Electronic structures and optical properties of Janus GeXY (X, Y = P, As and Sb): First-principles predictions

Abstract

The electronic structures and optical properties of three Janus materials (GeAsP, GeSbP, and GeAsSb) have been systematically investigated using first-principles density functional calculations. These monolayers are dynamically and thermodynamically stable. The indirect bandgap is discovered in these monolayer materials, and excellent optical absorption is also exhibited with coefficients of up to 3.4 × 105 cm−1. Furthermore, uniaxial strain induced can enhance their optical absorption coefficient significantly and regulate their band edge position, providing oxidation-reduction conditions of photocatalytic water splitting. These Janus materials may become one of the outstanding candidates in the fields of photovoltaics and photocatalysis with promising applications.