Preparation method of paper-based self-reinforced nickel-organic framework electrochemical luminescent material

Abstract

The invention provides the preparation method of the paper-based self-reinforced nickel-organic framework electrochemical luminescent material, which is reasonable in design and simple to operate. A novel efficient electrochemical luminescent material is successfully prepared by assembling a luminous body 4, 4-(anthracene-9, 10-diyl) dibenzoic acid and a co-reactant triethylene diamine on a nickel ion node. The material does not need an exogenous co-reactant, and can effectively shorten the mass transfer distance and reduce the electron transfer resistance, thereby reducing the energy loss and improving the electron transfer efficiency, and further improving the electrochemical luminescence performance of the material. Therefore, due to the fact that the self-enhanced nickel-organic framework electrochemical luminescent material has a rigid repeated structure, the organic light-emitting bodies are orderly arranged at proper intervals, the immobilization amount of the organic light-emitting bodies is increased, excitation of the internal light-emitting bodies is facilitated, and the self-enhanced nickel-organic framework electrochemical luminescent material has a wide application prospect in the field of electrochemical luminescence.

Description

Technical Field

[0001] The invention relates to a method for preparing a paper-based self-enhanced nickel-organic framework electrochemical luminescent material, belonging to the technical field of preparation of composite nano materials. Background Art

[0002] The permanent porosity and rigid framework structure of metal-organic framework materials give them excellent stability, the potential to load a large number of luminophores, and host-guest responsiveness. The luminescence properties of luminescent metal-organic framework materials can be derived from the organic linkers or metal ions of the framework itself, or from guest molecules in the framework pores, such as dyes, perovskite materials, and carbon dots. The luminescence of the framework material itself is mostly related to the organic ligands containing tertiary amine conjugated systems. Self-enhanced nickel-organic frameworks are luminescent metal-organic framework materials that use strong fluorescent organic luminescent groups such as anthracene as ligands to construct a network structure. It not only avoids the fluorescence quenching of excimers that often occur between planar conjugated molecules, but also effectively prolongs the luminescence lifetime. Therefore, it is expected to be used in host-guest luminescence sensing. Electrochemiluminescence is a specific chemiluminescence reaction initiated by electrochemistry on the electrode surface. It does not require the introduction of an excitation light source, thereby effectively avoiding the interference of stray light. It has low background signals, excellent spatiotemporal controllability, and a wide dynamic range. Traditional electrochemiluminescent materials mainly include ruthenium bipyridine, luminol, quantum dots, nanoclusters and perovskite materials. These nanomaterials need to find a balance between structural stability and luminescence efficiency to achieve a sustained and stable luminescence effect. In addition, in the co-reactant type electrochemiluminescence system, the intermolecular reaction between the luminophore and the co-reactant is usually achieved by directly adding the exogenous co-reactant to the test solution. However, the longer intermolecular electron transfer path will undoubtedly increase the energy loss and hinder the electron transfer process, which will lead to a decrease in luminescence efficiency and detection sensitivity. Summary of the invention

[0003] In view of the above-mentioned problems currently existing in traditional electrochemiluminescent materials, this technical solution provides a method for preparing a paper-based self-enhanced nickel-organic framework electrochemiluminescent material with a reasonable design and simple operation. By assembling the luminophore 4,4-(anthracene-9,10-diyl)dibenzoic acid and the co-reactant triethylenediamine on the nickel ion node, a new type of high-efficiency electrochemiluminescent material was successfully prepared. This material does not require exogenous co-reactants, can effectively shorten the mass transfer distance, reduce the electron transfer resistance, thereby reducing energy loss and improving the electron transfer efficiency, and thus can improve the electrochemiluminescent performance of the material. Therefore, in view of the fact that the self-enhanced nickel-organic framework electrochemiluminescent material has a rigid and repetitive structure, the organic luminophores are arranged in an orderly manner at appropriate spacings, which increases the solid loading of the organic luminophores and is conducive to the excitation of the luminophores, showing broad application prospects in the field of electrochemiluminescence.

