Figure 6: DFT-simulated structures and their electronic properties.

(a) Typical electrostatic potential plot and tunnelling barrier height ΔV as a function of separation distance between two graphene layers (d). (b) d-dependent band gap. (c) Left, optimized G/PBASE/G structure, where and
; right, its corresponding electrostatic potential. (d) Band structure of G/PBASE/G at κ-point. (e) Left, optimized G/1-pyrenebutanol/G device. The
and
are about 3.6 and 2.5 Å; right, its corresponding electrostatic potential. (f) Band structure of G/1-pyrenebutanol/G at κ-point.