阅读说明：本技术 一种氧化石墨相氮化碳及其制备方法和应用 (Graphite oxide phase carbon nitride and preparation method and application thereof ) 是由 徐鑫 于俊玲 董宾宾 郝绿原 于 2019-09-17 设计创作，主要内容包括：本发明提供了一种氧化石墨相氮化碳及其制备方法和应用,本发明提供的氧化石墨相氮化碳通过将前驱体石墨相氮化碳溶于浓硝酸溶液中,依次加入高锰酸钾和双氧水反应,得到氧化石墨相氮化碳；其中,通过采用浓硝酸和高锰酸钾对前驱体石墨相氮化碳进行氧化反应,使得制备得到的氧化石墨相氮化碳用于检测碘离子的荧光探针具有选择性好、灵敏度高、信噪比高、可靠性好、无毒、生物相容性好的优点。在细胞及生物活体的碘离子检测中具有很好的应用前景。(The invention provides a graphite oxide phase carbon nitride and a preparation method and application thereof, wherein the graphite oxide phase carbon nitride is prepared by dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, and sequentially adding potassium permanganate and hydrogen peroxide for reaction; the prepared fluorescent probe for detecting the iodide ions by using the graphite-phase carbon nitride precursor has the advantages of good selectivity, high sensitivity, high signal-to-noise ratio, good reliability, no toxicity and good biocompatibility. Has good application prospect in the detection of iodide ions of cells and living organisms.)

1. A method for preparing graphite oxide phase carbon nitride comprises the following steps:

dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, and sequentially adding potassium permanganate and hydrogen peroxide for reaction to obtain graphite oxide phase carbon nitride.

2. The method of claim 1, wherein the precursor graphite-phase carbon nitride is prepared by the following method:

putting melamine powder into a crucible, covering the crucible, putting the crucible into a muffle furnace, and performing high-temperature solid phase sintering to obtain precursor graphite phase carbon nitride;

wherein the sintering temperature is 400-600 ℃, the heating rate is 3-7 ℃/min, and the heat preservation time is 1.5-2.5 h.

3. The preparation method of claim 1, wherein the amount ratio of the graphite-phase carbon nitride to the concentrated nitric acid is 1g to (20-30) mL.

4. The preparation method of claim 1, wherein the using amount ratio of the graphite-phase carbon nitride to the potassium permanganate is 1g to (1.5-3).

5. The preparation method according to claim 1, wherein the hydrogen peroxide is 30 w/w% hydrogen peroxide.

6. The method according to claim 1, wherein the method for preparing the graphite oxide phase carbon nitride comprises: dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, mixing and stirring for 20-50 min, then adding potassium permanganate, mixing and stirring for 1-3 h, adding water for diluting, ultrasonically oscillating for 2-3 h, mixing and stirring for 6-10 h, and then adding hydrogen peroxide for reaction to obtain the graphite oxide phase carbon nitride.

7. The method according to claim 6, wherein the temperature of the reaction solution when the potassium permanganate is added is less than 20 ℃.

8. The preparation method of claim 1, wherein after the potassium permanganate and the hydrogen peroxide are sequentially added for reaction, the reaction solution is further centrifuged, washed and dried to obtain the graphite oxide phase carbon nitride.

9. The graphite oxide-phase carbon nitride prepared by the preparation method according to any one of claims 1 to 8, wherein the graphite oxide-phase carbon nitride contains a carboxyl group, wherein the carboxyl group is located at position C2, and the oxygen content in the graphite oxide-phase carbon nitride is 18.00 to 19.50%.

10. A method for detecting iodide ions, comprising:

1) dissolving the graphite oxide phase carbon nitride of claim 9 in water to obtain a colloid;

2) adding the iodine ion solution to be detected into the colloid obtained in the step 1), uniformly mixing, and measuring the fluorescence spectrum of the mixed solution to obtain the content of iodine ions in the solution to be detected.

Technical Field

The invention relates to the technical field of ion detection, and relates to graphite oxide phase carbon nitride and a preparation method and application thereof.

Background

Iodide, as an intellectual element of the human body, plays an important role in various biological activities such as nervous system and thyroid function. Insufficient iodine intake in the body can lead to insufficient synthesis of thyroid hormone; and iodine deficiency occurs during the embryonic period or after the birth of the infant, which affects brain development, resulting in mental deterioration. Meanwhile, the body damage caused by excessive iodine also draws more and more attention. The iodine intake for a long time or the iodine intake with a high dose at one time can cause great damage to the body and even cause the occurrence of certain tumors. Therefore, the detection of the content of iodide ions, especially the detection of the content of iodide in cells or organisms, is an important research work. However, the reported fluorescent probes for detecting iodide ions are mainly classified into two types: one is a fluorescence quenching mode based on hydrogen bonding electrostatic interactions, but it is susceptible to interference from other fluorescence quenchers. This will result in false positive signals, resulting in a lower signal-to-noise ratio and poor reliability. The other is a fluorescence-on mode based on coordination of metal and iodide ions, but the introduction of heavy metal ions during detection greatly limits their application in living organisms.

