Prediction of two-dimensional AlBrSe monolayer as a highly efficient photocatalytic for water splitting

The effect of biaxial strain on the electronic and optical properties of orthorhombic two-dimensional AlBrSe monolayer was investigated by the first-principles calculations. Stability analyses by phonon dispersion curve and molecular dynamics simulation indicate that the AlBrSe monolayer is mechanically and thermodynamically stable with no negative frequencies. It is found that the monolayer AlBrSe is an indirect bandgap semiconductor of 1.654 eV/2.231 eV using PBE and HSE06 methods, respectively. The maximum value of the absorption coefficient lies in the ultraviolet region while in the visible region the absorption coefficient is 6.14 × 103 cm−1 at the photon energy of 3.13 eV. The results reveal that the biaxial strain engineering may be a powerful tool for modifying the optoelectronic characteristics of the AlBrSe monolayer. Furthermore, our findings show a drastic shift in the bandgaps from indirect to direct bandgap at some tensile strains (4% and 6%). Moreover, the use of AlBrSe monolayer in innovative energy systems has a bright future as a promising candidate for photocatalytic water-splitting.