Evaluating the electronic sensitivity of pristine, B, and Si doped graphyne to methanol: DFT study

Abstract

The reactivity and electronic sensitivity of pristine, B-doped graphyne (BG) and Si-doped graphyne (SiG) sheet toward the methanol gas adsorption were explored by calculation of density functional theory. It was discovered that the pristine graphyne unstably adsorbs the methanol gas with a −6.28 kcal mol−1 adsorption strength. Also, the evaluated electronic properties of pristine graphyne are not sensitive toward methanol gas. The doping process improves neither the reactivity nor sensitivity of graphyne to methanol, while the Si-doping enhances the reactivity and has a significant impact on the sensitivity. The HOMO-LUMO gap of SiG considerably reduces from 2.59 to 2.04 eV via methanol adsorption, increasing the electrical conductivity. It indicates that the SiG sheet may be a promising electronic sensor for methanol detection, unlike the BG and pristine graphyne. Also, the adsorption of methanol on the SiG largely affects its work function which significantly alters the field emission electron current from its surface, demonstrating that it might also be a working function form of methanol detection sensor. The SiG sheet benefits from a quick recovery time of 1.38 ms for desorption of methanol.