[0004] The method for preparing the paper-based self-enhanced nickel-organic framework electrochemical luminescent material comprises the following steps: (1) dissolving nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine in 10-30 mL of N,N-dimethylformamide solution, wherein the molar ratio of nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine is 1-2:1-2:1-2; (2) Transfer the mixed solution obtained in step (1) to a 25 mL or 50 mL stainless steel reactor lined with polytetrafluoroethylene, seal and tighten the reactor, and place it in a preheated oven at 110-160 °C for 24-48 h. After the reaction is completed, cool it naturally to room temperature, centrifuge the obtained sample, wash it three times with N,N-dimethylformamide solution, and dry it in a 60 °C vacuum drying oven for 10-12 h to obtain a light green powder sample; (3) The overall layout pattern of the paper chip was designed using the drawing software Adobe Illustrator CS6. Then, the front and back patterns of the design were transferred to the surface of A4-sized cellulose paper using a solid wax printer and an HP LaserJet P1008 printer, respectively. The cellulose paper with the printed pattern was placed in a 90 °C oven for baking to allow the wax to penetrate the entire thickness of the paper, forming a hydrophilic area surrounded by a hydrophobic wall, which was used as the sample test area, and then cut into individual paper chips; (4) Preparation of gold seed solution: Mix 70-90 mL of aqueous solution with 0.5-1 mL of 1% chloroauric acid and heat to 90°C. Then add 2-3 mL of 1% sodium citrate solution, stir and heat for 15 min, and then cool naturally to room temperature to obtain a gold seed solution. (5) Preparing a gold electrode on the hydrophilic area of ​​the single paper chip obtained in step (3): dripping the gold seed solution obtained in step (4) on the hydrophilic area, waiting for it to dry, and repeating the dripping three times, mixing 100-200 µL of 1% chloroauric acid and 100-200 µL of 200 mM hydroxylamine hydrochloride, and then rapidly dripping it onto the surface of the hydrophilic area of ​​the paper chip, rinsing the surface of the paper chip with deionized water after 20 min, and drying at room temperature; (6) Drawing electrodes: Use a pencil and a highly conductive silver ink pen purchased from a store to apply normal hand pressure to draw electrodes on the dotted areas on the front and back of the paper chip. Use a pencil to draw on area a on the front and area b on the back of the paper chip to construct the working electrode and counter electrode, respectively. Use a silver ink pen to draw on area c on the back of the paper chip to construct the reference electrode. After drawing, dry the electrodes at room temperature for 20 min. (7) Take 0.001-0.003 g of the sample obtained in step (2) and place it in 1 mL of deionized water, and disperse it by ultrasonic oscillation to form a uniform white suspension; (8) Take 200-400 μL of the suspension obtained in step (7) and drop it onto the surface of the gold electrode obtained in step (5), and dry it at room temperature; (9) Connect the electrode obtained in step (8) to an electrochemiluminescence instrument and test it in a PBS solution with a pH value of 7.4; the voltage range of the electrochemiluminescence tester is set to 0 - 1.2 V, the scanning speed is 0.15 V / s, the amplification level is 4, and the photomultiplier tube voltage is 650 V.

[0005] The sample morphology obtained in step (2) is a rectangular parallelepiped with a length of about 1.1 μm, a width of about 300 nm, and a height of about 150 nm.

[0006] The pencil model used in step (6) is 5B or 6B.

[0007] Beneficial effects of the present invention

[0008] (1) The luminophore and co-reactant ligands are assembled in a grid-like manner on the metal node, which reduces the mass transfer distance between the luminophore and the co-reactant, reduces energy loss, and improves detection sensitivity.

[0009] (2) The material synthesis steps are simple to operate, environmentally friendly, and the conditions are relatively mild.

[0010] (3) Self-enhanced nickel-organic framework electrochemiluminescent materials have a rigid and repetitive structure, which increases the solid loading of the organic light-emitting body and is conducive to the excitation of the light-emitting body, showing broad application prospects in the field of electrochemiluminescence.

