阅读说明：本技术 含mn2o2单元的碳材料、制备方法与检测no的应用 (Containing MN2O2Carbon material of unit, preparation method and application for detecting NO ) 是由 邓伟侨 周威 杨丽 谭怡 吴昊 于 2021-08-11 设计创作，主要内容包括：本发明属于气敏材料合成技术和电化学检测领域,具体涉及一种含MN-(2)O-(2)单元的碳材料、制备方法与检测一氧化氮的应用。所述MN-(2)O-(2)单元的结构如式I所示:式I中,M＝Sc、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn或Bi；R-(1)＝-CH-(2)-CH-(2)-、-Ph-或-Ch-。本发明采用含MN-(2)O-(2)单元的碳材料来进行一氧化氮的检测,具有特殊结构的MN-(2)O-(2)单元能够提供优异的一氧化氮催化活性,使得这种含MN-(2)O-(2)单元的碳材料应用于实际一氧化氮检测的过程中,具有低的检测限,能够实现灵敏检测。同时,该材料为非均相材料,检测水溶液中的一氧化氮时,不溶于水,可进行回收利用,大大降低检测成本。(The invention belongs to the field of gas-sensitive material synthesis technology and electrochemical detection, and particularly relates to a gas-sensitive material containing MN 2 O 2 A carbon material of a unit, a preparation method and application for detecting nitric oxide. The MN 2 O 2 The structure of the unit is shown as formula I: in formula I, M ═ Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn or Bi; r 1 ＝‑CH 2 ‑CH 2 -, -Ph-or-Ch-. The invention adopts a system containing MN 2 O 2 Detection of nitric oxide by carbon material of unit, MN with special structure 2 O 2 The unit can provide excellent nitric oxide catalytic activity, so that the MN is contained 2 O 2 The carbon material of the unit is applied to the actual nitric oxide detection process, and the deviceHas low detection limit and can realize sensitive detection. Meanwhile, the material is a heterogeneous material, is insoluble in water when detecting nitric oxide in an aqueous solution, can be recycled, and greatly reduces the detection cost.)

1. Contains MN₂O₂Carbon material of unit, MN₂O₂The structure of the unit is shown as formula I:

in formula I, M ═ Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn or Bi; r₁＝-CH₂-CH₂-, -Ph-or-Ch-.

2. The MN-containing of claim 1₂O₂A method for producing a unitary carbon material, characterized by:

the precursor M-Salen and carbon material are ball milled in certain proportion and calcined at high temperature to prepare MN₂O₂A unit carbon material.

3. The method of claim 2, wherein: the carbon material includes commercial carbon materials and carbon materials prepared by conventional experimental techniques, preferably one or more of acetylene black, carbon black, graphene, and carbon nanotubes.

4. The method of claim 2, wherein: the mass ratio of the precursor M-Salen to the carbon material is 1:1-100, preferably 1: 1.

5. The method of claim 2, wherein: the calcination temperature is 200-900 ℃, preferably 300-900 ℃, and the calcination time is 1-12 hours, preferably 2-3 hours.

6. The method of claim 2, wherein: the said MN₂O₂The preparation method of the unit carbon material comprises the following steps:

mixing and ball-milling a precursor M-Salen and a carbon material according to the mass ratio of 1:1-100, putting the mixture into a tube furnace, introducing inert gas into the mixture, and calcining the mixture at the temperature of 200-₂O₂A unit carbon material.

7. The method of claim 2, wherein: the preparation method of the precursor M-Salen comprises the following steps: taking salicylaldehyde, metal salt and amine compound as organic ligands and absolute ethyl alcohol as a reaction solvent to react to prepare the compound containing MN₂O₂Precursor M-Salen of carbon material.

8. The method of claim 7, wherein: the metal salt compound is acetate, chloride, perchlorate, sulfate, nitrate or diethyl salt.

