Universal Zigzag Edge Reconstruction of an α-Phase Puckered Monolayer and Its Resulting Robust Spatial Charge Separation

Yanxue Zhang; Yanyan Zhao; Yizhen Bai; Junfeng Gao; Jijun Zhao; Yong-Wei Zhang

doi:10.1021/acs.nanolett.1c02461

Universal Zigzag Edge Reconstruction of an α-Phase Puckered Monolayer and Its Resulting Robust Spatial Charge Separation

Nano Lett. 2021 Oct 13;21(19):8095-8102. doi: 10.1021/acs.nanolett.1c02461. Epub 2021 Sep 10.

Authors

Yanxue Zhang¹, Yanyan Zhao¹, Yizhen Bai¹, Junfeng Gao¹, Jijun Zhao¹, Yong-Wei Zhang²

Affiliations

¹ Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China.
² Institute of High Performance Computing, A*STAR, 138632 Singapore.

PMID: 34505776
DOI: 10.1021/acs.nanolett.1c02461

Abstract

Edges are important, because they dictate the stability and properties of nanoribbons. Here, we reveal a universal reconstruction of the ZZ edge into a (2 × 1) tubed [ZZ(Tube)] edge, enabling an ultimate narrow nanotube to terminate nanoribbons for α-puckered group-V elemental and compound monolayers (GeS/Se and SnS/Se). The reconstructed edge formations are confirmed by CALYPSO. The ZZ(Tube) edge forms easily, is highly stable, and is semiconducting. Remarkably, the ZZ(Tube) edge always exhibits a type-II band structure and robust spatial charge separation. For a compound monolayer monochalcogenide, mild (2 × 1) ZZ(S-R) occurs at the chalcogenide-terminated edge. TDDFT simulations indicate that charge separation occurs only at 672 fs, while the lifetime is over 5 ns, thus facilitating robust spatial charge accumulation. These remarkable features of ZZ(Tube) edge-terminated α-puckered nanoribbons are ideal for optoelectronic and photocatalytic applications.

Keywords: Edge reconstruction; charge separation; nanotube; zigzag edge; α-phase puckered monolayer.