[0011] (4) This method uses paper as the base material, which has the advantages of large specific surface area, low cost, green environmental protection and integration.

[0012] (5) Hand-drawn electrodes do not require complex manufacturing processes, can flexibly adjust the design and size, are easy to mass-produce, do not generate industrial waste, and have little impact on the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 . Schematic diagram of the overall layout pattern design of the paper chip.

[0015] Figure 2 . Schematic diagram of paper chip dimensions.

[0016] Figure 3 . Draw a schematic diagram of the electrodes.

[0017] Figure 4 . Scanning electron microscope image of self-reinforced nickel-organic framework material.

[0018] Figure 5. Fluorescence excitation and emission spectra of self-enhanced nickel-organic framework materials.

[0019] Figure 6 . Electrochemiluminescence intensity response diagram of self-enhanced nickel-organic framework materials. DETAILED DESCRIPTION

[0021] Example 1 (1) Nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine were dissolved in 10 mL of N,N-dimethylformamide solution, wherein the molar ratio of nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine was 2:2:1; (2) The mixed solution obtained in step (1) was transferred to a 25 mL stainless steel reactor lined with polytetrafluoroethylene, the reactor was sealed and tightened, and the reactor was placed in a preheated oven at 120 °C for 24 h. After the reaction was completed, the mixture was naturally cooled to room temperature, the obtained sample was centrifuged, washed three times with N,N-dimethylformamide solution, and then placed in a 60 °C vacuum drying oven for drying for 10 h to obtain a light green powder sample; (3) The overall layout pattern of the paper chip was designed using the drawing software Adobe Illustrator CS6. Then, the front and back patterns of the design were transferred to the surface of A4-sized cellulose paper using a solid wax printer and an HP LaserJet P1008 printer, respectively. The cellulose paper with the printed pattern was placed in a 90 °C oven for baking to allow the wax to penetrate the entire thickness of the paper, forming a hydrophilic area surrounded by a hydrophobic wall, which was used as the sample test area, and then cut into individual paper chips; (4) Preparation of gold seed solution: Mix 80 mL of aqueous solution with 0.8 mL of 1% chloroauric acid and heat to 90 °C. Then add 2.8 mL of 1% sodium citrate solution, stir and heat for 15 min, and then cool naturally to room temperature to obtain a gold seed solution. (5) Prepare a gold electrode on the hydrophilic area of ​​the single paper chip obtained in step (3): drip the gold seed solution obtained in step (4) on the hydrophilic area, wait for it to dry and repeat the dripping three times, mix 150 µL of 1% chloroauric acid and 150 µL of 200 mM hydroxylamine hydrochloride and quickly drip it on the surface of the hydrophilic area of ​​the paper chip, rinse the surface of the paper chip with deionized water after 20 minutes, and dry it at room temperature; (6) Drawing electrodes: Use a 6B pencil and a highly conductive silver ink pen purchased from a store to apply normal hand pressure to draw electrodes on the dotted areas on the front and back of the paper chip. Use a 6B pencil to draw on area a on the front and area b on the back of the paper chip to construct the working electrode and counter electrode, respectively. Use a silver ink pen to draw on area c on the back of the paper chip to construct the reference electrode. After drawing, dry the electrodes at room temperature for 20 min. (7) Take 0.001 g of the sample obtained in step (2) and place it in 1 mL of deionized water. Disperse it by ultrasonic oscillation to form a uniform white suspension. (8) Take 300 μL of the suspension obtained in step (7) and drop it onto the surface of the gold electrode obtained in step (5), and dry it at room temperature; (9) Connect the electrode obtained in step (8) to an electrochemiluminescence instrument and test it in a PBS solution with a pH value of 7.4; the voltage range of the electrochemiluminescence tester is set to 0 - 1.2 V, the scanning speed is 0.15 V / s, the amplification level is 4, and the photomultiplier tube voltage is 650 V.

[0022] Example 2 The preparation steps are the same as those in Example 1, except that in step (1), nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine are dissolved in 10 mL of N,N-dimethylformamide solution, wherein the molar ratio of nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine is 1:2:1.

