Probing moiré-assisted chemistry at the atomic scale

Twisted multilayer graphene hosts a long-range periodic moiré potential arising from alternating rhombohedral and Bernal stacking domains. Notably, these domains possess distinct electrochemical properties. Consequently, adsorbates adhere differently to these domains, enabling selective control of the local electrostatic environment. For example, metallic nanoparticles have been observed to adhere preferentially to rhombohedral regions over Bernal, providing sub-moiré unit cell doping selectivity. Here we present a scanning tunneling microscopy/spectroscopy study of twisted multilayer graphene with adsorbates. We examine how the charge transfer from adsorbates modifies the topography and the local density of states, and we map this response across the moiré lattice. These results expand the experimental toolkit for manipulating electronic phases in two-dimensional materials and further establish moiré-assisted surface chemistry as a route to site-selective functionalization.