Electronic structures of hybrid graphane/boron nitride nanoribbons with hydrogen vacancies

Chi-Hsuan Lee,Chih-Kai Yang,Wei-Hua Tseng

doi:10.1063/1.4989771

Abstract

The electronic properties of hybrid graphane/boron-nitride nanoribbons with hydrogen vacancies are investigated using density functional calculations. Hydrogen vacancies in the shapes of lines and chains in the composite system are able to alter the electronic properties drastically. If segregated by a BN separator, H-vacancy chains may also be used for conduction of optically excited electrons on either edge of the BN, rendering it possible to create spatially distinctive conduction channels.

Highlights

Graphene and hexagonal boron nitride (h-BN) monolayers are two-dimensional (2-D) materials with the same honeycomb structures but hugely different electronic properties.[1]
The h-BN layer is an insulator with a wide energy gap.[3]
Having two H-vacancy chains segregated by a BN separator provides two spatially distinct conduction channels that can be generated by optical excitation

Summary

Introduction

Graphene and hexagonal boron nitride (h-BN) monolayers are two-dimensional (2-D) materials with the same honeycomb structures but hugely different electronic properties.[1] Graphene has the pz orbital perpendicular to the atomic plane and crossing linear energy bands near the Fermi level.[2] In contrast, the h-BN layer is an insulator with a wide energy gap.[3] Experimental and theoretical studies have shown that graphene can be turned into either n type or p type by replacing individual C atoms with N or B atoms respectively.[4,5,6] because of the similar lattice parameters between graphene and h-BN it is possible to construct a wide variety of hybrid 2-D structures out of the C and BN components, providing a very useful tool for manipulating electronic bands and tailoring physical properties for graphene-based structures. The process of the hydrogen adsorption is reversible.[9] H vacancies found in incomplete hydrogenation provide further opportunity for generating peculiar electronic, magnetic, and optical properties, and possible metal-insulator transition.[10]

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Conclusion