9. The method of claim 7, wherein: the amine compound is ethylenediamine, cyclohexanediamine or phenylenediamine.

10. The MN-containing of claim 1₂O₂Use of carbon materials of units for the detection of nitric oxide, including but not limited to:

(1) detecting nitric oxide in exhaled breath of a human body;

(2) detection of nitric oxide in solution phase.

Technical Field

The invention belongs to the field of gas-sensitive material synthesis technology and electrochemical detection, and particularly relates to a gas-sensitive material containing MN₂O₂A carbon material of a unit, a preparation method and application for detecting nitric oxide.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

Nitric oxide, a newly recognized information molecule and "star molecule", has attracted considerable attention from life sciences and related disciplines due to its important physiological role in the living body and one of the important factors that destroy the ozone layer. Recently, it has been reported that nitric oxide plays an important regulatory role in plant growth and development, defense against viruses, and the like. Major problems currently faced with respect to the detection of pure nitric oxide gas include:

(1) nitric oxide is chemically very reactive and has a short half-life due to its unpaired free radical electron. The detection process needs to be free from oxygen, which requires that the detection process needs to be completed in an extremely short time.

(2) Due to the instability of the nitric oxide molecule, the lower limit of dilution is 5ppb when preparing low concentrations of nitric oxide, which is detrimental to the investigation of nitric oxide sensor materials.

There are many conventional methods for measuring nitric oxide, and the methods mainly include spectrophotometry, electron spin spectrometry, chemiluminescence, electrochemistry, bioassay, electromagnetic resonance spectrometry, chemiluminescence, laser-induced fluorescence, and the like. The electrochemical method has the characteristics of real-time, continuous and on-site measurement, and is widely popularized and applied, so that the development of the high-efficiency gas sensor material based on the electrochemical means and capable of being directly used for detecting nitric oxide has important significance.

At present, a metal-salen cross-linked material is widely used for detecting nitric oxide by an electrochemical method, for example, a Co-salen/Nafion modified electrode is disclosed in the prior art, nitric oxide can be subjected to electrocatalytic oxidation on the Co-salen/Nafion membrane modified electrode, and then nitric oxide in natural seawater can be measured, but the metal-salen material is a homogeneous material and is difficult to recover after being applied in an aqueous solution, and the catalytic activity of the metal-salen material is limited, so that sensitive detection is difficult to perform when the amount of nitric oxide is low. In addition, the metal-salen material has low conductivity, and is low in efficiency when used for detecting nitric oxide by an electrochemical method.

Disclosure of Invention

In order to solve the defects of the prior art, the invention provides a Mobile Node (MN)₂O₂The invention relates to a carbon material containing unit, a preparation method thereof and application thereof in detecting nitric oxide₂O₂Detection of nitric oxide by carbon material of unit, MN with special structure₂O₂The unit can provide excellent nitric oxide catalytic activity, further has lower detection limit, and can realize sensitive detection. Furthermore, the introduction of the carbon material can provide good conductivity and improve detection efficiency. Meanwhile, the material is a heterogeneous material, is insoluble in water when detecting nitric oxide in an aqueous solution, can be recycled, and greatly reduces the detection cost.

To achieve the above object, the present invention provides, in a first aspect, a MN-containing network₂O₂Carbon material of unit, MN₂O₂The structure of the unit is shown as formula I:

in formula I, M ═ Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn or Bi; r₁＝-CH₂-CH₂-, -Ph- (-Ph-is phenyl) or-Ch- (-Ch-is cyclohexane).

The second aspect of the present invention provides a method for making the above MN₂O₂A method of making a carbon material of a unit, comprising the steps of:

ball milling the precursor M-Salen and a carbon material according to a certain proportion andcalcining at high temperature to obtain MN₂O₂A unit carbon material.

The third aspect of the present invention provides an MN₂O₂Use of a carbon material of a cell for detecting nitric oxide.

