Adsorption of Gas Molecules on Monolayer As/Sb Lateral Heterostructures Investigated by First Principles

Gas detection is already crucial for addressing an increasingly polluted environment. Due to its great advantages in terms of high carrier mobility, large specific surface area, and quick reaction, two-dimensional heterojunctions are widely used in high-performance gas sensor applications. In this study, two different types of LHSs (lateral heterostructures) based on As/Sb were built along armchair (AC) and zigzag (ZZ) interfaces, and the adsorption of gas molecules (NO2, NO, and NH3) on them was examined using first-principles calculations. The findings showed that NO2 molecules are chemically adsorbed on As/Sb LHSs, whereas NH3 molecules are physically adsorbed on As/Sb LHSs, NO molecules are physically at the AC interface, and chemically adsorbed at the ZZ interface.