Adsorption of Acetone and Toluene on Single-Vacancy Silicene by Density Functional Theory Calculations

Abstract

In this work, we investigated the adsorption mechanism of acetone and toluene on the surface of single-vacancy silicene by Density Functional Theory method with taking into account the van der Waals interaction via the optPBE-vdW functional. The potential energy surface and adsorption energy profile are obtained by using the Computational DFT–based Nanoscope tool. It is found that acetone prefers an inclined configuration while toluene favors the parallel one towards the substrate. The single-vacancy silicene maintains its metallic electronic structure after adsorption. The adsorption energies for acetone and toluene adsorptions are −0.36 eV and −0.57 eV, respectively. The Bader charge analysis shows a charge transfer of 0.17e and 0.30e for adsorption of acetone and toluene on silicene, respectively.

Adsorption energy profiles of the acetone (a) and Charge density difference in side view of the acetone (b).