Design Of Triethylamine Gas-sensitive Materials And Study Of Their Sensitive Mechanis

As a common volatile organic compound（VOC）,triethylamine（TEA）is toxic,flammable and explosive and it is widely used in dyestuff,pesticide and pharmaceutical production.Excessive inhalation of triethylamine can cause respiratory burns.Gas sensors are urgent for efficient detection of triethylamine.However,the current triethylamine gas sensors are generally faced with the problems of low sensitivity,poor humidity resistance and unclear sensing mechanism.In recent years,composite nanostructures have attracted widespread attention due to the unique heterojunction interface and effective regulation of electronic structure and band structure.In this work,the sensitivity and humidity resistance have been improved obviously by reasonable structural design and defect engineering.Meanwhile sensing mechanism of triethylamine has also been explored in-depth.Several research results have been achieved mainly including:（1）Co₃O₄/NiO_x heterogeneous nanoparticles were prepared by atomic layer deposition strategy,and a large number of low coordination atoms were produced on the surface of Co₃O₄/NiO_x to regulate the oxygen vacancies.Compared with pure Co₃O₄,the sensitivity of Co₃O₄/NiO_x to triethylamine has been significantly improved.Through the characterization of XPS,EPR and UPS,it is confirmed that the enhanced sensing performance can be attributed to the effective modulation of the electronic structure and band structure by the oxygen vacancy in the heterostructure.（2）A three-dimensional ordered microporous ZrO₂ thin film was prepared by template method,and SnO₂ was deposited on ZrO₂ by atomic layer deposition.Based on the synergistic effect of ZrO₂ hydrophobic layer and SnO₂ sensitive layer,the SnO₂/ZrO₂showed ultrafast speed of response and recovery and great humidity resistance to triethylamine.The characterization of water contact angle proves that the humidity resistance is due to the inhibition of water adsorption by the hydrophobic air layer formed by the continuous 3DOM structure.（3）Carbon nanofibers（CNFs）were synthesized by polymerization,and then Co₃O₄ was anchored on the carbon nanofibers by hydrothermal method to form Co₃O₄/CNFs heterostructure.The sensing mechanism of triethylamine was elucidated by diffuse reflectance infrared Fourier transform spectroscopy and density functional theory calculation.It was revealed that the oxidation process of triethylamine includes molecular dissociation and oxidation.