▎ 摘　　要

Interlayer carrier scattering hampers electrical conduction in two-dimensional layered nanostructures. Extenuated carrier scattering is observed in a double-layered graphene system with hexagonal boron nitride (h-BN) as an interposer. Raman spectrum shows signature peaks with enhanced sharpness as compared with that of bilayer graphene. The density functional theory simulation shows degenerate energy bands in the E-k dispersion. The decoupling of the two graphene monolayers is further confirmed by electrical conduction measurements. Improved carrier mobility is observed in the graphene/h-BN/graphene heterostructure as compared with exfoliated or randomly-stacked graphene bilayer, indicating preserved Fermi velocity. The demonstrated behavior in graphene/h-BN/graphene heterostructure suggests a pathway to preserve the excellent carrier transport of pristine graphene monolayer in a multichannel configuration, leading to implementation of highly conductive 2D heterostructure systems. (C) 2017 Elsevier Ltd. All rights reserved.