Spintronic phase transition of graphene/BN/graphene van de Waals heterostructures

•The system exhibits metallic, half-metallic and semiconductor phases, under different Coulomb repulsion and local potentials.•A large local potential can destroy the half-metallicity.•The stacking sequence can be a new degree of freedom to tune the half-metallicity.•For large Coulomb repulsion, the evolution of bandgaps with interlayer AFM or FM magnetic orders exhibits different patterns.