Abstract
LaB6 has a low work function and is used as a thermionic cathode, but further work function reduction and maintenance of the low work function state are needed. In this study, graphene and hexagonal boron nitride (hBN) were coated on the surface of LaB6 by a wet transfer method, and the work function change was investigated by photoelectron emission microscopy and synchrotron radiation XPS. The DFT calculations also showed a decrease in the work function. On the other hand, the work function increased for graphene. This is due to the dipole effect at the interface, where the outward dipole forms in hBN and the work function decreases, while in graphene the work function increases due to the inward dipole.
https://ror.org/05jk51a88 
