CN115575372A - Manufacturing method of oxygen sensor fluorescent film, oxygen sensor fluorescent film and oxygen sensor - Google Patents

Abstract

The method for manufacturing the oxygen sensor fluorescent film, the oxygen sensor fluorescent film and the oxygen sensor comprises the following steps: s1: coating a fluorescence indicator in a ZIF-8 material to obtain a ZIF-8 composite material coated with the fluorescence indicator; s2: preparing a fluorescent layer mixed solution, wherein the fluorescent layer mixed solution contains a ZIF-8 composite material coated with a fluorescent indicator; s3: providing a substrate, and solidifying the fluorescent layer mixed solution on the substrate to form a fluorescent layer on the substrate; s4: and forming a shading breathable layer on one side of the fluorescent layer, which is far away from the substrate. The oxygen sensor manufactured by the method can improve the dispersion degree and the uniformity of the fluorescent indicator on the carrier, improve the air permeability of the fluorescent film of the oxygen sensor, improve the sensitivity of the oxygen sensor to oxygen and shorten the response time.

Description

Manufacturing method of oxygen sensor fluorescent film, oxygen sensor fluorescent film and oxygen sensor

technical field

The invention relates to the technical field of sensors, in particular to a method for manufacturing an oxygen sensor fluorescent film, an oxygen sensor fluorescent film and an oxygen sensor.

Background technique

In many fields such as biology, medicine, environment, and industrial process, it is necessary to measure the concentration of gaseous oxygen or dissolved oxygen.

Compared with the traditional oxygen sensing technology, the fluorescence-oxygen sensing technology based on the fluorescence quenching effect has the characteristics of fast response, short equilibration time, no oxygen consumption during the test process, and low temperature operation. Due to the above advantages, fluorescent oxygen sensors have been widely used in the fields of chemistry, biology, clinical medicine and environmental monitoring in the world.

The fluorescence quenching effect mainly uses oxygen to quench the fluorescence of some fluorescent substances, and the oxygen content is determined according to the fluorescence intensity or quenching time. The key component of the fluorescence-oxygen sensor is the fluorescent oxygen-sensitive membrane material that can produce fluorescence emission. Sensitive films are usually formed by embedding fluorescent compounds in a solid matrix and then coating them to form a film.

The development of technology has higher and higher requirements for the response speed of the fluorescence-oxygen sensor. Based on the above principles and structures, the loading and dispersion of fluorescent indicator molecules on the carrier and the oxygen permeability of the film-forming organic matrix are the key factors that restrict the improvement of the response speed of the fluorescence-oxygen sensor.

Contents of the invention

In view of this, the present invention provides a method for making an oxygen sensor fluorescent film, an oxygen sensor fluorescent film and an oxygen sensor. The oxygen sensor produced by the method can improve the dispersion and uniformity of the fluorescent indicator on the carrier, and improve the oxygen sensor. The gas permeability of the fluorescent film of the oxygen sensor improves the sensitivity of the oxygen sensor to oxygen and shortens the response time.

The invention provides a method for making a fluorescent film of an oxygen sensor, comprising the following steps:

S1: coating the fluorescent indicator in the ZIF-8 material to obtain the ZIF-8 composite material coated with the fluorescent indicator;

S2: Prepare a fluorescent layer mixed solution, the fluorescent layer mixed solution contains a ZIF-8 composite material coated with a fluorescent indicator;

S3: providing a substrate, curing the fluorescent layer mixed solution on the substrate to form a fluorescent layer on the substrate;

S4: forming a light-shielding and air-permeable layer on a side of the fluorescent layer away from the base.

Further, when forming the ZIF-8 composite material coated with fluorescent indicator, the method also includes:

Dissolving zinc nitrate hexahydrate in solution A, and adding a surfactant to obtain solution A containing zinc ions; and dissolving 2-methylimidazole and fluorescent indicator in solution B to obtain solution containing fluorescent indicator and 2 - B solution of methylimidazole;

The solution A and the solution B are mixed, stirred, centrifuged and dried to obtain a ZIF-8 composite material coated with a fluorescent indicator.

Further, the A solution is a methanol solution, and the B solution is a mixed solution of methanol and tetrahydrofuran.

