Adsorption of SF6 Decomposition Components on Pt-Doped Graphyne Monolayer: A DFT Study

To propose a novel type of sensing material applied in the field of sulfur hexafluoride (SF
₆
) insulated gas, we investigated the adsorption performance of SF
₆
decomposed species (H
₂
S, SO
₂
, and SOF
₂
) on Pt-doped graphyne (GD) monolayer. We initially studied the possible stable structure of Pt–GD monolayer and found that the Pt dopant preferred adsorption onto the
$\text{C}\equiv \text{C}$
bond. We further investigated electronic differential density, band structure, and density of states to evaluate the chemical and physical interactions between Pt–GD and four typical gases, namely, H
₂
S, SO
₂
, SOF
₂
, and SF
₆
. The results indicated that only H
₂
S, SO
₂
, and SOF
₂
molecules were adsorbed onto the Pt–GD with strong chemical interactions due to the large adsorption energy, evident electronic differential density change, and orbital hybridization. These results showed that the strong interactions were caused by the Pt dopant. The conductivity of monolayer was enhanced by H
₂
S but was weakened by SO
₂
and SOF
₂
. The adsorption capacity occurred in the following order: SO
₂
> H
₂
S > SOF
₂
> SF
₆
. Our work determined the stable Pt doping structure on GD and provided theoretical support for a novel material realizing the operation state evaluation of SF
₆
insulated gas equipment.