Fig. 4: Morphology and energetics of coated and uncoated MoS2 monolayers.

The area of monolayer MoS2 flake (1L-MoS2) is circled by white dotted lines. a Atomic force microscope (AFM) height image and b Kelvin probe force microscope (KPFM) image of a monolayer MoS2 flake. c Calculated electronic band structure of monolayer MoS2. d AFM image and e KPFM image of a CA·M doped MoS2 monolayer flake. f The band structure of monolayer MoS2/CA·M heterostructure. Contact potential difference (ΔVCPD) is the contact potential difference between the EF of the flake and that of the Au electrode (EF,MoS2 − EF,Au)/e. The energy level of conduction band minimum (ECBM) is marked with red solid lines, and the Fermi level (EF) is marked with the red dashed lines. Eg is the energy gap between conduction band minimum and valence band maximum.