Controllable modulation of the electronic properties of graphene and silicene by interface engineering and pressure

Using first-principles calculations, we show that the band gap and electron effective mass (EEM) of D-X/G/H-D, Si-X/S/H-Si and D-X/S/H-D can be modulated effectively by tuning the pressure (interlayer spacing) and stacking arrangement. The electron effective mass (EEM) is proportional to the band gap. The band gap of confined silicene is more sensitive to pressure than that of confined graphene. Moreover, a heterogeneous interface structure would be beneficial for effectively regulating the band gap and carrier effective masses of confined graphene and silicene. Using a confinement technique and pressure, the integrity of the honeycomb structure of graphene and silicene will be preserved so that the small effective masses and high mobility of graphene and silicene will be retained during compression. The tunable band gap and high carrier mobility of the sandwich structures are promising for building high-performance nanodevices.