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CN-121990605-A - Tin dioxide/nitrogen-doped carbon composite material, preparation method thereof and application thereof in acetone sensor

CN121990605ACN 121990605 ACN121990605 ACN 121990605ACN-121990605-A

Abstract

The application provides a tin dioxide/nitrogen-doped carbon composite material, a preparation method thereof and application thereof in an acetone sensor, and belongs to the technical field of gas sensitive materials. The composite material is of a porous honeycomb structure with tin dioxide nano particles dispersed and embedded in a nitrogen-doped carbon matrix, an X-ray diffraction crystal face is a tin dioxide rutile structure crystal face, and the molar ratio of the tin dioxide nano particles to the nitrogen-doped carbon matrix is (0.5-1.5) (1-3). When the tin dioxide/nitrogen-doped carbon composite material provided by the application is applied to a gas sensor, the tin dioxide/nitrogen-doped carbon composite material has excellent sensing performance, good selectivity and sensitivity to acetone gas, and excellent repeatability, can be used as an ultrasensitive sensing platform for detecting diabetes biomarkers in expiration in real time, and has great potential in early diagnosis and screening of diabetes.

Inventors

  • GUO RUIHUA
  • ZHU XIAOFENG
  • LI YONGZHEN
  • DONG LIHUA
  • ZHANG YING
  • LI PENG
  • YU YUE

Assignees

  • 北京市科学技术研究院

Dates

Publication Date
20260508
Application Date
20251231

Claims (10)

  1. 1. A tin dioxide/nitrogen-doped carbon composite material is characterized in that the composite material is of a porous honeycomb structure in which tin dioxide nano particles are dispersed and embedded in a nitrogen-doped carbon matrix, an X-ray diffraction crystal face is a tin dioxide rutile structure crystal face, and the molar ratio of the tin dioxide nano particles to the nitrogen-doped carbon matrix is (0.5-1.5): 1-3.
  2. 2. The tin dioxide/nitrogen-doped carbon composite according to claim 1, wherein the nitrogen-doped carbon matrix is derived from ethylenediamine tetraacetic acid.
  3. 3. A method for preparing a tin dioxide/nitrogen doped carbon composite material according to claim 1 or 2, comprising the steps of: And dissolving tin salt, ethylenediamine tetraacetic acid and an inorganic salt template agent in a solvent, fully mixing to obtain a mixture, freeze-drying the mixture, and calcining the mixture at the temperature of 450-550 ℃ in an air atmosphere to obtain the tin dioxide/nitrogen-doped carbon composite material.
  4. 4. The method according to claim 3, wherein the tin ion is tetravalent tin or divalent tin, and/or the tin salt is selected from the group consisting of chloride, sulfate, nitrate, nitrite, and organic acid salt of tin.
  5. 5. A process according to claim 3, wherein the inorganic salt templating agent is selected from sodium or potassium salts and/or the solvent is water.
  6. 6. The method according to claim 3, wherein the condition of sufficient mixing is magnetic stirring at room temperature for 20-60 min, and/or the calcination is carried out for 2-5 h, and/or the step of freeze-drying comprises freeze-drying at-80 ℃ for 12-80 h.
  7. 7. A method of preparing according to claim 3, further comprising a post-treatment step of washing, drying after calcination.
  8. 8. Use of the tin dioxide/nitrogen-doped carbon composite material according to claim 1 or 2, or the tin dioxide/nitrogen-doped carbon composite material obtained by the method according to any one of claims 3 to 7, for the preparation of an acetone gas concentration detection product, or a medical product for early diagnosis and screening of diabetes.
  9. 9. The use according to claim 8, wherein the operating temperature of the tin dioxide/nitrogen doped carbon composite in the product is 260-350 ℃.
  10. 10. An acetone sensor, characterized in that the gas sensitive material in the acetone sensor comprises the tin dioxide/nitrogen doped carbon composite material according to claim 1 or 2, or the tin dioxide/nitrogen doped carbon composite material obtained by the method according to any one of claims 3-7.

