Facet-dependent Chemical Kinetics Governed Growth of Twisted Graphene Layers with Pre-designed Angles

Chaowu Xue; Mengzhao Sun; Zixuan Zhou; Zhuoran Yao; Li-Qun Shen; Xiao Kong; Honglong Zhao; Feng Ding; Marc Willinger; Zhongkai Liu; Zhu-Jun Wang

arXiv · 2604.15639

Facet-dependent Chemical Kinetics Governed Growth of Twisted Graphene Layers with Pre-designed Angles

Chaowu Xue·Mengzhao Sun·Zixuan Zhou·Zhuoran Yao·Li-Qun Shen·Xiao Kong·Honglong Zhao·Feng Ding·Marc Willinger·Zhongkai Liu·Zhu-Jun Wang

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Abstract

Twisted graphene layers (TGLs) provide a powerful platform for investigating multiple quantum phenomena, yet their scalable deployment is hindered by the lack of reliable synthesis with precise angle. Here, benefited from a deeper understanding of the interplay between grain index and graphene growth kinetics, we report a scalable strategy to grow TGLs with pre-designed twist angles on platinum (Pt) via chemical vapor deposition (CVD), Through a combination of complementary in situ methods, we identified the activity sequence of different Pt grains and attributed it to the area ratio of exposed (110) facets during graphene-induced surface reconstruction. Moreover, we revealed that CVD-grown graphene orientation is determined by the grain-orientation-dependent surface morphology. By leveraging the so-established correlations between grain index with both graphene growth priority and its orientation, we achieve controlled folding and tearing of graphene overlayer using a pair of adjacent grains with dramatically different catalytical activity and kink-free atomic steps. We reveal that overlayer-induced step bunching and terrace reconfiguration critically govern the domain morphology and folding direction. Building on this mechanistic insight, we demonstrate a substrate-engineering framework where specific platinum grains are rationally selected to yield TGLs with pre-designed twist angles, including magic angle with flat band dispersion. This work not only highlights fundamental kinetics of Pt catalyzed graphene CVD growth, but also offers a generalizable methodology for manipulating foldable two-dimensional materials via dynamic substrate reconstruction, exampled by programmable growth of high-quality TGLs on open surfaces.

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Chaowu Xue, Mengzhao Sun, Zixuan Zhou, Zhuoran Yao, Li-Qun Shen, Xiao Kong, Honglong Zhao, Feng Ding, Marc Willinger, Zhongkai Liu, Zhu-Jun Wang. 2026-04-17. Facet-dependent Chemical Kinetics Governed Growth of Twisted Graphene Layers with Pre-designed Angles. https://arxiv.org/abs/2604.15639

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