Boron nitride-graphene in-plane hexagonal heterostructure in oxygen environment

Insights into the progressive and subsequent  intercalation of oxygen, selective etching of graphene and oxidation of boron in a quasi-free standing Gr-h-BN monolayer during oxygen exposure. 

Applied Surface Science (2022)
The performances of devices based on 2D materials can be affected by their chemical stability, especially inambient environmental. Oxygen, in particular, can adsorb and alter the properties of these materials with significant impact to their applications. Oxygen is involved in most catalytic reactions and it can modify fundamentally the chemical and physical material properties due to oxidation, intercalation or etching.
At  the BACH beamline of IOM-CNR a lateral graphene (Gr)-hexagonal boron nitride (h-BN) heterostructure (h-BNG) on platinum was investigated in oxygen ambient. The measurements track the evolution of surface stoichiometry and chemical intermediates.

Among 2D materials, h-BNG merges the functionalities and the distinct properties of Gr and h-BN. Compared to a simple graphene (or h-BN) layers, this heterostructure includes additional possible catalytically active sites for the oxygen-reduction reaction through the bonds at the unique interface between h-BN and Gr domains. It is precisely around these sites that the our work was focused. 
Photoemission spectroscopy data unequivocally show the formation of B-O bonds at specific temperatures and oxygen exposures. Selective intercalation and selective etching is observed at specific conditions.

Based on the results a etching/regrowth method allowing a controlled synthesis of in-plane and vertically stacked h-BN/Gr heterostructures as well as tailoring the hexagonal boron nitride/graphene concentration using a single precursor is suggested, which can be beneficial for the development of versatile atomically thin layers for electronic devices.
We acknowledge support from MUR (Eurofel project, FOE progetti internazionali).

Boron nitride-graphene in-plane hexagonal heterostructure in oxygen environment
Applied Surface Science 
E. Magnano,  S. Nappini, I. Píš, T.O. Menteş, F. Genuzio, A. Locatelli and F. Bondino*
* Corresponding author bondino AT

Last Updated on Tuesday, 13 September 2022 14:36