detection of C6H5NO2, thus advancing the detection applications based on metal halide luminescent materials.

[0032] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A low-dimensional organic-inorganic hybrid halide material as a fluorescent probe for nitrobenzene with high moisture stability and high quantum yield fluorescence, characterized by: The chemical formula of the halide material is: [MPP] 2SbCl 7 · 2H 2 O.

2. The low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence according to claim 1, characterized in that: The halide material is synthesized by using a hydrochloric acid solution of SbCl3 and MPP through a rapid evaporation technology to obtain a white [MPP]2SbCl7·2H2O crystal.

3. The low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence according to claim 2, characterized in that: The MPP is protonated 1-(3-methoxyphenyl)piperazine.

4. The low-dimensional organic-inorganic hybrid halide material as a fluorescent probe for nitrobenzene with high moisture stability and high quantum yield fluorescence according to claim 2, characterized in that: The space group of the crystal is C2 / c, which is determined by single crystal X-ray diffraction.

5. The low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence according to claim 2, characterized in that: The unit cell parameters of the crystal are:

6. The low-dimensional organic-inorganic hybrid halide material for a fluorescent probe of nitrobenzene with high moisture stability and high quantum yield fluorescence according to claim 2, characterized in that: The crystal structure is characterized by isolated SbCl6 octahedra and MPP rings forming a 0D structure.

7. Fluorescent probe for nitrobenzene with high moisture stability and high quantum yield fluorescence. Application of low-dimensional organic-inorganic hybrid halide materials in optoelectronic and sensor devices.

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