AlC3 3 monolayer: Highly responsive and selective gas sensing material for SF6 6 decomposed gases (SOF2, 2, SO2F2 2 F 2 and SO2) 2 )

Sulfur hexafluoride (SF6) 6 ) is widely employed in industrial applications due to its interesting insulating properties. However, under electrical discharge conditions, it can undergo decomposition, yielding hazardous gases such as SOF2, 2 , SO2F2, 2 F 2 , and SO2, 2 , which can pose significant risks due to their increased toxicity and corrosive nature, affecting human health, the environment, and equipments. In this investigation, we employed density functional theory and ab-initio molecular dynamics to evaluate the stability of AlC3 3 monolayer and investigate its sensing capabilities. The findings establish the AlC3 3 monolayer as a champion material for detecting SF6 6 decomposition gases, specifically SOF2, 2 , SO2F2, 2 F 2 , and SO2. 2 . Importantly, the AlC3 3 monolayer exhibited low sensitivity to humidity and other gases, including CO2, 2 , CO, HF, H2, 2 , HCN, and H2S, 2 S, highlighting its exceptional selectivity. SO2F2 2 F 2 exhibited the substantial adsorption energy of-1.36 eV, a work function of 5.2 eV, and a-0.69e charge transfer. Similarly, SO2 2 and SOF2 2 displayed significant adsorption energy (-1.19 eV and-1.08 eV, respectively), work functions (4.55 eV and 4.81 eV), and charge transfers (-0.61e and 0.78e). The significant variation in work function upon SO2F2 2 F 2 adsorption indicates the AlC3 3 monolayer's potential selectivity for SO2F2 2 F 2 over SO2 2 and SOF2, 2 , making it a promising material for surface work function modulated transistors. Ab-initio molecular dynamics simulations confirm AlC3 3 monolayer stability after adsorption at 300 K, validating predicted positions by density functional theory.