One or more embodiments of the present invention have at least the following advantageous effects:

(1) the invention adopts a system containing MN₂O₂Detection of nitric oxide by carbon material of unit, MN with special structure₂O₂The unit can provide excellent nitric oxide catalytic activity, so that the MN is contained₂O₂The carbon material of the unit is applied to the process of detecting the actual content of nitric oxide, has low detection limit, and particularly can achieve the lowest detection concentration of 8ppb in the process of detecting the exhaled breath of a human body, thereby realizing high-sensitivity detection.

(2) The invention provides MN₂O₂The carbon material of unit is heterogeneous material, when detecting nitric oxide, is difficult for dissolving in the aquatic, can retrieve after the detection so, realizes recycling, greatly reduced the detection cost, has also avoided the pollution to the water simultaneously.

(3) The invention connects MN₂O₂The units are supported in a carbon material, the carbon can be MN₂O₂The cell provides excellent conductivity such that it contains MN₂O₂When the carbon material of the unit is applied to the detection of nitric oxide by an electrochemical method, the detection effect is better.

(4) The MN is contained₂O₂The synthesis conditions for the unit carbon material were easy to handle, and the carbon material used for the support was inexpensive and readily available, so that MN was contained in example 1₂O₂The carbon material of the unit can be synthesized in large quantities.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a schematic view of a catalyst system according to the present inventionMN₂O₂A schematic flow chart of the preparation of the unit carbon material;

FIG. 2 shows the NiN content in example 1₂O₂High resolution electron microscopy images of the unit carbon material;

FIG. 3 shows the NiN content in example 1₂O₂A spherical aberration electron micrograph of the unit carbon material;

FIG. 4 shows the NiN content in example 1₂O₂Elemental profile of a unit carbon material;

FIG. 5 shows the NiN content in example 1₂O₂Detecting a cyclic voltammetry curve of solution phase nitric oxide by using a unit carbon material;

FIG. 6 shows the NiN content in example 1₂O₂Detecting a comparison graph of the concentration of nitric oxide in the exhaled gas of the human body and peak current by using the unit carbon material;

FIG. 7 shows Ni-Salen and NiN-containing precursors of example 1₂O₂A peak current contrast graph of detecting 8ppb of human exhaled gas nitric oxide by using a unit carbon material;

FIG. 8 shows the NiN content in example 1₂O₂Time versus peak current plot of 1.8nM nitric oxide in the single carbon material detection solution phase.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

As described in the background art, the Co-salen material widely used in the prior art for detecting nitric oxide is a homogeneous material, and is difficult to recover after being applied in an aqueous solution, and the Co-salen material has a limited catalytic activity, so that it is difficult to perform a sensitive detection when the amount of nitric oxide is low. In addition, the metal-salen material has low conductivity, and is low in efficiency when used for detecting nitric oxide by an electrochemical method.

In order to solve the above technical problems, a first aspect of the present invention provides a MN-containing network₂O₂Carbon material of unit, MN₂O₂The structure of the unit is shown as formula I:

in formula I, M ═ Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn or Bi; r₁＝-CH₂-CH₂-, -Ph- (-Ph-is phenyl) or-Ch- (-Ch-is cyclohexane).

The invention provides MN₂O₂A unitary carbon material prepared by mixing and sintering an M-Salen complex with a carbon material, compared with the M-Salen complex, MN₂O₂The unit generates structural change, and MN is destroyed in the calcining process₂O₂The benzene ring structures at the two ends are reserved for the MN₂O₂And (5) structure. Therefore, this particular MN₂O₂Compared with M-Salen complex, the structure of the complex improves the catalytic activity of nitric oxide, so that the MN-containing complex provided by the invention₂O₂The carbon material of the unit has lower detection lower limit in the process of applying to the detection of nitric oxide, realizes more sensitive detection, and particularly has the lowest detection lower limit of 8ppb when being applied to the detection of nitric oxide in human exhaled breath.

