▎ 摘　　要

In real device application, the sealing of graphene as that in the silicon microelectronic industry is required to ensure a stable local environment. In this work, through first-principles calculations, we demonstrate that single-atomic-thick graphene and graphene nanoribbons (GNRs) sealed between diamond layers maintain their intrinsic electronic properties. Furthermore, the study shows that the doping type and level and the conductivity of sealed graphene and GNRs can be tuned through the external pressure or the selection of the sealing material. This opens a door of using sealed graphene/GNR to replace the recently used freestanding or supported ones for robust electronic/spintronic device synthesis.