DFT+U study of sulfur hexafluoride decomposition components adsorbed on ceria (110) surface.

• Adsorption properties of SF6 decomposition components on ceria surface were compared based on DFT calculations. • Adsorption of H 2 S, SO 2 and SOF 2 cause conspicuous charge redistribution on CeO 2 (110) surface. • CeO 2 (110) shows higher sensitivity to H 2 S, SO 2 and SOF 2 in comparison with SF 6. The detection of sulfur hexafluoride (SF 6) decomposition components is significant for monitoring the conditions of SF 6 -gas-insulated equipment. In present study, the adsorption of SF 6 and its decomposition components (H 2 S, SO 2 , SOF 2 , and SO 2 F 2) on ceria (110) was investigated by performing calculations based on density functional theory (DFT). Adsorption energy, adsorption configuration, charge transfer, density of states, potential energy and work function for molecular adsorption were adopted to evaluate the performance of ceria (110) on sensing SF 6 decomposition components. Among all the gas molecules, H 2 S, SO 2 and SOF 2 were chemically adsorbed on ceria surface with the adsorption energy following the order: SOF 2 > SO 2 > H 2 S, while SO 2 F 2 and SF 6 were physically adsorbed on the substrate. Besides, the amount of charge transfer and work function modification of H 2 S, SO 2 and SOF 2 molecule's adsorption were larger than those of SO 2 F 2 and SF 6. These calculation results demonstrated ceria (110) showed prominent sensitivity to H 2 S, SO 2 and SOF 2 while less activity to SF 6 , which means sensor based on ceria is promising for detecting H 2 S, SO 2 and SOF 2 in SF 6 gas background, and thus has the potential to online monitor the working condition of SF 6 -gas-insulated equipment. [ABSTRACT FROM AUTHOR]