Investigations of the tunable electronic properties of 2D borocarbonitrides, (BN)1-x(C)x, and of the epitaxial thin films of NiO generated by ALD

Abstract

Borocarbonitrides with the general formula, (BN)1-x(C)x (or BCN for simplicity) have emerged as a new class of 2D materials with fascinating properties.1,2 They can be considered as a network of BN and graphene domains, in addition to having BCN rings in the network.1,2 h-BN is a wide bandgap (~6 eV) insulator whereas graphene is a gapless conductor.3,4 Borocarbonitrides allow us to vary the bandgap between graphene and BN with the composition or with the carbon content. Since bandgap engineering and tuning of the electronic properties of semiconducting materials has many technological advantages, it appeared desirable to investigate BCN materials for the purpose.1,2,5,6 Many attempts have been made for bandgap engineering in graphene7 by induced strain,8,9 surface bonding, isoelectronic co-doping or chemical doping with nitrogen and other foreign atoms.10,11 These efforts have led only to a few meV changes in the bandgap.9 Bridging the optical gap between graphene to BN by chemical means is therefore more appealing. Even though there have been some efforts in this direction, there is a clear need for a systematic study where there is chemical control of the elemental composition.1