Moreover, the M-Salen complex is a homogeneous material, although the M-Salen complex can be used for detecting nitric oxide in a solution phase by utilizing the catalytic activity of the M-Salen complex, the M-Salen complex has certain water solubility and poor recycling property, so that the detection cost is higher, and meanwhile, when the nitric oxide in a water body in the nature is detected, the nitric oxide is difficult to recover, so that the nitric oxide is difficult to recover, and the detection cost is causedCertain water pollution. The MN contained in the invention₂O₂The carbon material of the unit is a heterogeneous material, and is insoluble in water when detecting nitric oxide in an aqueous solution, so that the carbon material can be recycled after the detection is finished in sequence, the repeated utilization is realized, the detection cost can be effectively reduced, and the pollution to a water body is also avoided.

In addition, the present invention associates MN with₂O₂The unit is supported in a carbon material, the carrier carbon material can be MN₂O₂The unit provides excellent conductivity, so that the unit has more efficient detection effect when being applied to the detection of nitric oxide in human exhaled breath in an electrochemical method.

The second aspect of the present invention provides a method for making the above MN₂O₂A method of making a carbon material of a unit, comprising the steps of:

ball-milling a precursor M-Salen and a carbon material according to a certain proportion and calcining at high temperature to prepare the Mn-containing material₂O₂A unit carbon material.

Wherein, during the calcination process, the structure of the precursor M-Salen is changed to form MN₂O₂The units, while attached in a carbon support, form a composite.

The carbon material in the invention is a carbon material, has no special requirement, and specifically comprises a commercial carbon material and a carbon material prepared by a conventional experimental technology, and is preferably one or more of acetylene black, carbon black, graphene and carbon nanotubes.

The preparation process comprises MN₂O₂The addition ratio of the precursor of the unit to the carbon material has an important influence, the high proportion of the carbon material can reduce the proportion of catalytic active ingredients, and is not favorable for high-efficiency nitric oxide detection, and the low proportion of the carbon material can cause that the precursor M-Salen can not be fully converted into MN₂O₂The unit, too, cannot perform highly sensitive detection. Therefore, as a preferred embodiment, the mass ratio of the precursor M-Salen to the carbon material is 1:1 to 100, and preferably: 1:1.

Further, the calcination temperature is 200-900 ℃, preferably 300-900 ℃, and the calcination time is 1-12 hours, preferably 2-3 hours.

Further, containing MN₂O₂The preparation method of the unit carbon material specifically comprises the following steps:

mixing and ball-milling a precursor M-Salen and a carbon material according to the mass ratio of 1:1-100, putting the mixture into a tube furnace, introducing inert gas into the mixture, and calcining the mixture at the temperature of 200-₂O₂A unit carbon material.

The precursor M-Salen is a material which can be directly obtained in the prior art;

as a preferred embodiment, the preparation method of the precursor M-Salen comprises the following steps: taking salicylaldehyde, metal salt and amine compound as organic ligands and absolute ethyl alcohol as a reaction solvent to react to prepare the compound containing MN₂O₂A precursor M-Salen of a carbon material;

further, the metal salt compound is acetate, chloride, perchlorate, sulfate, nitrate or diethyl salt.

Further, the amine compound is ethylenediamine, cyclohexanediamine or phenylenediamine.

The third aspect of the present invention provides an MN₂O₂Use of carbon materials of units for the detection of nitric oxide, including but not limited to:

(1) detecting nitric oxide in exhaled breath of a human body;

(2) detection of nitric oxide in solution phase.

In order to make the technical solutions of the present invention more clearly understood by those skilled in the art, the technical solutions of the present invention will be described in detail below with reference to specific embodiments.

