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arXiv · 2309.05319

Janus-graphene: a two-dimensional half-auxetic carbon allotropes with non-chemical Janus configuration

Linfeng Yu·Jianhua Xu·Chen Shen·Hongbin Zhang·Xiong Zheng·Huiming Wang·Zhenzhen Qin·Guangzhao Qin
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Abstract

The asymmetric properties of Janus two-dimensional materials commonly depend on chemical effects, such as different atoms, elements, material types, etc. Herein, based on carbon gene recombination strategy, we identify an intrinsic non-chemical Janus configuration in a novel purely sp$^2$ hybridized carbon monolayer, named as Janus-graphene. With the carbon gene of tetragonal, hexagonal, and octagonal rings, the spontaneous unilateral growth of carbon atoms drives the non-chemical Janus configuration in Janus-graphene, which is totally different from the chemical effect in common Janus materials such as MoSSe. A structure-independent half-auxetic behavior is mapped in Janus-graphene that the structure maintains expansion whether stretched or compressed, which lies in the key role of $p_z$ orbital. The unprecedented half-auxeticity in Janus-graphene extends intrinsic auxeticity into pure sp$^2$ hybrid carbon configurations. With the unique half-auxeticity emerged in the non-chemical Janus configuration, Janus-graphene enriches the functional carbon family as a promising candidate for micro/nanoelectronic device applications.

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Linfeng Yu, Jianhua Xu, Chen Shen, Hongbin Zhang, Xiong Zheng, Huiming Wang, Zhenzhen Qin, Guangzhao Qin. 2023-09-11. Janus-graphene: a two-dimensional half-auxetic carbon allotropes with non-chemical Janus configuration. https://arxiv.org/abs/2309.05319

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