Inorganic-organic hybrid carbonyl radical luminescent material as well as preparation method and application thereof

Abstract

The invention discloses an inorganic-organic hybrid carbonyl radical luminescent material as well as a preparation method and application thereof, and belongs to the technical field of luminescent materials. The inorganic-organic hybrid carbonyl free radical luminescent material provided by the invention is commonly characterized in that tricarbonyl substituted benzene derivative molecules subjected to weak coordination with metal are taken as an object, a series of imidazolium salt ionic liquid molecules are taken as a subject, and a supramolecular assembly is formed in a subject-object doping manner; stable luminescence of carbonyl free radicals is protected by electrostatic interaction and electron delocalization effect generated in the system; metal ions coordinated with free radical molecules in the assembly regulate and control the photophysical properties of the inorganic-organic hybrid carbonyl free radical luminescent material through charge transfer. Through the synergistic effect of the three components, the inorganic-organic hybrid carbonyl free radical luminescent material has the characteristic of adjustable luminescent color, and dual-mode detection of Cd3 + (turn off type) and Pb3 + (turn on type) is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of luminescent materials, and in particular relates to an inorganic-organic hybrid carbonyl free radical luminescent material and a preparation method and application thereof. Background Art

[0002] Organic free radicals have good application prospects in organic light-emitting devices, spin probes, electron-hole transport and magnetic materials due to their unique open-shell structure and excellent optical, electronic and magnetic properties. Organic free radical luminescent materials with unique dual-state luminescence properties have gradually become a research hotspot. Generally, they have unusual photophysical properties such as long-wave emission, stimulus-responsive emission and high electroluminescence quantum efficiency. However, most free radicals are short-lived because they are incredibly reactive due to unpaired electrons. They are also easily structurally destroyed through dimerization, hydrogen abstraction and other chemical reactions. Therefore, most free radicals usually show weak or no luminescence under ambient conditions due to rapid quenching in the environment. Therefore, the types of organic luminescent free radicals under ambient conditions are still scarce. Only a few free radicals have been reported to emit light stably at room temperature, such as triarylmethyl radical derivatives, carbonyl radicals, imidazole radicals and triphenylamine radicals. But these free radicals usually have relatively low luminescence efficiency. Therefore, it is urgent to develop new strategies to promote the release of free radicals.

[0003] At present, the methods for stabilizing organic free radicals include steric protection, host-guest interaction, polymer environment, etc. Among them, stabilizing organic free radicals by steric protection or spin delocalization effect is a practical and widely used method. However, the complex synthesis steps greatly increase the cost and hinder its practical application. In contrast, materials that protect organic free radicals through supramolecular interactions are usually inexpensive and readily available. However, most of the supramolecular methods currently used to protect emitting free radicals are based only on hydrogen bonds, π-π, CH-π interactions, etc. These methods can limit the exciton motion of free radicals, but cannot regulate the spin delocalization of free radicals, let alone accurately regulate the luminescent properties of free radicals. Therefore, it is of great significance to develop new methods that combine molecular motion constraints and regulation of spin delocalization, and on this basis, to obtain free radical luminescent materials with dynamic luminescence changes and multiple light stimulus responses. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention provides an inorganic-organic hybrid carbonyl free radical luminescent material and a preparation method and application thereof, which solves the problem of low stability efficiency of the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: to provide an inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (I):

[0006] (I), Where R is H or CH 3 , M is a transition metal ion, and X is an inorganic acid radical.

[0007] The beneficial effect of the present invention is as follows: the present invention provides an organic-inorganic hybrid free radical luminescent material with a tricarbonyl substituted benzene derivative as a free radical central molecule, which is weakly coordinated with an inorganic metal salt. The material has good charge transfer ability and exhibits good EPR signal intensity in an EPR test. Combined with the fact that after being activated by ultraviolet light, it can remain unextinguished and return to the ground state for a long time in a natural state. Therefore, the above-mentioned organic-inorganic hybrid free radical luminescent material has good free radical stability.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, M is Mn 2+ 、Co 2+ , Fe 3+ or Ni 2+ .

[0010] Furthermore, X is SO 4 2- or NO 3 - .