Example 1

1) Containing NiN₂O₂The preparation method of the unit carbon material comprises the following steps: ball milling 1 g of precursor M-Salen and 1 g of commercial acetylene black for 15 minutes by using a ball mill, calcining for 2 hours in a tubular furnace at 300 ℃ and introducing nitrogen airflow, after the tubular furnace is cooled to room temperature, washing the obtained black powder by using 30% hydrogen peroxide, deionized water and absolute ethyl alcohol, and then, washing at the temperatureDrying in a vacuum drying oven at 60 ℃ for 12 hours to obtain the NiN-containing₂O₂The yield of the unit carbon material is 56-80%.

FIG. 2 shows the NiN-containing material obtained in this example₂O₂The high-resolution electron microscope image of the unit carbon material shows that the material presents a cloud-like appearance, and the spherical aberration electron microscope image of the material is shown in FIG. 3, so that nickel atoms dispersed in a single atomic form can be clearly seen; fig. 4 is a diagram of the distribution of elements of the material, illustrating that elements such as Ni, N, O, C are uniformly distributed in the carbon material.

Example 2

1) Containing CuN₂O₂The preparation method of the unit carbon material comprises the following steps: ball-milling 1 g of precursor Cu-Salen and 1 g of graphene for 15 minutes by using a ball mill, calcining for 2 hours in a tubular furnace with nitrogen flow at 300 ℃, cooling the tubular furnace to room temperature, washing the obtained black powder by using 30% hydrogen peroxide, deionized water and absolute ethyl alcohol, and drying for 12 hours in a vacuum drying oven at 60 ℃ to obtain the product containing CuN₂O₂The yield of the unit carbon material is 56-80%.

Example 3

1) Containing CoN₂O₂The preparation method of the unit carbon material comprises the following steps: ball-milling 1 g of precursor Co-Salen and 1 g of commercial acetylene black for 15 minutes by using a ball mill, calcining for 2 hours in a 300-DEG C tube furnace with nitrogen flow, after the tube furnace is cooled to room temperature, washing the obtained black powder by using 30% hydrogen peroxide, deionized water and absolute ethyl alcohol, and drying for 12 hours in a vacuum drying oven at the temperature of 60 ℃ to obtain the powder containing the CoN₂O₂The yield of the unit carbon material is 56-80%.

Example 3

1) Containing CoN₂O₂The preparation method of the unit carbon material comprises the following steps: ball milling 1 g of precursor Co-Salen and 1 g of commercial acetylene black for 15 minutes by using a ball mill, calcining for 2 hours in a tube furnace with 900 ℃ introduced with nitrogen airflow, and after the tube furnace is cooled to room temperature, removing the obtained black powder by using 30% hydrogen peroxideWashing the seed water with absolute ethyl alcohol, and drying the washed seed water and absolute ethyl alcohol in a vacuum drying oven at the temperature of 60 ℃ for 12 hours to obtain the product containing CoN₂O₂The yield of the unit carbon material is 56-80%.

Example 4

1) Containing CoN₂O₂The preparation method of the unit carbon material comprises the following steps: ball-milling 1 g of precursor Co-Salen and 1 g of commercial acetylene black for 15 minutes by using a ball mill, calcining for 12 hours in a 900 ℃ tubular furnace with nitrogen flow, after the tubular furnace is cooled to room temperature, washing the obtained black powder by using 30% hydrogen peroxide, deionized water and absolute ethyl alcohol, and drying for 12 hours in a vacuum drying oven at the temperature of 60 ℃ to obtain the powder containing the CoN₂O₂The yield of the unit carbon material is 56-80%.

Example 5

1) Containing CoN₂O₂The preparation method of the unit carbon material comprises the following steps: ball-milling 10 g of precursor Co-Salen and 10 g of commercial acetylene black for 60 minutes by using a ball mill, calcining for 12 hours in a tube furnace with 900 ℃ introduced with nitrogen airflow, after the tube furnace is cooled to room temperature, washing the obtained black powder by using 30% hydrogen peroxide, deionized water and absolute ethyl alcohol, and drying for 12 hours in a vacuum drying oven with the temperature of 60 ℃ to obtain the powder containing the CoN₂O₂The yield of the unit carbon material is 56-80%.

