Stacking-Mode-Induced Reactivity Enhancement for Twisted Bilayer Graphene

Atomic registry has a strong impact on the electronic structure and properties of graphene due to its localized strain and localized charge distribution. However, direct experimental evidence of a correlation between its physical structure and chemical reactivity is still lacking. Here, we report that the electron transfer chemistry is significantly modified in twisted bilayer graphene (tBLG) by investigating the results of chemical functionalization with diazonium salts. The relative reaction rate for grafting diazonium salts on tBLG is much faster than that on AB-stacking graphene. Gerischer-Marcus electron transfer theory analysis, along with electronic structure calculations, indicates that the different reactivities mainly result from distinct variations in the density-of-states distribution in the gap region. Our results suggest a venue to separate and sort different stacking modes of bilayer graphene for various promising applications in nanoelectronics.