Joong-Eon Jung1,Sol Lee1,Han-gyu Kim1,Yangjin Lee1,Je Myoung Park2,Jeongsu Jang1,Joonho Kim1,Sangho Yoon3,Arnab Ghosh1,Jinsub Park1,Minseol Kim2,Woongki Na2,Jonghwan Kim3,Hyoung Joon Choi1,Hyeonsik Cheong2,Kwanpyo Kim1
Yonsei university1,Sogang University2,Pohang University of Science and Technology3
Joong-Eon Jung1,Sol Lee1,Han-gyu Kim1,Yangjin Lee1,Je Myoung Park2,Jeongsu Jang1,Joonho Kim1,Sangho Yoon3,Arnab Ghosh1,Jinsub Park1,Minseol Kim2,Woongki Na2,Jonghwan Kim3,Hyoung Joon Choi1,Hyeonsik Cheong2,Kwanpyo Kim1
Yonsei university1,Sogang University2,Pohang University of Science and Technology3
The family of group IV–VI monochalcogenides has an atomically puckered layered structure, and their atomic bond configuration suggests the possibility for the realization of various polymorphs. Here, we report the synthesis of the first hexagonal polymorph from the family of group IV–VI monochalcogenides, which is conventionally orthorhombic. Recently predicted four-atomic-thick hexagonal GeSe, so-called γ-GeSe, is synthesized and clearly identified by complementary structural characterizations, including elemental analysis, electron diffraction, high-resolution transmission electron microscopy imaging. The electrical and optical measurements indicate that synthesized γ-GeSe exhibits high electrical conductivity, which is comparable to those of other two-dimensional layered semimetallic crystals. The newly identified crystal symmetry of γ-GeSe warrants further studies on various physical properties of γ-GeSe.