Resolving few-layer antimonene/graphene heterostructures

Abstract

Abstract Two-dimensional (2D) antimony (Sb, “antimonene”) is of interest in electronics and batteries. Sb however exhibits a large allotropic structural diversity, which is also influenced by its support. Thus, Sb heterostructure formation is key in 2D Sb integration. Particularly, 2D Sb/graphene interfaces are important. We thus study here few-layered 2D Sb/graphene heterostructures with atomic resolution (scanning) transmission electron microscopy. We find two Sb morphologies to coexist: first, a 2D morphology of layered β-Sb with β-Sb(001)||graphene(001) texture. Second, one-dimensional Sb nanowires which can be matched to β-Sb[2-21]⊥graphene(001) and are closely related to cubic Sb(001)||graphene(001). Importantly, both Sb morphologies show rotational van-der-Waals epitaxy with graphene. Both are resilient against oxidation, although superficial Sb-oxide formation merits consideration, including epitaxial Sb2O3(111)/β-Sb(001) heterostructures. Exact Sb growth behavior depends on processing and substrate properties including, notably, the support underneath the graphene. Our work elucidates the rich phase and epitaxy landscape in 2D Sb and 2D Sb/graphene heterostructures.