Adsorption properties of N2O and NF3 on γ-Al2O3 (110) surface: A DFT study

Abstract

To alleviate the environmental pressure caused by SF6 emissions, SF6/N2 has been widely used in power systems as a replacement gas. In case of abnormal equipment failure, SF6/N2 will decompose and produce many kinds of toxic and harmful gases, so it is necessary to place molecular sieves to safeguard the insulation performance of the equipment. Since γ-Al2O3 is the main component of molecular sieves, the adsorption of N2O and NF3 on the surface of γ-Al2O3 (110) is systematically calculated in this paper using density functional theory to investigate the adsorption energy, charge transfer, density of states (DOS), electrons density difference (EDD), electron localization function (ELF) and frontier molecular orbital theory for their stable configurations. The calculated results show that although N2O adsorption on γ-Al2O3 (110) is slightly stronger than NF3, both gases have weak interactions with γ-Al2O3 (110) and thus may both be physisorbed. This paper deepens the basic understanding of adsorbent adsorption of SF6/N2 decomposition gases in power equipment, and provides a theoretical basis for the optimisation study of adsorbents required for equipment with SF6/N2 as the insulating medium.