Example 6

1) Containing FeN₂O₂The preparation method of the unit carbon material comprises the following steps: ball-milling 10 g of precursor Fe-Salen and 10 g of commercial acetylene black for 60 minutes by using a ball mill, calcining for 12 hours in a tube furnace with 900 ℃ introduced with nitrogen airflow, after the tube furnace is cooled to room temperature, washing the obtained black powder by using 30% hydrogen peroxide, deionized water and absolute ethyl alcohol, and drying for 12 hours in a vacuum drying oven with the temperature of 60 ℃ to obtain the FeN-containing material₂O₂The yield of the unit carbon material is 56-80%.

Example 7

1) Containing NiN₂O₂The preparation method of the unit carbon material comprises the following steps: 10 g of precursor NBall-milling i-Salen and 10 g of commercial acetylene black for 60 minutes by using a ball mill, calcining for 12 hours in a tube furnace with 900 ℃ introduced with nitrogen airflow, washing the obtained black powder with 30% hydrogen peroxide, deionized water and absolute ethyl alcohol after the tube furnace is cooled to room temperature, and drying for 12 hours in a vacuum drying oven with the temperature of 100 ℃ to obtain the NiN-containing powder₂O₂The yield of the unit carbon material is 56-80%.

And (3) performance testing:

(1) the detection method comprises the following steps:

electrochemical nitric oxide detection process: when detecting nitric oxide in solution phase, silver wire is selected as counter electrode, carbon is selected as counter electrode, and working electrode contains MN₂O₂A carbon material of the unit. The electrolyte was a deoxygenated PBS solution containing nitric oxide at various concentrations. The nitric oxide solution with different concentrations is detected by adopting a cyclic voltammetry method and a timing voltage method, wherein the test voltage range of the cyclic voltammetry technology is 0.1-1.1V, and the voltage value of the timing voltage is + 0.83V. The nitric oxide solution of saturated concentration was prepared from nitric oxide of 99.99% purity by passing it through a saturated deoxygenated PBS solution for 30 minutes. The initial concentration was 1.8mM, and other concentrations were obtained by dilution of 1.8mM of the initial solution. When the nitric oxide in the exhaled gas of the human body is detected, the collected nitric oxide samples with different concentrations are introduced into the PBS solution at the speed of 50mL/s, and the change of the current value is detected in real time.

(2) And (3) testing results:

1) the MN-containing compound prepared in example 1 was added₂O₂The unit carbon material shows better linearity in the nitric oxide concentration range of 10 nM-600 nM (as shown in FIG. 5) when applied to electrochemical detection of solution phase nitric oxide.

2) The MN-containing compound prepared in example 1 was added₂O₂When the unit carbon material is applied to the electrochemical method for detecting nitric oxide in human exhaled breath, the detection of nitric oxide can be detected at 8ppb (as shown in figure 6).

3) The precursor Ni-Salen prepared in example 1 and containing MN₂O₂The unit carbon material shouldWhen the method is used for electrochemically detecting nitric oxide of 8ppb in human exhaled breath, Ni-Salen basically has no response when the detection times reach 20 times, and MN is contained₂O₂The response value of the unit carbon material (Ni-SAS) is as high as 381.08 (shown in figure 7), and therefore, the MN is provided by the invention₂O₂The unit carbon material can have excellent detection sensitivity after being repeatedly used for many times according to the self-heterogeneous property.

4) The precursor Ni-Salen and NiN-containing precursor prepared in example 1 were added₂O₂When the unit carbon material is applied to electrochemical method for detecting nitric oxide in 1.8nM solution phase, Ni-Salen has no response, and NiN is contained₂O₂The unit carbon material shows obvious response peak (shown in figure 8), which shows that relative to the precursor Ni-Salen, the NiN-containing carbon material provided by the invention₂O₂The unit carbon material has higher detection sensitivity.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.