Therefore, the method for determining the content of the iodide ions has the advantages of accurate measurement result, high efficiency and low toxicity and is of great significance.

Disclosure of Invention

In view of the above, the technical problem to be solved by the present invention is to provide a graphite oxide phase carbon nitride, and a preparation method and an application thereof.

The invention provides a preparation method of graphite oxide phase carbon nitride, which comprises the following steps:

dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, and sequentially adding potassium permanganate and hydrogen peroxide for reaction to obtain graphite oxide phase carbon nitride.

Preferably, the precursor graphite phase carbon nitride is prepared by the following method:

putting melamine powder into a crucible, covering the crucible, putting the crucible into a muffle furnace, and performing high-temperature solid phase sintering to obtain precursor graphite phase carbon nitride;

wherein the sintering temperature is 400-600 ℃, the heating rate is 3-7 ℃/min, and the heat preservation time is 1.5-2.5 h.

Preferably, the using amount ratio of the graphite-phase carbon nitride to the concentrated nitric acid is 1g to (20-30) mL.

Preferably, the using amount ratio of the graphite-phase carbon nitride to the potassium permanganate is 1g to (1.5-3) g.

Preferably, the hydrogen peroxide is 30 w/w% hydrogen peroxide.

Preferably, the preparation method of the graphite oxide phase carbon nitride comprises the following steps: dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, mixing and stirring for 20-50 min, then adding potassium permanganate, mixing and stirring for 1-3 h, adding water for diluting, ultrasonically oscillating for 2-3 h, mixing and stirring for 6-10 h, and then adding hydrogen peroxide for reaction to obtain the graphite oxide phase carbon nitride.

Preferably, the temperature of the reaction solution when potassium permanganate is added is less than 20 ℃.

Preferably, after potassium permanganate and hydrogen peroxide are sequentially added for reaction, the reaction solution is further subjected to centrifugation, washing and drying to obtain the graphite oxide phase carbon nitride.

The invention also provides the graphite oxide phase carbon nitride prepared by the preparation method, wherein the graphite oxide phase carbon nitride contains carboxyl groups, and the carboxyl groups are positioned at the C2 position.

The invention also provides a detection method of iodide ions, which comprises the following steps:

1) dissolving the graphite oxide phase carbon nitride in water to obtain colloid;

2) adding the iodine ion solution to be detected into the colloid obtained in the step 1), uniformly mixing, and measuring the fluorescence spectrum of the mixed solution to obtain the content of iodine ions in the solution to be detected.

Compared with the prior art, the invention provides graphite oxide phase carbon nitride and a preparation method and application thereof, the graphite oxide phase carbon nitride provided by the invention is prepared by dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, and sequentially adding potassium permanganate and hydrogen peroxide for reaction; the prepared fluorescent probe for detecting the iodide ions by using the graphite oxide phase carbon nitride has the advantages of good selectivity, high sensitivity, high signal-to-noise ratio, good reliability, no toxicity and good biocompatibility. Has good application prospect in the detection of iodide ions of cells and living organisms.

Drawings

FIG. 1 is a FI-IR spectrum of a graphite phase carbon nitride and a graphite oxide phase carbon nitride;

FIG. 2 is a single layer g-C₃N₄A molecular structure;

FIG. 3 is a C1s spectrum of graphite phase carbon nitride and graphite oxide phase carbon nitride;

FIG. 4 is a N1s spectrum of graphite phase carbon nitride and graphite oxide phase carbon nitride;

FIG. 5 is a graph showing fluorescence spectra of a graphite oxide phase carbon nitride mixture with different iodide ion concentrations, wherein the internal graph shows the fluorescence intensity (I) of the system₀I) fitting a relation curve of the concentration of the iodide ions to obtain a linear relation graph;

FIG. 6 is an electron layout diagram of front tracks of graphite oxide phase carbon nitride molecules with iodine ions, and fluorine ions unbound;

FIG. 7 is a schematic diagram of the mechanism of quenching and turning on fluorescence of a quenching system of graphite oxide-phase carbon nitride added with iodide under acid-base regulation;

FIG. 8 is a graph showing the change in fluorescence intensity for different anion solutions added to a graphite oxide phase carbon nitride colloid followed by an alkaline solution.

Detailed Description

The invention provides a preparation method of graphite oxide phase carbon nitride, which comprises the following steps:

dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, and sequentially adding potassium permanganate and hydrogen peroxide for reaction to obtain graphite oxide phase carbon nitride.

