In this paper, the first-principles theory is used to explore the adsorption behavior of Ni catalyst decorated PtSe₂ (Ni-PtSe₂) monolayer toward the dissolved gas in transformer oil, namely CO and C₂H₂. Some Ni atoms from the catalyst are trapped in the Se vacancy on the pure PtSe₂ surface. The geometry configurations of Ni-PtSe₂ monolayer before and after gas adsorption, the electronic property of Ni-PtSe₂ monolayer upon gas adsorption, and the sensibility and recovery property of Ni-PtSe₂ monolayer are explored in this theoretical work. Through the simulation, the ${\mathrm{E}}_{\mathrm{ad}}$ of CO and C₂H₂ gas adsorption systems are calculated as −1.583 eV and −1.319 eV, respectively, both identified as chemisorption and implying the stronger performance of the Ni-PtSe₂ monolayer on CO molecule, which is further supported by the DOS and BS analysis. According to the formula, the sensitivity of Ni-PtSe₂ monolayer towards CO and C₂H₂ detection can reach up to 96.74% and 99.91% at room temperature (298 K), respectively, which manifests the favorable sensing property of these gases as a chemical resistance-type sensor. Recovery behavior indicates that the Ni-PtSe₂ monolayer is a satisfied gas scavenger upon the noxious gas dissolved in transformer oil, but its recovery time at room temperature is not satisfactory. To sum up, we monitor the status of the transformer to guarantee the stable operation of the power system through the Ni-PtSe₂ monolayer upon the detection of CO and C₂H₂, which may realize related applications, and provide the basis and reference to cutting-edge research in the field of electricity in the future.

The regular operation of transformers is significantly impacted by the insulation effectiveness of the transformer insulation oil–paper. In order to explore the mechanism of the influence of an electric field on the thermal decomposition performance of insulating oil–paper, this paper simulated the process of electrothermal coupling decomposition of insulating oil–paper from the micro-level based on molecular dynamics. It was determined that the insulating oil is made up of three 16-carbon hydrocarbon molecules, while the insulating paper is made up of 30 fibrous disaccharide molecules. Using the molecular dynamics simulation approach, the pyrolysis of the insulating oil and insulating paper under various electric field strengths was simulated, and the lysis of reactants and the distribution of products were statistically examined. This paper also studied how the electric field affected the microscopic process of the insulating oil–paper pyrolysis. The findings demonstrate that under the influence of electrothermal coupling, the big molecules of the insulating oil and insulating paper are pyrolyzed to produce a variety of tiny molecules. For the insulating oil, it is easily subject to electron displacement polarization under the influence of an external electric field since it contains non-polar molecules, especially impacted by an electric field of 100 V/m. For the insulating paper, its polar nature, on the other hand, makes itself a good candidate for guiding polarization when exposed to an external electric field. So, the greater the electric field strength is, the greater the impact on the thermal decomposition of the insulating paper is.

Molecular dynamics simulations have been used to study the thermomechanical properties of SrTiO₃/epoxy nanocomposites with different mass fractions. The calculation results revealed that thermal conductivity increased with mass fractions and temperature, which was consistent with the measured experiment value. Motion of molecular chain segment of pure epoxy resin became intense with temperature increase. With the increase in mass fractions of incorporated SrTiO₃ nanoparticles, the mobility of molecular chain segment was significantly weakened below 500 K compared with pure epoxy resin model and the model of nanocomposite with a mass fraction of 25 wt% SrTiO₃ showed best structure stability. Dipole autocorrelation functions (DACF) of pure epoxy resin fluctuated slightly under 350 K, but substantial fluctuation happened over 500 K. With the incorporation of SrTiO₃ nanoparticles, the fluctuation of DACF of nanocomposites decreased drastically, maintaining a small value of 0.004 Debye, which demonstrated that structure stability of nanocomposites was strengthened under 500 K. Based on interface model between epoxy resin macromolecular ligands and crystal plane (110) of SrTiO₃, interface interaction energy was calculated to be − 235.9 kcal/mol. To sum up, incorporation of SrTiO₃ nanoparticles could significantly improve the thermomechanical properties of epoxy resin and enhance structure stability of nanocomposites.