Li-decorated borophene–graphene heterostructure under gas adsorption

Two-dimensional materials show great application potentials in gas sensor due to its high surface-to-volume ratio. In this regard, we investigate the adsorption energies of five gases: NH3, NO, NO2, H2S, and SO2, on borophene, with the help of the density functional theory (DFT). The results show the high adsorption capacity of borophene, but gas adsorption can lead to its structural instability with the greatest influence of nitrogen. However, the heterostructure of borophene and graphene (B/G) can inhibit the deformation and optimize the adsorption capacity of borophene. In order to enhance the adsorption of gas molecules on B/G, lithium is doped in the borophene layer, and it shows that the adsorption of sulfur gas can be significantly enhanced. In addition, the transport properties of Li-decorated B/G inhibitors are simulated by non-equilibrium Green’s function method. The graphene composite and Li doping are found to have a great impact on the gas-sensitive properties of borophene, which provides new ideas for the application of borophene in sensors.