[0011] Furthermore, the luminescent material is one of the compounds represented by formula (a) to formula (h):

[0012] (a)

[0013] (b)

[0014] (c)

[0015] (d)

[0016] (e)

[0017] (f)

[0018] (g) or

[0019] (h).

[0020] The beneficial effect of adopting the further technical solution is that after the metal is coordinated, there is a violent charge transfer between the organic free radical molecules and the metal ions, as well as a weak interaction within the scope of van der Waals force, so that the organic-inorganic free radical emission system of the present invention has multiple excited states and emission states, thereby obtaining multiple stimulus response properties, and the organic-inorganic free radical emission system of the present invention can form a bridging effect with other metals, thereby changing the emission intensity, and thus can detect a variety of heavy metal ions with high sensitivity.

[0021] The present invention also provides a method for preparing an inorganic-organic hybrid carbonyl free radical luminescent material, comprising the following steps: S1: preparing an acetone solution of tricarbonyl-substituted benzene organic small molecule as solution 1, preparing an acetone solution of imidazole salt ionic liquid as solution 2, and preparing a mixed solution of water and THF of inorganic metal salt as solution 3; S2: Solution 1 and solution 3 were mixed in a volume ratio of 5:1, heated to 126°C and refluxed for 6 h. After the reaction was completed, the mixture was cooled to room temperature, purified by column chromatography, and vacuum dried at 60°C to constant weight to obtain an intermediate product. S3: dissolving the intermediate product in a mixture of water, DMF and THF to obtain solution 4; S4: Solution 2 and solution 4 are mixed in a volume ratio of 50:1, and then ultrasonicated for 30-40 minutes. After the ultrasonication, the mixed solution is dried at 70°C until the sample is in a fluid state, thereby obtaining an inorganic-organic hybrid carbonyl radical luminescent material.

[0022] The beneficial effects of the present invention are as follows: the preparation method provided by the present invention enables the tricarbonyl substituted benzene derivative molecules to form a weak coordination effect with the metal ions in the inorganic metal salt through the aforementioned reaction, and then uses it as a guest to perform supramolecular self-assembly in the ionic environment of the main molecule imidazolium salt ionic liquid molecule, thereby protecting the luminescence of the carbonyl free radical through electrostatic action and electron delocalization effect, and finally obtaining an inorganic-organic hybrid carbonyl free radical luminescent material; the method is simple in steps and avoids the problems of complex synthesis route and low stabilization efficiency when stabilizing free radical emission using traditional methods such as steric hindrance effect or polymer engineering.

[0023] Furthermore, the tricarbonyl-substituted benzene organic small molecule is 1,3,5-triacetylbenzene or 1,3,5-trialdehydebenzene, and the molar concentration of solution 1 is 5×10 -3 mol / L.

[0024] Furthermore, the imidazolium salt ionic liquid is shown in formula (i) to formula (m): (i) (j) (k) (l) or (m); The molar concentration of solution 2 is 1×10 -2 mol / L.

[0025] Furthermore, the molar concentration of solution 3 is 1×10 -3 mol / L, the volume ratio of water and THF is 1:9.

[0026] Furthermore, the volume ratio of water, DMF and THF in the mixed solution of water, DMF and THF is 2:3:5, and the concentration of solution 4 is 5×10 −3 M.

[0027] The beneficial effect of adopting a further technical solution is that in the imidazolium salt ionic liquid environment, the metal ions that produce a coordination effect with the organic free radical molecules produce a violent charge transfer between the free radical molecules, thereby changing the excited state and the emission state of the free radical luminescent system, which can lead to a change in the emission wavelength of the free radical luminescent material.

[0028] The present invention also provides the application of the inorganic-organic hybrid carbonyl free radical luminescent material in metal ion detection.

