• DOI:10.1038/s41557-021-00865-1
• Corpus ID: 237091746

Tunable electrochemistry with moir\'e flat bands and topological defects at twisted bilayer graphene

@inproceedings{Yu2021TunableEW,
  title={Tunable electrochemistry with moir\'e flat bands and topological defects at twisted bilayer graphene},
  author={Yun Yu and Kaidi Zhang and Holden L Parks and Md. Babar and Stephen Carr and Isabel Craig and Madeline Van Winkle and Artur Lyssenko and Takashi Taniguchi and Kenji Watanabe and Venkatasubramanian Viswanathan and D. Kwabena Bediako},
  year={2021}
}

• Yun Yu, Kaidi Zhang, +9 authors D. K. Bediako
• Published 15 August 2021
• Physics, Materials Science

Tailoring electron transfer dynamics across solid–liquid interfaces is fundamental to the interconversion of electrical and chemical energy. Stacking atomically thin layers with a very small azimuthal misorientation to produce moiré superlattices enables the controlled engineering of electronic band structures and the formation of extremely flat electronic bands. Here, we report a strong twist angle dependence of heterogeneous charge transfer kinetics at twisted bilayer graphene electrodes with the greatest enhancement observed near the ‘magic angle’ (~1.1o). This effect is driven by the angle-dependent tuning of moiré-derived flat bands that modulate electron transfer processes with the solution-phase redox couple. Combined experimental and computational analysis reveals that the variation in electrochemical activity with moiré angle is controlled by atomic reconstruction of the moiré superlattice at twist angles <2o, and topological defect AA stacking regions produce a large anomalous local electrochemical enhancement that cannot be accounted for by the elevated local density of states alone. Our results introduce moiré flat band materials as a distinctively tunable paradigm for mediating electrochemical