A molecular modeling on the boron trichloride gas detection by S- and Cr-doped graphyne

Here, we scrutinize the adsorption of boron trichloride (BCl₃) on pure, S-doped, and Cr-doped graphyne by means of density functional theory (DFT) calculations. BCl₃ interacts weakly with pure graphyne, so it cannot be employed as a sensor. Despite the strengthening of interaction through S-doping, we cannot still employ the S-doped sheet as a sensor. Nevertheless, there is a considerable increase in the sensitivity and reactivity of the sheet through substituting the transition metal Cr for the C. There is a reduction in the HOMO-LUMO gap of Cr-doped graphyne from 2.18 to 1.38 eV when BCl₃ is adsorbed, thereby increasing the electrical conductivity to a great extent. Hence, it is possible to convert the considerable change in conductivity into an electronic signal, which demonstrates the encouraging nature of Cr-doped graphyne as a sensor to detect BCl₃. Additionally, the adsorption process reduces the work function of graphyne to a great extent, which demonstrates that we can also employ it as a work function-type sensor for detecting BCl₃.