Further, the surfactant is cetyltrimethylammonium bromide, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer, Span, Tween, polyethylene One or more mixtures of pyrrolidones.

Further, the fluorescent indicator is PtOEP, PtOEPK or PtTFPP platinum porphyrin complexes, tris(2,2'-bipyridyl)ruthenium(II) complexes, tris(1,10-phenanthroline) Ruthenium(Ⅱ) complex, tris(4.7-diphenyl-1.10-phenanthroline)ruthenium(Ⅱ) complex or tris(5-amino-1,10-phenanthroline)ruthenium(Ⅱ) one or more of.

Further, when performing step S2, the ZIF-8 composite material coated with the fluorescent indicator and the polymer matrix are dissolved together in an organic solution to form a fluorescent layer mixed solution.

Further, in the ZIF-8 composite material coated with a fluorescent indicator, the molar ratio of the ZIF-8 material to the fluorescent indicator is 10000:1-15; in the fluorescent layer, the The mass ratio of ZIF-8 composite material to polymer matrix is 1:100-1000.

Further, when forming the light-shielding air-permeable layer, the method includes: uniformly mixing the raw material of the light-shielding air-permeable layer with the curing agent, adding the light-shielding pigment and stirring evenly to form a light-shielding air-permeable layer mixture, and coating the light-shielding air-permeable layer mixture on the The fluorescent layer is on the side away from the base, and is cured to form the light-shielding and air-permeable layer.

The present invention also provides a fluorescent film of an oxygen sensor, which is produced by the above-mentioned production method of the fluorescent film of an oxygen sensor.

The present invention also provides an oxygen sensor, comprising the above-mentioned oxygen sensor fluorescent film.

In the present invention, the ZIF-8 composite material coated with the fluorescent indicator is formed by coating the fluorescent indicator in the ZIF-8 material, and then the composite material is dispersed in the fluorescent layer. Because the ZIF-8 material has a porous structure, the fluorescent indicator can be more easily coated in the ZIF-8, which can prevent the fluorescent indicator from gathering in the fluorescent layer and improve the uniformity of the fluorescent indicator in the fluorescent layer; further , the porous structure of ZIF-8 combines with the pores of the polymer matrix to form gas diffusion channels and enhance the gas permeability of the membrane. Therefore, the fluorescent film of the oxygen sensor can effectively improve the dispersion of the fluorescent indicator in the polymer matrix and ensure the uniformity of the fluorescent layer; on the other hand, the synergistic effect of ZIF-8 and the polymer matrix makes the oxygen sensor The fluorescent film can have high air permeability to improve the sensitivity and response time to oxygen.

Further, the present invention adds light-shielding pigments into the light-shielding air-permeable layer to ensure the transmission of oxygen while blocking the interference of other light signals and pollutants. The thickness of the protective layer can be controlled by using a four-sided coating machine to prepare a thin protective layer to reduce the Small oxygen sensing membrane thickness. The thickness of the oxygen sensing membrane is thin and the volume is small, which is conducive to further application in miniaturized oxygen detection devices. The perfect protective structure can be waterproof and anti-pollution. The difference between each sensing membrane is small, and the membrane can be replaced at any time without affecting the oxygen sensor. measurement accuracy. The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable , the following preferred embodiments are specifically cited below, and are described in detail as follows in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a schematic flowchart of each step of a method for manufacturing a fluorescent film of an oxygen sensor provided by an embodiment of the present invention.

Figure 2 shows the phase change of the fluorescent film of the oxygen sensor after adding different components of ZIF-8 materials and fluorescent indicators to the fluorescent film of the oxygen sensor provided by the present invention.

Figure 3 shows the influence of different mass ratios of the composite material to the polymer matrix on the performance of the oxygen sensor fluorescent film when the molar ratio of the ZIF-8 material to the fluorescent indicator is 10000:12.

Fig. 4 is a schematic structural diagram of the oxygen sensor fluorescent film provided by the embodiment of the present invention.

detailed description

In order to further explain the technical means and functions adopted by the present invention to achieve the intended invention purpose, the detailed description is as follows in conjunction with the accompanying drawings and preferred embodiments.

