Adsorption performance and gas sensing of the Ru atomic catalyst on GaN sheets to transformer oil dissolved gases.

The Ru atomic catalyst-doped GaN (Ru-GaN) model was established by density functional theory (DFT), and the adsorption models of transformer oil dissolved gas (CO, H₂, CH₄, C₂H₂, C₂H₄ and C₂H₆) by a Ru-GaN monolayer were optimised. From the adsorption energy, differential charge density, electron state density, molecular orbital and desorption properties, the modification mechanism of Ru-GaN and the gas-sensitive response mechanism of Ru-GaN to CO, H₂, CH₄, C₂H₂, C₂H₄ and C₂H₆ were systematically studied. The introduction of metal Ru increases the defect state of GaN to provide the active site for the adsorption of gas molecules and reduces the adsorption barrier of GaN to gas molecules. The results show that Ru metal-doped GaN can adsorb CO, C₂H₂ and C₂H₄ by chemisorption, with E_ads of −2.068 eV, −2.422 eV and −1.877 eV and Q_t of −0.1696 e, −0.0671 e, −0.1222 e. In addition, charge redistribution leads to changes in the density of states, molecular orbitals and the conductivity of CO, C₂H₂ and C₂H₄ adsorption systems, indicating excellent gas sensitivity to the three gases. The desorption time further verified that Ru-GaN is an ideal CO and C₂H₂ gas scavenger and a recyclable material for C₂H₄ gas sensors. [ABSTRACT FROM AUTHOR]