Yağmurcukardeş, MehmetSözen, YiğitBaşkurt, MehmetPeeters, François M.Şahin, Hasan2022-07-252022-07-2520222040-33642040-33642040-3372https://doi.org/10.1039/d1nr06534chttps://hdl.handle.net/11147/12194Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure) and Flemish Supercomputer Center (VSC). M. Y. was supported by a postdoctoral fellowship from the Flemish Science Foundation (FWO-Vl).The interface-dependent electronic, vibrational, piezoelectric, and optical properties of van der Waals heterobilayers, formed by buckled GeO (b-GeO) and Janus MoSO structures, are investigated by means of first-principles calculations. The electronic band dispersions show that O/Ge and S/O interface formations result in a type-II band alignment with direct and indirect band gaps, respectively. In contrast, O/O and S/Ge interfaces give rise to the formation of a type-I band alignment with an indirect band gap. By considering the Bethe-Salpeter equation (BSE) on top of G0W0 approximation, it is shown that different interfaces can be distinguished from each other by means of the optical absorption spectra as a consequence of the band alignments. Additionally, the low-and high-frequency regimes of the Raman spectra are also different for each interface type. The alignment of the individual dipoles, which is interface-dependent, either weakens or strengthens the net dipole of the heterobilayers and results in tunable piezoelectric coefficients. The results indicate that the possible heterobilayers of b-GeO/MoSO asymmetric structures possess various electronic, optical, and piezoelectric properties arising from the different interface formations and can be distinguished by means of various spectroscopic techniques.eninfo:eu-repo/semantics/embargoedAccessCalculationsEnergy gapLight absorptionGermanium compoundsArticle2-s2.0-8512358635610.1039/d1nr06534c