[0029] The beneficial effects of the present invention are: the inorganic-organic hybrid carbonyl free radical luminescent material of the present invention has good free radical stability and can be used with Cd 3+ , Pb 3+ The detection of metal ions such as heavy metals can be achieved through ferroelectric effect and metal bridge effect. The detection sensitivity is high and stable, and it has excellent industrial prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The emission spectra of the inorganic-organic hybrid carbonyl radical luminescent materials of Examples 1 to 6; Figure 2 The absorption spectra of the inorganic-organic hybrid carbonyl radical luminescent materials of Examples 1 to 6; Figure 3 is the EPR spectrum of AC5-Fe; Figure 4 FT-IR spectra of AC5 and AC5-Fe after illumination; Figure 5 X-ray photoelectron spectra of AC5 and AC5-Fe; Figure 6 is the fluorescence lifetime diagram of AC5 and AC5-Fe; Figure 7 is the kinetic decay curve of the steady-state emission spectra of AC5 and AC5-Fe; Figure 8 AC5-Fe responds to different Cd concentrations 3+ Emission spectrum of Fig. 9 AC5-Fe and luminescence intensity-heavy metal ions (Cd 3+ )’s concentration linear relationship diagram; Fig.10 AC5-Fe responds to different concentrations of Pb 2+ Emission spectrum of Fig.11 AC5-Fe and luminescence intensity-heavy metal ions (Pb 2+ )’s concentration linear relationship diagram; Fig.12 Schematic diagram of the fluorescence emission intensity changes of AC5-Fe detecting other metal ions Figure 1 ; Fig.13 Schematic diagram of the fluorescence emission intensity changes of AC5-Fe detecting other metal ions Figure 2 ; Fig.14 AC5-Fe for detecting Pb in industrial wastewater 2+ Actual site map; Fig.15 AC5-Fe for detecting Cd in industrial wastewater 3+ Actual on-site map. DETAILED DESCRIPTION

[0031] The specific implementation modes of the present invention are described in detail below with reference to the embodiments.

[0032] Example 1 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (a): Formula (a); The preparation method comprises the following steps: S1: Dissolve 1,3,5-triacetylbenzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Fe(NO 3 ) 3 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed at a volume ratio of 5:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material AC5-Fe.

[0033] Example 2 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (b): Formula (b); The preparation method comprises the following steps: S1: Dissolve 1,3,5-trialdehyde benzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Fe(NO 3 ) 3 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed in a volume ratio of 4:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target section solvent, and then spinning the solvent to dryness), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 40 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material BC5-Fe.

[0034] Example 3 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (c): Formula (c); The preparation method comprises the following steps: S1: Dissolve 1,3,5-triacetylbenzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Ni(NO 3 ) 2 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed in a volume ratio of 6:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material AC5-Ni.

[0035] Example 4 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (d): Formula (d); The preparation method comprises the following steps: S1: Dissolve 1,3,5-trialdehyde benzene in acetone to obtain a molar concentration of 5×10-3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Ni(NO 3 ) 2 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed at a volume ratio of 5:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material BC5-Ni.

[0036] Example 5 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (e): Formula (e); The preparation method comprises the following steps: S1: Dissolve 1,3,5-triacetylbenzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, MnSO 4 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed at a volume ratio of 5:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material AC5-Mn.

[0037] Example 6 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (f): Formula (f); The preparation method comprises the following steps: S1: Dissolve 1,3,5-trialdehyde benzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, MnSO 4 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed at a volume ratio of 5:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material BC5-Mn.

[0038] Example 7 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (g): Formula (g); The preparation method comprises the following steps: S1: Dissolve 1,3,5-triacetylbenzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Co(NO 3 ) 2 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed in a volume ratio of 5:1, heated to 126°C and refluxed for 6 h. After the reaction was completed, the mixture was cooled to room temperature, purified by column chromatography, and vacuum dried at 60°C to constant weight to obtain an intermediate product. S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material AC1-Co.

[0039] Example 8 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (h): Formula (h); The preparation method comprises the following steps: S1: Dissolve 1,3,5-trialdehyde benzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Co(NO3 ) 2 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed at a volume ratio of 5:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material BC2-Co.

[0040] Example 9 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (a): Formula (a); The preparation method comprises the following steps: S1: Dissolve 1,3,5-triacetylbenzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Fe(NO 3 ) 3 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed at a volume ratio of 5:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target solvent, and then spinning the solvent dry), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and Solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material AC3-Fe.

