In this work, we investigated the adsorption mechanism of acetone and toluene on the surface of silicene by the quantum simulation method. The images of the potential energy surfaces for different positions of the adsorbate on the silicene surface were explored by Computational DFT-based Nanoscope tool for determination of the most stable configurations and diffusion possibilities. The charge transfer in order of 0.2 – 0.3 electrons and the tunneling gap opening of 18 – 23 meV due to acetone and toluene, respectively, suggest that silicene is considerably sensitive with these VOCs and can be used as the material in the fabrication of reusable VOC sensors.

Borophene, a new member of the 2D material family, was proven theoretically and empirically in many recent studies that it has a unique structure and promising properties applied in batteries and electronic devices. In this work, the adsorbability of β12 – borophene towards some main poisonous gases was investigated. Herein, first-principle calculations were employed to obtain the adsorption configurations, adsorption energy of CO, NO, CO2, NH3, and NO2 on b12 – borophene by using three van der Waals correlation functionals: revPBE-vdW, optPBE-vdW, and vdW-DF2. Also, the most stable configurations and diffusion possibilities of the gas molecules on the surface of b12 – borophene were determined visually by using Computational DFT-based Nanoscope. The nature of bonding and interaction between gas molecules and b12 – borophene were disclosed by using the density of states analysis and Bader charge analysis. Remarkably, borophene exhibits as a highly selective adsorbent when having great interactions with NOx gases outweigh the others.

The adsorption mechanism of 2-butanone (ethyl methyl ketone) on the surface of graphene is investigated by using Density Functionals Theory (DFT). A 2-butanone molecule is chosen as a selected example of main volatile organic compounds (VOCs) in exhaled breath. To describe the absorption of 2-butanone and graphene substrate, we have performed DFT simulations including van de Waals (vdW) interactions implemented in the Vienna Ab-initio Simulation Package (VASP). The global minimum energy configurations and binding energies for a 2-butanone molecule adsorbed on graphene are determined by using Computational DFT-based Nanoscope tool for imaging the binding possibility of the adsorbed molecules on the graphene surface. The adsorption energy profiles are calculated by three functionals of van der Waals interactions: revPBE-vdW, optPBE-vdW, and vdW-DF2. It is shown that the adsorption energy is highly sensitive to the vdW functionals. The fundamental insights of the interactions between 2-butanone and graphene through molecular doping, i.e., charge transfer are discussed in detail.

In this work, we investigate the defect structure of Silicene with a vancacy and the adsorption mechanism of isopropanol on the surface of defected Silicene by employing the Density Functional Theory method. The adsorption profile was determined based on van der Waals functional optPBE-vdW and the charge transfer between isopropanol and silicene this system was also calculated by Bader charge analysis method. In the defected Silicene, Si vacancy preferably forms on the lower layer of the bulking structure. As a Si vacancy is introduced, Silicene exhibits a metallic behavior with zero bandgap. Due to the losing electron of defected Silicene, isopropanol is adsorbed on the surface with the most favourable adsorption configuration in which oxygen atom towards the surface of Silicene. Isopropanol adsorption opens a tunnelling gap of defected Silicence, resulting in the mili-gap characteristics of the adsorbed Silicene system. The adsorption profile of this volatile organic compound on defected Silicene implies the physics adsorption characteristics. The adsorption energy for isopropanol was found to be -0.40 eV. In addition, the charge transfer of 0.24 electron was obtained