阅读说明：本技术 一种萘二酰亚胺基金属有机框架薄膜的制备方法及其在水合肼检测上的应用 (Preparation method of naphthalene diimide-based metal organic framework film and application of naphthalene diimide-based metal organic framework film in hydrazine hydrate detection ) 是由 郭智勇 林俊宇 于 2019-09-25 设计创作，主要内容包括：本发明属于多孔材料合成与应用领域,具体涉及一种萘二酰亚胺基金属有机框架薄膜的制备方法及其在水合肼检测上的应用。本发明通过将含有萘二酰亚胺基的配体、六水合硝酸锌、N,N-二甲基甲酰胺、水、乙醇和涂有纳米氧化锌的FTO玻璃在一次性闪烁瓶中用水热法制备萘二酰亚胺基金属有机框架薄膜。所制备的薄膜对水合肼蒸汽具有良好的识别作用。该方法新颖独特,实验步骤简单,不需要复杂的后处理过程,一步反应即可得到所需薄膜,且制备成薄膜为该材料在离子识别上等领域上提供了很好的应用前景。(The invention belongs to the field of porous material synthesis and application, and particularly relates to a preparation method of a naphthalene diimide-based metal organic framework thin film and application of the naphthalene diimide-based metal organic framework thin film in hydrazine hydrate detection. The invention prepares the naphthalimide-based metal organic framework film by a hydrothermal method in a disposable scintillation bottle by using a naphthalimide-based ligand, zinc nitrate hexahydrate, N-dimethylformamide, water, ethanol and FTO glass coated with nano zinc oxide. The prepared film has good recognition effect on hydrazine hydrate steam. The method is novel and unique, the experimental steps are simple, the required film can be obtained through one-step reaction without a complex post-treatment process, and the prepared film provides a good application prospect for the material in the fields of ion recognition and the like.)

1. A preparation method of a naphthalene diimide base metal organic framework film is characterized in that: the method comprises the following steps:

1) preparation of metal organic framework ligand DSNDI based on naphthalene diimide: adding 1.5g of 1,4,5, 8-naphthalene tetracarboxylic anhydride, 2.58g of p-aminosalicylic acid, 7mL of trimethylchlorosilane and 8mL of DMF (dimethyl formamide) into a single-neck flask, reacting for 14 hours at 140 ℃, and filtering and purifying after the temperature is reduced to room temperature to obtain a yellow powder product;

2) preparing a nano zinc oxide film: cutting FTO glass into 1 x 4cm²Ultrasonically cleaning the glass, drying the glass, covering two ends of the FTO glass, spin-coating a nano zinc oxide solution on the middle part of the FTO glass on a spin coater with the rotation speed of 1000 rpm, annealing the glass in a tube furnace and slowly cooling the glass to room temperature;

3) preparation of naphthalene diimide base metal organic framework thin film: 6mg of zinc nitrate hexahydrate, 5.66mg of DSNDI ligand, 0.6mL of H were added to a scintillation vial₂After O, 0.6mL of ethanol and 9mL of DMF, inserting FTO glass coated with nano zinc oxide into the solution in an inclined way, and reacting for 9 hours at the temperature of 90 ℃; and cooling to normal temperature, and cleaning and exchanging.

2. The method of preparing a naphthalene diimide-based metal organic framework thin film according to claim 1, wherein: in the step 1), the filtering and purifying are to pour the solid product into ethyl acetate and deionized water solution in turn, perform ultrasonic treatment for 30min respectively, filter, and dry at 80 ℃ to obtain yellow powder.

3. The method of preparing a naphthalene diimide-based metal organic framework thin film according to claim 1, wherein: in the step 2), the step of covering the two ends of the FTO glass means that after cleaning and drying, the two ends of the FTO glass are covered by using a transparent adhesive tape, and 1 x 1cm is left in the middle part of the FTO glass²The area of (a) is used for spin coating the nano zinc oxide solution.

4. The method of preparing a naphthalene diimide-based metal organic framework thin film according to claim 1, wherein: in the step 2), the mass ratio of the ZnO to the ethanol in the spin-coated nano zinc oxide solution is 9: 1.