According to the invention, a precursor graphite-phase carbon nitride is dissolved in a concentrated nitric acid solution, and potassium permanganate and hydrogen peroxide are sequentially added for reaction to obtain graphite oxide-phase carbon nitride; the using amount ratio of the graphite-phase carbon nitride to the concentrated nitric acid is preferably 1g to (20-30) mL, and more preferably 1g to (22-28) mL; the dosage ratio of the graphite-phase carbon nitride to the potassium permanganate is preferably 1g to (1.5-3) g, and more preferably 1g to (2-2.5) g; the hydrogen peroxide is preferably 30 w/w% hydrogen peroxide.

In the present invention, in order to make the reaction proceed more smoothly, the preferred method for preparing the graphite oxide phase carbon nitride of the present invention is: dissolving a precursor graphite-phase carbon nitride in a concentrated nitric acid solution, and mixing and stirring for 20-50 min, preferably for 30-40 min; then adding potassium permanganate, mixing and stirring for 1-3 hours, preferably mixing and stirring for 2-2.5 hours, adding water for dilution, ultrasonically oscillating for 2-3 hours, mixing and stirring for 6-10 hours, preferably mixing and stirring for 8-9 hours, and then adding hydrogen peroxide for reaction to obtain graphite oxide phase carbon nitride; wherein the temperature of the reaction solution when the potassium permanganate is added is lower than 20 ℃; and adding hydrogen peroxide to reduce the excessive potassium permanganate, and stirring while adding the hydrogen peroxide until the reaction mixture turns to milk white.

In the invention, the preparation method of the precursor graphene carbon nitride has no special requirements, and can be any preparation method known in the art, and the precursor graphite phase carbon nitride is preferably prepared according to the following method: putting melamine powder into a crucible, covering the crucible, putting the crucible into a muffle furnace, and performing high-temperature solid phase sintering to obtain precursor graphite phase carbon nitride; wherein the sintering temperature is preferably 400-600 ℃, more preferably 500-550 ℃, and the heating rate is preferably 3-7 ℃/min, more preferably 5-6 ℃/min; the heat preservation time is preferably 1.5-2.5 h.

In the invention, preferably, the mixed solution obtained by sequentially adding potassium permanganate and hydrogen peroxide for reaction is sequentially centrifuged, washed and dried to obtain graphite oxide phase carbon nitride; wherein the centrifugal speed is preferably 4000 to 9000rpm, and more preferably 5000 to 8000 mm.

The invention also provides the graphite oxide phase carbon nitride prepared by the preparation method, wherein the graphite oxide phase carbon nitride contains carboxyl groups, and the carboxyl groups are positioned at C2; the oxygen content in the graphite oxide phase carbon nitride is preferably 18.00-19.50%, more preferably 18.30-19.30%, and more preferably 18.56-19.10%; the carboxyl is formed by oxidizing graphite phase carbon nitride and breaking C2 bonded carbon-nitrogen bond.

The invention also provides a detection method of iodide ions, which comprises the following steps:

1) dissolving the graphite oxide phase carbon nitride in water to obtain colloid;

2) adding the iodine ion solution to be detected into the colloid obtained in the step 1), uniformly mixing, and measuring the fluorescence spectrum of the mixed solution to obtain the content of the iodine ion concentration in the solution to be detected.

According to the invention, the graphite oxide phase carbon nitride is dissolved in water to obtain colloid; wherein the dosage ratio of the graphite oxide phase carbon nitride to the distilled water is 1g to (180-250) mL, and more preferably 1g to (200-220) mL. In the invention, stable colloid is preferably obtained by ultrasonic oscillation.

According to the invention, the iodine ion solution to be detected is added into the colloid obtained in the step 1) and mixed evenly, and the fluorescence spectrum of the mixed solution is measured to obtain the content of the iodine ion concentration in the solution to be detected. In the application, the mixed solution quenched by the to-be-detected iodide ion solution can be added with the sodium hydroxide solution to be restarted, and compared with the traditional iodide ion fluorescence quenching type probe, the quenching-starting type probe has higher reliability.

The invention provides a graphite oxide phase carbon nitride and a preparation method and application thereof, wherein the graphite oxide phase carbon nitride is prepared by dissolving a precursor graphite phase carbon nitride in a concentrated nitric acid solution, and sequentially adding potassium permanganate and hydrogen peroxide for reaction; the prepared fluorescent probe for detecting the iodide ions by using the graphite oxide phase carbon nitride has the advantages of good selectivity, high sensitivity, high signal-to-noise ratio, good reliability, no toxicity and good biocompatibility. Has good application prospect in the detection of iodide ions of cells and living organisms.

The following will clearly and completely describe the technical solutions of the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.