Gas sensing potential of monolayer MoB: A first principles study

Abstract

Monolayer MoB is one of MBenes with a structure similar to graphene. Through first-principles calculations, we have investigated the adsorption characteristics of monolayer MoB for CO, NO, SO, SO2 gases. The results show that CO and NO tend to adsorb at the top of Mo, and SO and SO2 tend to adsorb at the top of B. The adsorption energies of all gas molecules are negative, with the smallest adsorption energy for SO. All gas molecules are charge acceptors, with SO2/MoB having the largest charge transfer value of 0.977 eV. According to the transition state theory, the shortest recovery time for monolayer MoB adsorbed CO molecule. This means that the process of CO adsorption by monolayer MoB is reversible and monolayer MoB has the potential to be used as a CO gas detection sensor. At room temperature, it is almost impossible for monolayer MoB to recover its initial state after adsorption of NO, SO and SO2. In addition, MoB has high sensitivity in detecting NO, SO and SO2 due to its low adsorption energy for NO, SO and SO2, and has the potential to be a sensitive irreversible detection sensor for detecting NO, SO and SO2.