Nonmetallic Atom Regulation for Enhanced NiPr Monolayer Sensing of SF 6 Decomposition Gases: A DFT Study

High Resolution Image Download MS PowerPoint Slide The identification and mitigation of SF 6 decomposition gases (SO 2, H 2 S, HF, SOF 2, and SO 2 F 2 ) are critical for environmental protection and human health. In this study, we utilized density functional theory (DFT) to systematically investigate the adsorption characteristics and sensing properties of these gases on pristine nickel-porphyrin (NiPr) and nonmetal-atom-modified nickel-porphyrin (NiNPr, N = B/O) monolayers. The studied results indicate that the NiPr monolayer is not suitable as a gas-sensitive material for the detection of SF 6 decomposition gas molecules due to its weak adsorption ability and low sensitivity. However, the incorporation of nonmetallic B and O atoms into the NiPr monolayer significantly enhances the binding energy, ensuring the structural stability of the resulting NiBPr and NiOPr monolayers. The bandgap values of these doped monolayers are reduced to 0.326 eV (NiBPr) and 0.057 eV (NiOPr) compared to 0.985 eV for the pristine NiPr monolayer. Notably, the NiBPr and NiOPr monolayers demonstrate enhanced adsorption energy for SO 2, H 2 S, SOF 2, and HF gases (−0.56 eV to −1.08 eV), indicating chemical adsorption. A comprehensive analysis of the total electron density distribution, charge density difference, and density of states was conducted to elucidate the interaction mechanisms between the gases and the monolayers. Additionally, significant changes in work function and bandgap values confirm the high sensitivity of these monolayers. Recovery time assessments for gases including SO 2, H 2 S, HF, SOF 2, and SO 2 F 2 reveal that the NiBPr monolayer is viable as a reusable gas sensor for SO 2, H 2 S, HF, and SOF 2, while the NiOPr monolayer is apt for sensing H 2 S, HF, and SOF 2 gases. These findings are significant in highlighting the potential of NiBPr and NiOPr monolayers as innovative sensors for the SF 6 decomposition gases.