[0023] Example 3 The preparation steps are the same as those in Example 1, except that in step (2), the mixed solution obtained in step (1) is transferred to a 25 mL stainless steel reactor lined with polytetrafluoroethylene, the reactor is sealed and tightened, and the reactor is placed in a preheated oven at 120°C for reaction for 48 h. After the reaction is completed, the mixture is naturally cooled to room temperature, the obtained sample is centrifuged, washed three times with N,N-dimethylformamide solution, and then dried in a 60°C vacuum drying oven for 10 h to obtain a light green powder sample.

Claims

1. A method for preparing a paper-based self-enhanced nickel-organic framework electrochemiluminescent material, characterized in that: The following steps are involved: (1) Dissolve nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine in 10-30 mL of N,N-dimethylformamide solution, wherein the molar ratio of nickel chloride hexahydrate, 4,4-(anthracene-9,10-diyl)dibenzoic acid and triethylenediamine is 1-2:1-2:1-2; (2) Transfer the mixed solution obtained in step (1) to a 25 mL or 50 mL stainless steel reactor lined with polytetrafluoroethylene, seal and tighten the reactor, and place it in a preheated oven at 110-160 °C for 24-48 h. After the reaction is completed, cool it naturally to room temperature, centrifuge the obtained sample, wash it three times with N,N-dimethylformamide solution, and dry it in a 60 °C vacuum drying oven for 10-12 h to obtain a light green powder sample; (3) The overall layout pattern of the paper chip was designed using the drawing software Adobe Illustrator CS6. Then, the front and back patterns of the design were transferred to the surface of A4-sized cellulose paper using a solid wax printer and an HP LaserJet P1008 printer, respectively. The cellulose paper with the printed pattern was placed in a 90 °C oven for baking to allow the wax to penetrate the entire thickness of the paper, forming a hydrophilic area surrounded by a hydrophobic wall, which was used as the sample test area, and then cut into individual paper chips; (4) Preparation of gold seed solution: Mix 70-90 mL of aqueous solution with 0.5-1 mL of 1% chloroauric acid and heat to 90 °C. Then add 2-3 mL of 1% sodium citrate solution, stir and heat for 15 min, and then cool naturally to room temperature to obtain a gold seed solution. (5) Preparing a gold electrode on the hydrophilic area of ​​the single paper chip obtained in step (3): dripping the gold seed solution obtained in step (4) on the hydrophilic area, waiting for it to dry, and repeating the dripping three times, mixing 100-200 µL of 1% chloroauric acid and 100-200 µL of 200 mM hydroxylamine hydrochloride, and then rapidly dripping it onto the surface of the hydrophilic area of ​​the paper chip, rinsing the surface of the paper chip with deionized water after 20 min, and drying at room temperature; (6) Drawing electrodes: Use a pencil and a highly conductive silver ink pen purchased from a store to apply normal hand pressure to draw electrodes on the dotted areas on the front and back of the paper chip. Use a pencil to draw on area a on the front and area b on the back of the paper chip to construct the working electrode and counter electrode, respectively. Use a silver ink pen to draw on area c on the back of the paper chip to construct the reference electrode. After drawing, dry the electrodes at room temperature for 20 min. (7) Take 0.001-0.003 g of the sample obtained in step (2) and place it in 1 mL of deionized water, and disperse it by ultrasonic oscillation to form a uniform white suspension; (8) Take 200-400 μL of the suspension obtained in step (7) and drop it onto the surface of the gold electrode obtained in step (5), and dry it at room temperature; (9) Connect the electrode obtained in step (8) to an electrochemiluminescence instrument and test it in a PBS solution with a pH value of 7.4; the voltage range of the electrochemiluminescence tester is set to 0 - 1.2 V, the scanning speed is 0.15 V / s, the amplification level is 4, and the photomultiplier tube voltage is 650 V.

2. The method for preparing a paper-based self-enhanced nickel-organic framework electrochemical luminescent material as claimed in claim 1, characterized in that The pencil model mentioned in step (6) is one of 5B or 6B.

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