First-principles investigation on the optoelectronic characteristics of multilayer borophene

In this research, and photoelectric properties of two possible allotropes β₁₂-borophene and δ₆-borophene have been investigated using first-principles calculations for 1–4 borophene layers. The band structures, charge density, partial density of states, electrostatic potential and absorption spectra are calculated for multilayer borophene. The obtained results indicate that all layers exhibit anisotropic metallic behavior due to the interlayer charge transfer in β₁₂-borophene and δ₆-borophene. Furthermore, band splitting was increased with layer number, which was more pronounced in β₁₂-borophene. This finding was verified by the partial density of states. Moreover, the anisotropic structure of β₁₂-borophene and δ₆-borophene is evident in the calculated absorbance, which, while relatively low, distinctly exhibits a dependence on the number of layers. Meanwhile, multilayer borophene was almost transparent in visible region with weak absorption, which reflected its anisotropic structure. Density functional theory results suggested that multilayer borophene provided a critical basis for future research on photonic technology. These findings highlighted the substantial potential of multilayer borophene for photonic technology.