The invention provides a method for making a fluorescent film of an oxygen sensor, a fluorescent film of an oxygen sensor and an oxygen sensor. The oxygen sensor produced by the method can improve the degree of dispersion and uniformity of a fluorescent indicator on a carrier, and improve the fluorescence film of the oxygen sensor. The gas permeability improves the oxygen sensor's sensitivity to oxygen and shortens the response time.

Fig. 1 is a schematic flow chart of each step of the method for making the fluorescent film of the oxygen sensor provided by the embodiment of the present invention. As shown in Fig. 1, the method for making the fluorescent film of the oxygen sensor includes the following steps:

S1: Coating the fluorescent indicator in the ZIF-8 (zeolite imidazolate framework) material to obtain the ZIF-8 composite material coated with the fluorescent indicator;

In this step, 0.1 to 0.4 mol of zinc nitrate hexahydrate can be dissolved in 50 to 200 ml of A solution, such as methanol solution, and then 1 to 10% of the mass fraction of surfactant is added to completely dissolve to obtain A solution of zinc ions; and 0.2 to 2 mol of 2-methylimidazole and 0.01 to 0.06 mmol of fluorescent indicator dissolved in B solution, such as 50 to 200 ml of methanol and tetrahydrofuran mixed solution, preferably, the volume ratio of methanol to tetrahydrofuran It is 1:1, obtains the B solution that contains fluorescent indicator and 2-methylimidazole;

Slowly add solution A into solution B, stir it by magnetic force, and the reaction time is 24h. Centrifuge the reacted solution in a centrifuge at a speed of 4000-10000rpm for 30min to obtain a precipitate, wash the precipitate three times with methanol, and dry it in vacuum at 60°C for 10h. In order to obtain the ZIF-8 composite material coated with the fluorescent indicator.

The fluorescent indicator can be PtOEP, PtOEPK or PtTFPP platinum porphyrin complexes, tris(2,2'-bipyridyl)ruthenium(II) complexes, tris(1,10-phenanthroline)ruthenium(II) One of three (4.7-diphenyl-1.10-phenanthroline) ruthenium (II) complexes or tris (5-amino-1,10-phenanthroline) ruthenium (II) complexes, etc. one or more species.

The surfactant can be CTAB (cetyltrimethylammonium bromide), P123 (polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer), Span, Tween, One or a mixture of polyvinylpyrrolidone (PVP), etc.

Further, the pore diameter of the ZIF-8 is 2-50nm.

S2: Prepare a fluorescent layer mixed solution, the fluorescent layer solution contains a ZIF-8 composite material coated with a fluorescent indicator;

Specifically, the ZIF-8 composite material coated with the fluorescent indicator and the polymer matrix can be dissolved in an organic solution to form a fluorescent layer mixed solution. Wherein, the concentration of the fluorescent indicator in the mixed solution of the fluorescent layer is 1-10 mg/ml, and the dispersion is carried out at a speed of 3000-10000 rpm by shear stirring, and the shear stirring time is 0.5-4 hours.

More specifically, the molar ratio of ZIF-8 to the fluorescent indicator is 10000:1-15; the mass ratio of the ZIF-8 composite material coated with the fluorescent indicator to the polymer matrix is 1:100-1000.

Further, the polymer matrix can be polydimethylsiloxane (PDMS), MQ resin, silicone gel, polystyrene, cellulose derivatives, polytrifluoropropylmethylsiloxane or polytrimethylsiloxane One or more of silicon-1-propyne and the like.

S3: providing a substrate, curing the fluorescent layer mixed solution on the substrate to form a fluorescent layer on the substrate;

In this step, while the fluorescent layer mixed solution is being heated, an automatic scraper coating device can be used to scrape the fluorescent layer mixed solution onto the substrate, and finally perform room temperature curing to form a fluorescent layer on the substrate.

The thickness of the substrate can be 50-300 μm; the thickness of the fluorescent layer can be 10-200 μm.

S4: forming a light-shielding and air-permeable layer on the side of the fluorescent layer away from the substrate to form a fluorescent film of the oxygen sensor.

In this step, after uniformly mixing the raw materials of the light-shielding and air-permeable layer with the curing agent, adding the light-shielding pigment and stirring uniformly to form the mixture of the light-shielding and air-permeable layer, after uniformly stirring the mixture of the light-shielding and air-permeable layer, use a four-sided film coater to coat the surface of the fluorescent layer far away from the substrate. on one side, and cured to form a light-shielding and air-permeable layer on the fluorescent layer.

