Two-dimensional FePc and MnPc monolayers as promising materials for SF6 decomposition gases detection: Insights from DFT calculations

Research on promising materials with good performance for detecting or removing the potent greenhouse gas sulfur hexafluoride (SF6) is critical for environmental preservation and human health. This study employed first-principles calculations to investigate the adsorption behavior and electronic properties of the four main SF6 characteristic decomposition components (H2S, SO2, SOF2 and SO2F2) on transition metal-doped phthalocyanine TMPc (TM = Fe, Mn) monolayers. Our results demonstrate that the monolayers are thermodynamically and dynamically stable. The analysis of the adsorption energy shows that the H2S, SO2, and SOF2 gas molecules are chemisorbed on the FePc monolayer, while the SO2F2 molecule is physisorbed by an O atom. The MnPc nano -sheet could regulate the adsorption ability of SO2 and SOF2 gas molecules, reaching an adsorption energy of-0.53 eV and-0.57 eV. The microcosmic mechanism of the gas-adsorbent interaction was revealed by analyzing the density of states, charge density difference, electron density distribution, and Hirshfeld charge. The monolayers were highly sensitive to H2S, SO2, SOF2, and SO2F2 because of the obvious changes in electrical conductivity and magnetism. The recovery time of MnPc toward SO2 and SOF2 gas molecules is 0.91 ms and 4.33 ms at room temperature. Our DFT calculations help to explore the chemical sensing application of TMPc monolayers in SF6 decomposition gas sensing.

Automated summary

This study investigates the adsorption behavior and electronic properties of transition metal-doped phthalocyanine monolayers on SF6 characteristic decomposition components using first-principles calculations. The results demonstrate that these monolayers are highly sensitive to H2S, SO2, SOF2, and SO2F2 and have short recovery times for SO2 and SOF2.