5. The method of preparing a naphthalene diimide-based metal organic framework thin film according to claim 1, wherein: in the step 2), the nano zinc oxide solution is spin-coated for two times, and 15uL is sequentially spin-coated.

6. The method of preparing a naphthalene diimide-based metal organic framework thin film according to claim 1, wherein: in the step 2), annealing is to spin-coat the nano zinc oxide solution, remove the transparent adhesive tape, place the FTO glass coated with the nano zinc oxide in a tube furnace, then introduce nitrogen into the tube furnace and keep the temperature for 30min, and then raise the temperature of the tube furnace to 350 ℃ at a temperature raising rate of 30 ℃/min and keep the temperature for 30 min.

7. The method of preparing a naphthalene diimide-based metal organic framework thin film according to claim 1, wherein: in the step 3), the cleaning exchange is 5 times of soaking and cleaning by using 100mL of DMF, each soaking is 6 hours, and then methanol is used as an exchange solvent, each time 20mL of methanol solvent is used for 6 hours, and the total exchange is 5 times.

8. A naphthalene diimide-based metal organic framework thin film prepared according to the method of claim 1 ~ 7.

9. Use of the naphthalene diimide-based metal organic framework thin film prepared according to the method of claim 1 ~ 7 in vapor detection of hydrazine hydrate.

Technical Field

The invention belongs to the field of porous material synthesis and application, and particularly relates to a preparation method of a naphthalene diimide-based metal organic framework thin film and application of the naphthalene diimide-based metal organic framework thin film in hydrazine hydrate detection.

Background

Metal organic framework compounds (MOFs) are porous crystalline materials with periodic network structures formed by self-assembly processes of small molecule ligands and metal ions. MOFs have characteristics of porosity, structural and functional diversity, unsaturated metal sites, and the like, and their applications mainly include gas storage, gas separation, small molecule recognition, drug delivery, heterogeneous catalysis, and the like, and thus have received great attention.

Hydrazine hydrate is a strong reducing agent and basic compound that is widely used in industry. Hydrazine hydrate has extremely high toxicity, is unstable under anhydrous conditions, is volatile at normal temperature, and can enter human bodies from skin, oral cavities or respiratory tracts, thereby causing serious injury to the human bodies. Hydrazine hydrate detection methods are various, and common methods include gas chromatography, electrochemical technology, high performance liquid chromatography, capillary electrophoresis, titration and the like. However, these conventional methods generally have many disadvantages or disadvantages, such as slow kinetics in the detection process of hydrazine hydrate using a simple conventional working electrode in the electrochemical assay. Chromatographic-type assays are generally long and expensive in equipment. Therefore, it is of great practical significance to search a simple, practical and environment-friendly method for detecting hydrazine hydrate.

The metal organic framework compound is widely applied to detecting cations, anions, organic small molecules, toxic gases and the like, and has the advantages of quick response, high sensitivity and the like. The application of the film prepared from the metal organic framework compound in molecular recognition not only can improve the uniformity and stability of the film, but also can realize low cost on the premise of keeping the original various advantages, thereby further promoting the development of visual sensing.

In recent years, many research groups have been devoted to the preparation of MOFs thin films, which are fabricated into thin films that still maintain the same crystal structure and properties as powders, enabling low-cost, convenient and efficient practical applications, such as in catalytic membranes, functional electronics, gas or liquid separations, and the like.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a preparation method of a naphthalene diimide-based metal organic framework thin film and application of the thin film in hydrazine hydrate detection. The method is novel and unique, the experimental steps are simple, the required film can be obtained through one-step reaction without complex post-treatment process, and the prepared film provides great application prospect for the material.