[0041] Example 10 An inorganic-organic hybrid carbonyl free radical luminescent material, the structure of which is shown in formula (b): Formula (b); The preparation method comprises the following steps: S1: Dissolve 1,3,5-trialdehyde benzene in acetone to obtain a molar concentration of 5×10 -3 mol / L solution 1, dissolve the imidazolium salt ionic liquid in acetone to obtain a molar concentration of 1×10 -2 mol / L solution 2, Fe(NO 3 ) 3 Dissolved in a mixed solution of water and THF (the volume ratio of water to THF was 1:9) to obtain a molar concentration of 1×10 -3 mol / L solution three; the structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 3 were mixed in a volume ratio of 4:1, heated to 126°C and refluxed for 6 hours. After the reaction was completed, the mixture was cooled to room temperature and purified by column chromatography (using analytical grade silica gel powder as the stationary phase, dry loading, first washing the stationary phase in the column with petroleum ether, then rinsing with a mixed solvent of methanol and dichloromethane in a volume ratio of 1:50, collecting the target section solvent, and then spinning the solvent to dryness), and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: The intermediate product was dissolved in a mixture of water, DMF and THF (the volume ratio of water, DMF and THF was 2:3:5) to obtain solution 4 (concentration of 5×10 -3 M); S4: Solution 2 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 40 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material BC4-Fe.

[0042] Comparative Example A carbonyl free radical luminescent material, the preparation method of which comprises the following steps: S1: Prepare 1,3,5-triacetylbenzene in acetone as solution 1 (molar concentration of 5×10 -3 mol / L), prepare an acetone solution of imidazolium salt ionic liquid as solution 2 (molar concentration is 1×10 -2 mol / L) The structural formula of the imidazolium salt ionic liquid used is as follows: ; S2: Solution 1 and solution 4 were mixed in a volume ratio of 50:1, and then ultrasonicated for 30 minutes. After the ultrasonication, the mixed solution was dried at 70°C until the sample was in a fluid state, thereby obtaining the inorganic-organic hybrid carbonyl radical luminescent material AC5.

[0043] Experimental Example 1 Emission spectrum test: 300 μL AC5-Mn, AC5-Fe, AC5-Ni, BC5-Mn, BC5-Fe and BC5-Ni were added to six four-way cuvettes (optical path length 2 mm), and each sample was first photoactivated for 30 seconds using a handheld UV lamp with an emission wavelength of 365 nm and a power of 3 W. Then, the emission spectrum of the above three samples was tested in a HORIBA FluoreMax+ fluorescence instrument with an excitation wavelength of 365 nm and a slit of 2 nm. The results are shown in the figure. Figure 1 As shown, the emission spectrum of AC5-Fe shows a cyan-blue emission near 475nm. Although the emission spectra of the other systems are slightly different from that of AC5-Fe, they are almost consistent with the emission color of AC5-Fe in terms of emission colors visible to the naked eye.

[0044] Experimental Example 2 UV-Visible absorption spectrum test: The absorption spectrum test of the free radical sample used to test the emission spectrum in Experimental Example 1 was performed using Shimazu ultraviolet spectrophotometer UV3600PLUS. The results are as follows: Figure 2 As shown, both have significant absorption peaks and broad absorption bands at 350nm and 400nm-500nm, respectively, with typical free radical absorption characteristics.

[0045] Experimental Example 3 Electron paramagnetic resonance test: Use Bruker EMXnano spectrometer to perform EPR test on AC5-Fe. Dilute the prepared AC5-Fe sample with acetone solvent to 500μL, then add 20mg of 5,5-dimethyl-1-pyrroline N-oxide (DMPO) to the sample, and ultrasonicate the mixed sample for 10 minutes. After using a capillary to absorb the sample, irradiate the capillary with a handheld UV lamp with an emission wavelength of 365nm for 1 minute. After completion, put the capillary into the instrument test chamber for testing. The results are as follows: Figure 3 As shown, it shows obvious signal characteristics of carbonyl radical.

[0046] Experimental Example 4 Fourier transform infrared spectroscopy test: AC5-Fe and AC5 were mixed with potassium bromide and pressed into tablets for testing. The results are as follows: Figure 4 As shown in the figure, compared with the infrared spectrum of AC5, the carbonyl vibration peak on pyromellitic trialdehyde shifts significantly to a lower wave number, indicating that Fe in the organic-inorganic hybrid free radical system of the present invention 3+ Interaction with the carbonyl group.

