Quasi-free-standing monolayer hexagonal boron nitride on Ni

TL;DR

This study investigates the electronic structure of monolayer hexagonal boron nitride on Ni, revealing it remains quasi-free-standing without hybridization, contrasting previous findings due to surface orientation differences.

Contribution

It demonstrates that the absence of Ni(111) surface orientation prevents hybridization, showing the importance of surface structure in h-BN/Ni interactions.

Findings

No hybridization between h-BN and Ni observed

Quasi-free-standing state of monolayer h-BN confirmed

Surface orientation critically affects orbital hybridization

Abstract

The electronic structure of monolayer hexagonal boron nitride grown on Ni by the diffusion and precipitation method was studied by x-ray absorption spectroscopy, emission spectroscopy, x-ray photoelectron spectroscopy and micro-ultraviolet photoemission spectroscopy. No indication of hybridization between h-BN pi and Ni 3d orbitals was observed. That is, the monolayer h-BN was found to be in the quasi-free-standing state. These results are in striking contrast to those of previous studies in which h-BN was strongly bound to the Ni surface by the orbital hybridization. The absence of hybridization is attributed to absence of a Ni(111) surface in this study. The lattice-matched Ni(111) surface is considered to be essential to orbital hybridization between h-BN and Ni.