Oxidation of a two-dimensional hexagonal boron nitride monolayer: a first-principles study

Area of Science:

• Materials Science
• Surface Chemistry
• Computational Chemistry

Background:

• Two-dimensional (2D) hexagonal boron nitride (h-BN) is a graphene analogue with unique electronic properties.
• Graphene oxide research has spurred interest in the oxidation of related 2D materials.
• Understanding the oxidation of h-BN is key to controlling its properties for advanced applications.

Purpose of the Study:

• Investigate the chemical oxidation of 2D h-BN sheets.
• Determine the electronic properties of the resulting hexagonal boron nitride oxide (h-BNO).
• Identify favorable oxygen chemisorption sites and migration pathways on the h-BN surface.

Main Methods:

• Density Functional Theory (DFT) calculations were employed to model oxygen atom and molecule interactions with the h-BN surface.
• Analysis of oxygen atom migration barriers on top, bridge, and hollow sites.
• Simulation of oxygen molecule dissociation pathways on h-BN.

Main Results:

• Oxygen atoms preferentially migrate over nitrogen atoms, guided by neighboring boron atoms.
• Chemisorption of oxygen stretches and can break B-N bonds.
• Oxidation leads to the formation of oxygen domains or chains, potentially enabling h-BN sheet unzipping.

Conclusions:

• The study provides a detailed understanding of h-BN oxidation mechanisms.
• Findings offer insights into controlling h-BN structure and properties through oxidation.
• This research paves the way for tailored h-BN materials for diverse applications.