[0047] Experimental Example 5 X-ray Photoelectron Spectroscopy Test: AC5 and AC5-Fe were tested by X-ray Photoelectron Spectroscopy using Thermo Scientific K-Alpha. The results are as follows Figure 5 As shown in the figure, compared with AC5, there is no new binding energy diffraction peak in the O1s high-resolution spectrum of AC5-Fe, which proves that no covalent bond is formed between compound A and the metal ion; however, the O1s spectrum of AC5-Fe has an overall shift toward the high binding energy direction, indicating that the carbonyl group and Fe 3+ There are non-covalent interactions between them.

[0048] Experimental Example 6 Photoluminescence fluorescence lifetime test: Use HORIBA FluoreMax+ fluorescence instrument to test the fluorescence lifetime of AC5 and AC5-Fe. Figure 6 As shown, the fluorescence lifetimes of AC5 and AC5-Fe are 7.28 ns and 8.56 ns, respectively.

[0049] Experimental Example 7 Photoluminescence steady-state kinetic test: The kinetic curves of the steady-state emission spectra of AC5 and AC5-Fe were also tested using the HORIBA FluoreMax+ fluorescence instrument. Figure 7As shown in the figure, the natural quenching rate of AC5 in dark environment is much greater than that of AC5-Fe, indicating that the doping of Fe 3+ The radical lifetime of the organic-inorganic hybrid free radical system is much longer than the free radical lifetime of the undoped carbonyl organic free radical system.

[0050] Experimental Example 8 Metal ion detection application 1: Using AC5-Fe as a sensor probe, its effect on Pb 2+ and Cd 3+ The sensing performance of two heavy metal ions was firstly prepared with different concentrations of Pb 2+ Solution (H 2 O:THF, v / v=1:9), the concentration is 10 - 8 M, 2×10 -8 M, 4×10 -8 M, 6×10 -8 M, 8×10 -8 M, 10 -7 M, 2×10 -7 M, 4×10 -7 M, 6×10 -7 M, 8×10 -7 M. The AC5-Fe that has been activated by ultraviolet light is sequentially exposed to Pb from low concentration to high concentration. 2+ The solution was incubated for 5 minutes, and then the emission spectra at each incubation concentration were measured. 3+ The sensing linearity experiment was performed with the addition of Cd 3+ Except for the solution, everything else is the same.

[0051] The experimental results are as follows Figures 8 to 11 As shown, AC5-Fe has a significant effect on Pb 2+ The response is a Turn on response ( Figure 8 ), the linear equation is: Lg(I R / I B )=0.0197c Pb +0.6669, R 2 =0.9953, linear range is 10 -7 ~7×10 -7 mol / L, the detection limit is 3.3×10 -8 mol / L( Fig. 9 ) (where I R for Figure 8 The emission peak intensity near 550nm, I B for Figure 8 The emission peak intensity is located near 470nm in AC5-Fe to Cd 3+The response is a Turn off response ( Fig.10 ), the linear equation is: 10 -6 LgI=-0.2363c Cd =+0.8575, R 2 = 0.9957 and 10 -6 LgI=-0.6857c Cd +3.129, R 2 =0.9978, the linear range is 1.3×10 -5 ~9.1×10 -5 mol / L, the detection limit is 4.3×10 -6 mol / L( Fig.11 ) (where I is Fig.10 The emission peak intensity is located near 570nm).

[0052] Experimental Example 9 Metal ion detection application 2: preparation concentration is 8×10 -8 M of other metal ions (H 2 O:THF, v / v=1:9). Including Na + , Hg 2+ , Ni 2+ ,Co 2+ and Cr 3+ The test process is the same as that of Experiment 8. Figures 12-13 As shown in the figure, the emission of AC5-Fe is almost unchanged when other metal ions exist, indicating that the AC5-Fe free radical system provided by the present invention has an effect on Pb 2+ and Cd 3 + It has good detection specificity.

