Adsorption of toxic gases on silicene/Ag(111). Issue 32 (14th June 2019)

• Record Type: Journal Article
• Authors: Osborne, Dale A.; Morishita, Tetsuya; Tawfik, Sherif Abdulkader; Yayama, Tomoe; Spencer, Michelle J. S.
• Is Part Of: Physical chemistry chemical physics. Volume 21:Issue 32(2019)
• Page Start: 17521
• Page End: 17537
• Publication Date: 2019-06-14
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp01901d
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Silicene/Ag(111) demonstrates many unique properties, and shows potential in sensing and storage applications of toxic gases such as SO2, NO2 and H2 S. Abstract : Silicene is a two-dimensional nanomaterial, composed of Si atoms arranged into a buckled honeycomb network. It has become of great interest in recent years due to its remarkable properties such as its natural compatibility with current silicon-based technology. Due to its extreme thinness on the nanoscale, and large lateral dimensions, it has potential applications in gas sensing, gas storage and components in modern electronic devices. In this work, density functional theory calculations and ab initio molecular dynamics simulations are used to examine the reaction of SO2, NO2 and H2 S on the Si/Ag(111) surface. It was shown that each gas will adsorb on the surface in different orientations and adsorption sites. SO2 and NO2 were found to chemisorb on the surface, whereas H2 S was found to physisorb. SO2 and H2 S adsorb associatively, whereas NO2 readily dissociates, producing adsorbed oxygen, and gaseous NO. At elevated temperatures, the SO2 and NO2 remain strongly bound to the surface, resulting in poisoning of the silicene, while H2 S readily desorbs. Ab initio molecular dynamics also show that NO2 will selectively bind before SO2 when both gases are present in the same environment. This work shows that Si/Ag(111) may provide useful properties for gas sensing and storage applications.