Coating of h-BN onto carbon nanotubes induces polarization at interfaces, and charges become localized at N and C atoms. Field emission of coated tubes is found to be highly stable, and current density fluctuates within 4%. Study further reveals that the electric field established between coatings and tubes facilitates charge transfer across interfaces and electrons are emitted through occupied and unoccupied bands of N and B atoms.
Keywords: Fowler−Nordheim equation; Mulliken charge; ab initio calculation; boron nitride; carbon nanotubes; field emission; interlayer polarization.