In order to achieve the purpose, the invention adopts the following technical scheme:

a preparation method of a naphthalene diimide base metal organic framework film comprises the following steps:

1) preparation of metal organic framework ligand of naphthalene diimide (DSNDI): 1.5g of 1,4,5, 8-naphthalene tetracarboxylic anhydride, 2.58g of p-aminosalicylic acid, 7mL of trimethylchlorosilane and 8mL of DMF are proportionally added into a single-neck flask, reacted for 14 hours at the temperature of 140 ℃, and filtered and purified after the temperature is reduced to obtain a yellow powder product;

2) cutting FTO glass into 1 x 4cm²Ultrasonic cleaning with deionized water, ethanol and acetone for 30min respectively, drying at 100 deg.C for 12 hr, covering two ends of FTO glass with transparent adhesive tape, and leaving an area of 1 x 1cm in the middle². And spin-coating the nano zinc oxide solution on the middle part of the FTO glass on a spin-coating machine. The scotch tape was removed and annealed in a tube furnace and slowly cooled to room temperature.

3) 6mg of zinc nitrate hexahydrate, 5.66mg of DSNDI ligand, 0.6mL of ethanol, 0.6mL of H were added to a scintillation vial₂O and 9mL of DMF, and the mixed solution was sonicated for 10 min. The FTO glass coated with the nano zinc oxide is obliquely inserted into a scintillation vial and reacted for 9 hours at the temperature of 90 ℃. And cooling to normal temperature, and cleaning and exchanging.

Further, in the step 1), the filtering and purifying are to pour the solid product into ethyl acetate and deionized water solution in sequence, perform ultrasonic treatment for 30min respectively, filter, and dry at 80 ℃ to obtain yellow powder.

Further, in the step 2), the step of covering the two ends of the FTO glass means that after the FTO glass is cleaned and dried, the two ends of the FTO glass are covered by using a transparent adhesive tape, and the FTO glass is covered by the transparent adhesive tapeLeaving 1 x 1cm of the middle part of the glass²The area of (a) is used for spin coating the nano zinc oxide solution.

Further, in the step 2), the mass ratio of the ZnO to the ethanol in the spin-coated nano zinc oxide solution is 9: 1.

Further, in the step 2), the nano zinc oxide solution is spin-coated twice, and 15uL is sequentially spin-coated.

Further, in the step 2), annealing is to spin-coat the nano zinc oxide solution, remove the transparent adhesive tape, place the FTO glass coated with the nano zinc oxide in a tube furnace, then introduce nitrogen into the tube furnace and keep the temperature for 30min, and then raise the temperature of the tube furnace to 350 ℃ at a temperature raising rate of 30 ℃/min and keep the temperature for 30 min.

Further, in the step 3), the cleaning exchange is 5-time soaking cleaning by using 100mL of DMF, each soaking is 6 hours, and then methanol is used as an exchange solvent, each exchange is 6 hours by using 20mL of methanol solvent, and the total exchange is 5 times.

The naphthalene diimide-based metal organic framework thin film prepared by the preparation method is applied to hydrazine hydrate vapor detection.

The invention has the following excellent effects:

1) the invention prepares the film of the naphthalene diimide base metal organic framework by using the FTO glass spin-coated with the nano zinc oxide by a hydrothermal method, and the determination shows that the film is completely consistent with the PXRD of the powdery naphthalene diimide base metal organic framework, namely the method prepares the naphthalene diimide base metal organic framework on the FTO glass without changing the crystal structure of the FTO glass.

2) The film prepared by the invention has a good recognition effect on hydrazine hydrate steam, the color of the film gradually changes from light yellow to brown along with the increase of the time of putting the film in the hydrazine hydrate steam, and the color of the film is darker along with the increase of the time.

3) The method has simple steps and novel method, and the preparation of the metal organic framework film improves the application prospect in the aspects of fuel devices, screen displays, capacitors, sensors and the like.

Drawings

FIG. 1(a) is an optical photograph of a naphthalene diimide-based metal organic framework thin film;

FIG. 1(b) is a color change of a naphthalene diimide-based metal organic framework thin film in hydrazine hydrate vapor;

FIG. 2 is an SEM image of a naphthalene diimide-based metal organic framework thin film;

FIG. 3 is a PXRD pattern of naphthalene diimide based metal organic framework powders and films;

FIG. 4 is a graph showing the UV-visible absorption spectra of a Zn-DSNDI-74 thin film in a closed beaker containing hydrazine hydrate vapor at various time conditions.

Detailed Description

For further disclosure, but not limitation, the present invention is described in further detail below with reference to examples.