Wherein, the thickness of the light-shielding and air-permeable layer is 10-100 μm, the curing temperature is 50-150° C., and the curing time can be 2-48 hours. The mass ratio of the light-shielding air-permeable layer raw material to the curing agent is 1:0.1-1, and the mass fraction of the light-shielding pigment in the light-shielding air-permeable layer mixture is 0.1-5%.

Wherein, the raw material of the light-shielding air-permeable layer can be polydimethylsiloxane; the light-shielding pigment can be carbon black or white color essence.

In the present invention, the ZIF-8 composite material coated with the fluorescent indicator is formed by coating the fluorescent indicator in the ZIF-8 material, and then the composite material is dispersed in the fluorescent layer. Because the ZIF-8 material has a porous structure, the fluorescent indicator can be more easily coated in the ZIF-8, which can prevent the fluorescent indicator from gathering in the fluorescent layer and improve the uniformity of the fluorescent indicator in the fluorescent layer; further , the porous structure of ZIF-8 combines with the pores of the polymer matrix to form gas diffusion channels and enhance the gas permeability of the membrane. Therefore, the fluorescent film of the oxygen sensor can effectively improve the dispersion of the fluorescent indicator in the polymer matrix and ensure the uniformity of the fluorescent layer; on the other hand, the synergistic effect of ZIF-8 and the polymer matrix makes the oxygen sensor The fluorescent film can have high air permeability to improve the sensitivity and response time to oxygen.

Further, the present invention adds light-shielding pigments into the light-shielding air-permeable layer to ensure the transmission of oxygen while blocking the interference of other light signals and pollutants. The thickness of the protective layer can be controlled by using a four-sided coating machine to prepare a thin protective layer to reduce the Small oxygen sensing membrane thickness. The thickness of the oxygen sensing membrane is thin and the volume is small, which is conducive to further application in miniaturized oxygen detection devices. The perfect protective structure can be waterproof and anti-pollution. The difference between each sensing membrane is small, and the membrane can be replaced at any time without affecting the oxygen sensor. measurement accuracy.

Figure 2 shows the phase change of the fluorescent film of the oxygen sensor after adding different components of ZIF-8 materials and fluorescent indicators to the fluorescent film of the oxygen sensor provided by the present invention.

As shown in Figure 2, the solvent is toluene, the polymer matrix is MQ resin, the fluorescent indicator is three (2,2'-bipyridine) ruthenium (II) complexes, and the mass ratio of the composite material to the polymer matrix is Take 1:300 as an example, change the molar ratio of the ZIF-8 material (indicated by a in Figure 2) and the fluorescent indicator (indicated by b in Figure 2), and measure the fluorescence in the fluorescent film of different oxygen sensors by the phase method , to obtain the total phase corresponding to different nanoparticles at different times.

It can be seen from Figure 2 that since the initial phases of each sample in the air are consistent during measurement, and the time to reach the highest phase is almost the same, the total phase actually reflects the phase change within the same time period, and the change value is large. It is relatively sensitive.

Further, since each sample is from air oxygen concentration to oxygen-free concentration, the larger the phase difference, the more accurate the corresponding oxygen concentration will be.

Therefore, it can be concluded from FIG. 2 that the overall phase of the oxygen sensor fluorescent film made by the method of the present application reflects a relatively large excellent performance.

Figure 3 shows the influence of different mass ratios of the composite material to the polymer matrix on the performance of the oxygen sensor fluorescent film when the molar ratio of the ZIF-8 material to the fluorescent indicator is 10000:12.

It can be seen from Figure 3 that the greater the ratio of the ZIF-8 composite coated with fluorescent indicator (indicated by c in Figure 3) to the polymer matrix (indicated by d in Figure 3), the better its performance.

Fig. 4 is a schematic structural diagram of the oxygen sensor fluorescent film provided by the embodiment of the present invention. As shown in FIG. 4 , the present invention also provides an oxidation sensor fluorescent film, which is manufactured by the above-mentioned manufacturing method of the oxidation sensor fluorescent film.

