Fig. 1

Schematic representation of the material and of the experimental setup. a Li⁺, Na⁺, and K⁺ intercalation into MoS₂ through top and edge channels. b An electrochemical cell used to perform intercalation of Li⁺, Na⁺, and K⁺ into MoS₂ with sealed and open edge. c-d AFM and optical microscopy images of typical MoS₂ flakes designed for sealed edge measurement and open edge measurement, respectively. The thicknesses are typically < 10 nm, measured across three edges indicated by the dash lines. Scale bars in c and d, 5 µm