[0053] Experimental Example 10 Practical application of simulated industrial wastewater: the concentration is 10 -7 M of Pb 2+ Solution (the solvent is tap water). In order to simulate the industrial wastewater environment containing heavy metal particles, the above solution also contains Na + , Hg 2+ , Ni 2+ ,Co 2+ and Cr 3+ Metal ions (concentrations were 10 -7 M). Take 15 μL of the simulated wastewater prepared above and add it dropwise to the AC5-Fe system prepared in advance and activated by ultraviolet light, sonicate for 5 minutes, and then excite AC5-Fe by ultraviolet light again. The experimental results are as follows: Fig.14 As shown, AC5-Fe responds to Pb 2+The actual sample is AC5-Fe@Pb, and its free radical emission intensity is significantly improved compared with that before responding to the actual sample; 3+ In the process of preparing simulated wastewater, in addition to adding Pb 2+ Replace with Cd 3+ Except for this, the remaining steps are the same as those for preparing Pb-containing 2+ The experimental results are consistent with the simulated industrial wastewater. Fig.15 As shown, AC5-Fe responds to Cd 3+ The actual sample is AC5-Fe@Cd, and its free radical emission intensity is obviously quenched before responding to the actual sample.

[0054] Although the specific implementation of the present invention is described in detail in conjunction with the embodiments, it should not be understood as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. An inorganic-organic hybrid carbonyl radical luminescent material, characterized in that: Its structure is shown in formula (I): （Ⅰ）， Wherein, R is H or CH3, M is a transition metal ion, and X is an inorganic acid radical.

2. The inorganic-organic hybrid carbonyl free radical luminescent material according to claim 1, characterized in that: The M is Mn 2 + 、Co 2+ , Fe 3+ or Ni 2+ .

3. The inorganic-organic hybrid carbonyl free radical luminescent material according to claim 1, characterized in that: The X is SO4 2- or NO3 - .

4. The inorganic-organic hybrid carbonyl free radical luminescent material according to claim 1, characterized in that: The luminescent material is one of the compounds represented by formula (a) to formula (h): （a）、 （b）、 （c）、 （d）、 （e）、 （f）、 (g) or （h）。 5. The method for preparing the inorganic-organic hybrid carbonyl free radical luminescent material according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: preparing an acetone solution of tricarbonyl-substituted benzene organic small molecule as solution 1, preparing an acetone solution of imidazole salt ionic liquid as solution 2, and preparing a mixed solution of water and THF of inorganic metal salt as solution 3; S2: Solution 1 and solution 3 were mixed in a volume ratio of 4-6:1, heated to 126°C and refluxed for 6 hours, cooled to room temperature after the reaction was completed, purified by column chromatography, and vacuum dried at 60°C to constant weight to obtain an intermediate product; S3: dissolving the intermediate product in a mixture of water, DMF and THF to obtain solution 4; S4: Solution 2 and solution 4 are mixed in a volume ratio of 50:1, and then ultrasonicated for 30-40 minutes. After the ultrasonication, the mixed solution is dried at 70°C until the sample is in a fluid state, thereby obtaining an inorganic-organic hybrid carbonyl radical luminescent material.

6. The method for preparing the inorganic-organic hybrid carbonyl free radical luminescent material according to claim 5, characterized in that: The tricarbonyl-substituted benzene organic small molecule is 1,3,5-triacetylbenzene or 1,3,5-trialdehydebenzene, and the molar concentration of the solution is 5×10 -3 mol / L.

7. The method for preparing the inorganic-organic hybrid carbonyl free radical luminescent material according to claim 5, characterized in that: The imidazolium salt ionic liquid is one of the compounds represented by formula (i) to formula (m): (i) (j) (k) (l) or (m); The molar concentration of solution 2 is 1×10 -2 mol / L.

8. The method for preparing the inorganic-organic hybrid carbonyl free radical luminescent material according to claim 5, characterized in that: The molar concentration of solution three is 1×10 -3 mol / L, the volume ratio of water and THF is 1:

9.

9. The method for preparing the inorganic-organic hybrid carbonyl free radical luminescent material according to claim 5, characterized in that: The volume ratio of water, DMF and THF in the mixed solution of water, DMF and THF is 2:3:5, and the concentration of the solution 4 is 5×10 -3 M.

10. Use of the inorganic-organic hybrid carbonyl free radical luminescent material according to any one of claims 1 to 4 in metal ion detection.

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