Pristine graphene is gapless semiconductor and lacks the necessary band gap to turn off the electric current completely,which would disqualify graphene to serve as a transistor or other microelectronics devices.A considerable band gap can be opened for graphene by hydrogenation or fluorination,however,the band gaps of hydrogenated and fluorinated graphene are usually too large for practical applications.By means of first-principles computations,we systematically investigated the effect of some weak interactions,including hydrogen bonding,van der Waals(vdW)force,and electrostatic interaction on the band structures of graphene and its derivatives.By constructing various two dimensional(2D)heterogeneous and homogeneous bilayer structures,we sucessfully figured out some effective approaches to open a band gap for graphene and reduce the band gap for graphene derivatives,which would pave the way for their applications in electronics devices.