Description

Tin dioxide/nitrogen-doped carbon composite material, preparation method thereof and application thereof in acetone sensor Technical Field The invention belongs to the technical field of gas-sensitive materials, and particularly relates to a tin dioxide/nitrogen-doped carbon composite material, a preparation method thereof and application thereof in an acetone sensor. Background The research shows that the content of acetone in the exhaled gas of the diabetics is obviously higher, wherein the concentration of the acetone in the exhaled gas of the diabetics is more than 1.8 ppm, and the healthy people only have 300-900 ppb. Therefore, the acetone content in the human expiration is used as a detection marker, and the detection marker provides possibility for realizing noninvasive diagnosis and screening of early diabetes. However, since the composition of the exhaled gas of the human body is complicated and the volatility of acetone is strong, an acetone sensor applied to the auxiliary diagnosis of diabetes needs more excellent sensing performance, good selectivity and sensitivity than a general gas sensor. The prior art provides some materials with acetone gas adsorptivity, such as the patents CN106872533A, CN103730638a and CN120888900a, etc., however, the performance of the materials provided by the above scheme and the acetone gas sensors currently on the market still needs to be improved. Disclosure of Invention In order to solve the above problems, the present application aims to provide an acetone gas-sensitive material having excellent sensitivity, response rate and structural stability, so that it is more suitable for noninvasive screening and auxiliary diagnosis in early stages of diabetes. On one hand, the application provides a tin dioxide/nitrogen-doped carbon composite material, which is a porous honeycomb structure in which tin dioxide nano particles are dispersed and embedded in a nitrogen-doped carbon matrix, wherein an X-ray diffraction crystal face is a tin dioxide rutile structure crystal face, and the molar ratio of the tin dioxide nano particles to the nitrogen-doped carbon matrix is (0.5-1.5) (1-3). Wherein, all XRD diffraction peaks of the composite material correspond to (110), (101), (200), (111), (210), (211), (220), (002), (310), (112), (301), (202) and (321) crystal planes (JCPDS card No. 88-0287) of a SnO 2 rutile structure (tetragonal system). In one embodiment, the nitrogen-doped carbon matrix is derived from ethylenediamine tetraacetic acid. Wherein, ethylenediamine tetraacetic acid (EDTA) is used as a precursor of a nitrogen-doped carbon skeleton and a chelating agent, and the composite material provided by the application has multiple advantages, such as having the functions of nitrogen source and carbon source, wherein EDTA molecules contain abundant carbon and nitrogen, Oxygen can be used as a carbon source and a nitrogen source simultaneously during high-temperature pyrolysis, so that nitrogen doping of a carbon skeleton is realized, amorphous nitrogen doped carbon (NC) is formed, the synthesis step is simplified, the cost is reduced, and the introduction of an additional nitrogen source is avoided; the chelating coordination function can be used as a strong chelating agent to form a stable complex with Sn 4+, effectively prevent SnCl 4 from hydrolyzing or agglomerating in a solution, ensure that SnO 2 nano particles are uniformly distributed in a nitrogen-doped carbon skeleton in the subsequent pyrolysis process, avoid local aggregation of active substances, improve the uniformity and the active site density of the material, and optimize the gas-sensitive performance of the material; the formation of a three-dimensional porous structure is promoted, the synergistic effect of EDTA and a salt template induces the formation of the three-dimensional porous structure in the freeze drying process, wherein gas (such as CO 2、NH3) generated by EDTA decomposition further etches a carbon skeleton to form a microporous-mesoporous-macroporous coexisting porous system, the structure remarkably improves the specific surface area of the material (SEM shows that the pore size covers nano-scale to submicron-scale) and provides rich adsorption sites and rapid diffusion channels for gas molecules, the formation of an amorphous carbon skeleton is that carbon generated by EDTA pyrolysis exists in an amorphous form, the conductivity is enhanced, the surface active sites are provided, the electron transmission is promoted, the gas-sensitive response speed is improved, the nitrogen doping form is diversified, the nitrogen doping form contains various nitrogen forms such as graphite nitrogen, pyridine nitrogen and the like, the graphite nitrogen enhances the conductivity, the pyridine nitrogen enhances the gas adsorption activity, the gas-sensitive performance is synergistically enhanced, the structural stability is synergistically enhanced, the EDTA-derived nitrogen-doped carbon skeleton is not