Novel Polymorph of GaSe. (2nd September 2021)

• Record Type: Journal Article
• Authors: Grzonka, Justyna; Claro, Marcel S.; Molina‐Sánchez, Alejandro; Sadewasser, Sascha; Ferreira, Paulo J.
• Is Part Of: Advanced functional materials. Volume 31:Number 48(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-02
• Subjects: 2D materials -- GaSe -- III‐VI semiconductors -- molecular beam epitaxy -- post‐transition metal chalcogenides -- scanning transmission electron microscopy -- van der Waals structures; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202104965
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: 2D GaSe is a semiconductor belonging to the group of post‐transition metal chalcogenides with great potential for advanced optoelectronic applications. The weak interlayer interaction in multilayer 2D materials allows the formation of several polymorphs. Here, the first structural observation of a new GaSe polymorph is reported, characterized by a distinct atomic configuration with a centrosymmetric monolayer (D3d point group). The atomic structure of this new GaSe polymorph is determined by aberration‐corrected scanning transmission electron microscopy. Density‐functional theory calculations verify the structural stability of this polymorph. Furthermore, the band structure and Raman intensities are calculated, predicting slight differences to the currently known polymorphs. In addition, the occurrence of layer rotations, interlayer relative orientations, as well as translation shear faults is discussed. The experimental confirmation of the new GaSe polymorph indicates the importance of investigating changes in the crystal structure, which can further impact the properties of this family of compounds. Abstract : The observation of a new GaSe polymorph is reported, obtained by molecular beam epitaxy growth, with a cs‐TL (D3d ). In particular, they show a comprehensive characterization of the atomic structure of this GaSe polymorph by aberration corrected scanning transmission electron microscopy. Moreover, the stability of this polymorph is verified by density functional theory calculations, from which the band structure and Raman intensities are predicted.