Resolving Few-Layer Antimonene/Graphene Heterostructures

Tushar Gupta; Kenan Elibol; Stefan Hummel; Michael Stöger-Pollach; Clemens Mangler; Gerlinde Habler; Jannik C. Meyer; Dominik Eder; Bernhard C. Bayer

arXiv · 2009.03097

Resolving Few-Layer Antimonene/Graphene Heterostructures

Tushar Gupta·Kenan Elibol·Stefan Hummel·Michael Stöger-Pollach·Clemens Mangler·Gerlinde Habler·Jannik C. Meyer·Dominik Eder·Bernhard C. Bayer

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Abstract

Two-dimensional (2D) antimony (Sb, antimonene) recently attracted interest due to its peculiar electronic properties and its suitability as anode material in next generation batteries. Sb however exhibits a large polymorphic/allotropic structural diversity, which is also influenced by the Sb's support. Thus understanding Sb heterostructure formation is key in 2D Sb integration. Particularly 2D Sb/graphene interfaces are of prime importance as contacts in electronics and electrodes in batteries. We thus study here few-layered 2D Sb/graphene heterostructures by atomic-resolution (scanning) transmission electron microscopy. We find the co-existence of two Sb morphologies: First is a 2D growth morphology of layered beta-Sb with beta-Sb(001)||graphene(001) texture. Second are one-dimensional (1D) Sb nanowires which can be matched to beta-Sb with beta-Sb[2-21] perpendicular to graphene(001) texture and are structurally also closely related to thermodynamically non-preferred cubic Sb(001)||graphene(001). Importantly, both Sb morphologies show rotational van-der-Waals epitaxy with the graphene support. Both Sb morphologies are well resilient against environmental bulk oxidation, although superficial Sb-oxide layer formation merits consideration, including formation of novel epitaxial Sb2O3(111)/beta-Sb(001) heterostructures. Exact Sb growth behavior is sensitive on employed processing and substrate properties including, notably, the nature of the support underneath the direct graphene support. This introduces the substrate underneath a direct 2D support as a key parameter in 2D Sb heterostructure formation. Our work provides insights into the rich phase and epitaxy landscape in 2D Sb and 2D Sb/graphene heterostructures.

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Tushar Gupta, Kenan Elibol, Stefan Hummel, Michael Stöger-Pollach, Clemens Mangler, Gerlinde Habler, Jannik C. Meyer, Dominik Eder, Bernhard C. Bayer. 2020-09-07. Resolving Few-Layer Antimonene/Graphene Heterostructures. https://arxiv.org/abs/2009.03097

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