Band gap opening of bilayer graphene by graphene oxide support doping

Abstract

The zero-band-gap features of monolayer and bilayer graphene (SLG and BG) limit their applications in logic circuits and photonic devices. Replacing adsorptions of foreign atoms or organic molecules, coupling of BG with derivatives of graphene provides a promising way to modify the electronic properties of BG. In this work, based on first-principles calculations, a sizeable bandgap is created in BG as it is supported on the highly stable graphene oxides (GOs). This result totally differs from the remaining semimetallic behavior of SLG supported on GOs revealed by previous works. The opened band gap can reach values as large as 245–261 meV, which depend on the structure of GOs substrates, including the oxidation species and their atomic arrangement. The effective p-type doping in BG is induced as GO substrates mainly contain the presence of single epoxides. More importantly, the high carrier mobility and large Fermi velocity in supported BG can be maintained due to the weak interaction with GOs. The band gap opening is attributed to the charge transfers between GOs and its neighboring graphene layer, which leads to a significant chemical potential difference between bilayer graphene. Thus, the present work provides a scientific basis for the development of high-performance graphene-based nanodevices.