Pd-Adsorbed SiN₃ Monolayer as a Promising Gas Scavenger for SF₆ Partial Discharge Decomposition Components: Insights...

Gas-insulated switchgear (GIS) equipment must be protected by detecting and eliminating the toxic SF₆ partial discharge decomposition components. This study employs first-principles calculations to thoroughly investigate the interaction between a Pd-adsorbed SiN₃ monolayer (Pd-SiN₃) and four typical SF₆ decomposition gases (H₂S, SO₂, SOF₂, and SO₂F₂). The study also investigates the associated geometric, electrical, and optical characteristics along with the sensing sensitivity and desorption efficiency. The ab initio molecular dynamics (AIMD) simulations demonstrated the favorable stability of the Pd-SiN₃ monolayer. Furthermore, the Pd-SiN₃ monolayer exhibited strong chemisorption behavior toward H₂S, SO₂, SOF₂, and SO₂F₂ gases because of the higher adsorption energies of -2.717, -2.917, -2.457, and -2.025 eV, respectively. Furthermore, significant changes occur in the electronic and optical characteristics of the Pd-SiN₃ monolayer following the adsorption of these gases, resulting in remarkable sensitivity of the Pd-SiN₃ monolayer in relation to electrical conductivity and optical absorption. Meanwhile, all of these gas adsorption systems exhibited extremely long recovery times. The aforementioned theoretical findings suggest that the Pd-SiN₃ monolayer has the potential to be an effective gas scavenger for the storage or removal of the SF₆ decomposition components. Additionally, it might function as a reliable one-time sensor for detecting these gases. The results potentially provide valuable theoretical guidance for maintaining the normal operation of the SF₆ insulation devices.