First-Principles Investigation of Transition Metal (Co, Rh, and Ir)-Modified WS₂ Monolayer Membranes: Adsorption and Detection of SF₆ Decomposition Gases

Abstract

At high temperatures, the rapid and effective detection of SF 6 decomposition gas is a major challenge. Therefore, online detection of SF 6 decomposition gas at high temperatures for Gas Insulated Switchgear fault diagnosis is necessary. In this work, first-principles calculations are used to examine the adsorption and sensing properties of pristine WS 2 and transition metal Co, Rh, and Ir-modified WS 2 toward H 2 S, SO 2 , SOF 2 , and SO 2 F 2 . Our study delved into the adsorption energy and mechanisms of each system, exploring various aspects including adsorption energy, band gap, electron density, frontier orbital theory, conductivity, and recovery time. The findings indicate that the transition metal Co, Rh, and Irmodified WS 2 surface exhibits excellent adsorption capabilities for the decomposed gases. Co-WS 2 has good sensing performance for H 2 S, SO 2 , and SOF 2 and can achieve faster desorption for these three decomposed gases at high temperatures (598 K). SO 2 F 2 can be desorbed rapidly (0.65 s) from the surface of Rh-WS 2 at room temperature, and Rh-WS 2 has good selectivity for SO 2 F 2 . Interestingly, Ir-WS 2 remains difficult to desorb even at high temperatures for H 2 S (−2.642 eV), SO 2 (−2.260 eV), SOF 2 (−1.945 eV), and SO 2 F 2 (−2.841 eV) and can be used as a scavenger for these four gases. Therefore, the simulation experiments in this study aim to investigate the advantages of transition metal Co, Rh, and Ir-modified WS 2 for detecting SF 6 decomposition gases.