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arXiv · 2106.11599

Intrinsically Honeycomb-patterned Hydrogenated Graphene with Spin Polarized Edge-states

Yang Song·Kai Qian·Lei Tao·Zhenyu Wang·Hui Guo·Hui Chen·Shuai Zhang·Yu-Yang Zhang·Xiao Lin·Sokrates T. Pantelides·Shixuan Du·Hong-Jun Gao
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Abstract

Since the advent of graphene ushered the era of two-dimensional materials, many forms of hydrogenated graphene have been reported, exhibiting diverse properties ranging from a tunable band gap to ferromagnetic ordering. Patterned hydrogenated graphene with micron-scale patterns has been fabricated by lithographic means. Here we report successful millimeter-scale synthesis of an intrinsically honeycomb patterned form of hydrogenated graphene on Ru(0001) by epitaxial growth followed by hydrogenation. Combining scanning tunneling microscopy observations with density-functional-theory (DFT) calculations, we reveal that an atomic-hydrogen layer intercalates between graphene and Ru(0001). The result is a hydrogen honeycomb structure that serves as a template for the final hydrogenation, which converts the graphene into graphane only over the template, yielding honeycomb-patterned hydrogenated graphene (HPHG). In effect, HPHG is a form of patterned graphane. DFT calculations find that the unhydrogenated graphene regions embedded in the patterned graphane exhibit spin-polarized edge states. This type of growth mechanism provides new pathways for the fabrication of intrinsically patterned graphene-based materials.

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Yang Song, Kai Qian, Lei Tao, Zhenyu Wang, Hui Guo, Hui Chen, Shuai Zhang, Yu-Yang Zhang, Xiao Lin, Sokrates T. Pantelides, Shixuan Du, Hong-Jun Gao. 2021-06-22. Intrinsically Honeycomb-patterned Hydrogenated Graphene with Spin Polarized Edge-states. https://arxiv.org/abs/2106.11599

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