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

• Published in: Applied surface science Vol. 608; p. 155119
• Main Authors: Nie, Zhifeng, Wang, Chen, Xue, Rou, Xie, Gang, Xiong, Huihui
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.01.2023
• Subjects: DFT computations; SF6 decomposition components; Surface adsorption; Transition metal phthalocyanine; Surface adsorption; SF6 decomposition components; Transition metal phthalocyanine; DFT computations
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2022.155119

[Display omitted] •The H2S, SO2, and SOF2 gas molecules are chemisorbed on the FePc monolayer.•MnPc monolayer shows appropriate capture ability for the SOF2 and SO2 molecules due to the hybridizations between Mn-d and S-sp orbitals.•The FePc and MnPc monolayers are highly sensitive to H2S, SO2, SOF2, and SO2F2.•The MnPc monolayer can be regarded as a recyclable gas sensor for SO2 and SOF2 detection. 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 nanosheet 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.