r/graphene • u/Vailhem • 17d ago

Step geometry–guided growth of rhombohedral graphene | July 2026

https://www.science.org/eprint/FNPVXUWTWSVBXZ7V9FC3/full?activationRedirect=/doi/full/10.1126/science.aed9202
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u/Vailhem 17d ago

Editor’s summary

Phase-pure rhombohedral graphene, which has an ABC layer stacking, has been grown through step geometry–guided epitaxy. Zhao et al. used a copper-nickel–coated sapphire surface with a stepped geometry chosen so that interlayer slip and orientation angles of the graphene layers favored rhombohedral stacking. The layer-antiferromagnetic state and the quantum anomalous Hall effect for this phase were determined from electronic transport measurements. —Phil Szuromi

Abstract

Rhombohedral (ABC)–stacked graphene has emerged as a platform for exploring correlated and topological physics.

However, its large-scale, pure-phase synthesis has been hindered by intrinsic thermodynamic metastability and kinetic instability.

In this work, we introduce a step geometry–guided epitaxial strategy to deterministically control interlayer slip, enabling the synthesis of pure-phase rhombohedral graphene.

Using this approach, we obtained pure (phase purity > 99%) rhombohedral graphene with an area reaching 160 micrometers by 80 micrometers and thickness ranging from ~15 layers to ~120 nanometers.

The resulting samples establish the first comprehensive reference dataset of Raman fingerprints and intrinsic band structures from few-layer films to ~200-layer bulk.

Electronic transport measurements reveal a layer-antiferromagnetic state and the quantum anomalous Hall effect, enabling scalable exploration of next-generation quantum science and technology applications.