Graphene heterostructures

It is well known that graphene has ultrahigh carrier mobility. However, the zero bandgap of graphene will lead to a large leaking current in graphene-based transistors and, therefore, limits its application in high-performance semiconducting electronics. Creation of graphene heterostructures will not only result in graphene-based artificial architectures that open the bandgap of graphene, but also pave a promising way to the landscape of full-integrated and multifunctional graphene electronics. By integrating graphene with its analogs such as hexago nal boron nitride (h-BN)¹ and dichogenides (e.g., MoS₂),^2-5 one can tailor the graphene transport in terms of mobility, ON/OFF ratio,⁶ radio frequency,⁷ and etc. Generally, one can divide the graphene heterostructures into two classes: Pla nar layers^2,7 and vertical stack, which can be approached by various ways. With controlled number of layers, ordering of layers, and manipulation of the positions of the layers, such heterostructures will lead to vast applications such as in high performance transistors, radio frequency devices, and in THz rectifiers. Besides the two-dimensional graphene heterostruc tures, the three-dimensional heterostructure of graphene and carbon nanotubes (CNTs) can be realized via bonding CNTs with graphene for energy applications.