Quasi-freestanding monolayer heterostructure of graphene and hexagonal boron nitride on Ir(111) with a chiral boundary

Mengxi Liu; Yuanchang Li; Pengcheng Chen; Jingyu Sun; Donglin Ma; Teng Gao; Yabo Gao; Qiucheng Li; Zhihai Cheng; Xiaohui Qiu; Ying Fang; Yanfeng Zhang; Zhongfan Liu

arXiv · 1405.3357

Quasi-freestanding monolayer heterostructure of graphene and hexagonal boron nitride on Ir(111) with a chiral boundary

Mengxi Liu·Yuanchang Li·Pengcheng Chen·Jingyu Sun·Donglin Ma·Teng Gao·Yabo Gao·Qiucheng Li·Zhihai Cheng·Xiaohui Qiu·Ying Fang·Yanfeng Zhang·Zhongfan Liu

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Abstract

Monolayer lateral heterostructure of graphene and hexagonal boron nitride (h-BNC) has attracted a growing attention mainly due to its tunable band-gap character and unique physical properties at interface. Hereby, we reported the first-time synthesis of a nearly freestanding h-BNC hybrid on a weakly coupled substrate of Ir (111), where graphene and h-BN possessing different surface heights and corrugations formed a perfect monolayer hybrid. With the aid of scanning tunneling microscopy/spectroscopy (STM/STS), we demonstrated that h-BN can patch alongside the boundary of pre-deposited graphene domains and vice versa to form a seamless monolayer hybrid, with the realization of predominant zigzag type chiral boundaries at the interface. Density-functional theory calculations and STM/STS measurements aided us to reveal that this interface between graphene and h-BN were atomically sharp in aspects of the chemical bonding as well as the local electronic property from both theoretical and experimental points of view.

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Mengxi Liu, Yuanchang Li, Pengcheng Chen, Jingyu Sun, Donglin Ma, Teng Gao, Yabo Gao, Qiucheng Li, Zhihai Cheng, Xiaohui Qiu, Ying Fang, Yanfeng Zhang, Zhongfan Liu. 2014-05-14. Quasi-freestanding monolayer heterostructure of graphene and hexagonal boron nitride on Ir(111) with a chiral boundary. https://arxiv.org/abs/1405.3357

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