Degradation of molecular gases on porous CNPs/CuO composite nanostructures

   Purpose. Study of electrocatalytic activity of porous composite nanofilms CNPs/CuO, causing degradation of molecular gases.

   Methods. The research methods included the use of a specially designed experimental setup consisting of a glass chamber with a closed-loop air flow system, a blower to generate a constant air flow, and an air filter with composite electrocatalytic nanofilms. During the experiment, isopropyl alcohol and butyl acetate were added dropwise to the chamber. The vapors of these substances, evaporating under the influence of the air flow, passed through the composite filter. The degradation efficiency of volatile organic compounds was recorded in real time using a gas sensor, and in certain series of experiments, Fourier transform infrared (FTIR) spectral analysis was additionally performed to study the processes occurring in the system in more detail.

   The study results demonstrate the high efficiency of the electrocatalytic decomposition of volatile organic compounds on CNPs/CuO composite coatings. Applied electrical voltage initiates the formation of electron-hole pairs, which, by interacting with water and oxygen molecules, generate reactive oxygen species (OH, O₂^-), ensuring the complete mineralization of isopropyl alcohol and butyl acetate to CO₂ and H₂O. Fourier transform IR spectroscopy revealed the absence of characteristic absorption bands of the starting compounds and the appearance of signals from the reaction
products.

   Conclusion. According to the results of FTIR spectroscopy, the passage of high-molecular gases such as isopropyl alcohol and butyl acetate through an air filter with CNPs/CuO composite films with applied electric voltage (9V, 17V) leads to their complete decomposition into CO₂ and H₂O due to electrocatalytic processes occurring on the surface of the synthesized films.

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