Specifically, the oxygen sensor fluorescent film includes a substrate 10, a fluorescent layer 20, and a light-shielding and air-permeable layer 30 stacked in sequence, and the fluorescent layer 20 includes a polymer matrix, a fluorescent indicator, and nano-micron particles.

The present invention also provides an oxygen sensor, including the above-mentioned fluorescent film of the oxygen sensor. For other technical features of the oxygen sensor, please refer to the prior art, which will not be repeated here.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this field Those skilled in the art, without departing from the scope of the technical solution of the present invention, may use the technical content disclosed above to make some changes or modify them into equivalent embodiments with equivalent changes, but as long as they do not depart from the technical solution of the present invention, the Technical Essence Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solution of the present invention.

Claims (10)

1. A method for making an oxygen sensor fluorescent film, characterized in that: comprise the steps: S1: coating the fluorescent indicator in the ZIF-8 material to obtain the ZIF-8 composite material coated with the fluorescent indicator; S2: Prepare a fluorescent layer mixed solution, the fluorescent layer mixed solution contains a ZIF-8 composite material coated with a fluorescent indicator; S3: providing a substrate, curing the fluorescent layer mixed solution on the substrate to form a fluorescent layer on the substrate; S4: forming a light-shielding and air-permeable layer on a side of the fluorescent layer away from the base. 2. the manufacture method of oxygen sensor fluorescent film according to claim 1 is characterized in that: when forming the ZIF-8 composite material that described fluorescent indicator is coated with, this method also comprises: Dissolving zinc nitrate hexahydrate in solution A, and adding a surfactant to obtain solution A containing zinc ions; and dissolving 2-methylimidazole and fluorescent indicator in solution B to obtain solution containing fluorescent indicator and 2 - B solution of methylimidazole; The solution A and the solution B are mixed, stirred, centrifuged and dried to obtain a ZIF-8 composite material coated with a fluorescent indicator. 3 . The method for making a fluorescent membrane of an oxygen sensor according to claim 2 , wherein the solution A is a methanol solution, and the solution B is a mixed solution of methanol and tetrahydrofuran. 4 . 4. the manufacture method of oxygen sensor fluorescent film according to claim 1 is characterized in that: described tensio-active agent is hexadecyl trimethyl ammonium bromide, polyethylene oxide-polypropylene oxide-polyethylene oxide One or a mixture of three block copolymers of ethylene oxide, Span, Tween and polyvinylpyrrolidone. 5. The preparation method of the oxygen sensor fluorescent film according to claim 1, characterized in that: the fluorescent indicator is PtOEP, PtOEPK or PtTFPP platinum porphyrin complex, three (2,2'-bipyridine) ruthenium (Ⅱ) complex, tris(1,10-phenanthroline) ruthenium(Ⅱ) complex, tris(4.7-diphenyl-1.10-phenanthroline) ruthenium(Ⅱ) complex or tri One or more of (5-amino-1,10-phenanthroline) ruthenium (II). 6. the preparation method of oxygen sensor fluorescent film according to claim 1 is characterized in that: when carrying out S2 step, the ZIF-8 composite material that will be coated with fluorescent indicator and polymer matrix are dissolved in organic solution jointly , to form a fluorescent layer mixed solution. 7. the manufacture method of oxygen sensor fluorescent film according to claim 6 is characterized in that: in the ZIF-8 composite material that is coated with fluorescent indicator, the mol ratio of ZIF-8 material and fluorescent indicator is 10000:1-15; in the fluorescent layer, the mass ratio of the ZIF-8 composite material coated with the fluorescent indicator to the polymer matrix is 1:100-1000. 8. The preparation method of the oxygen sensor fluorescent film according to claim 1, characterized in that: when forming the light-shielding air-permeable layer, the method comprises: uniformly mixing the light-shielding air-permeable layer raw materials with the curing agent, and adding light-shielding pigments to stir evenly to A light-shielding and air-permeable layer mixture is formed, and the light-shielding and air-permeable layer mixture is coated on the side of the fluorescent layer away from the substrate and cured to form the light-shielding and air-permeable layer. 9. A fluorescent film for an oxygen sensor, characterized in that it is produced by the method for producing a fluorescent film for an oxygen sensor according to any one of claims 1 to 8. 10. An oxygen sensor, characterized by comprising the fluorescent film of the oxygen sensor according to claim 9.

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