Ozone adsorption on graphene: ab initio study and experimental validation

TL;DR

This study combines ab initio calculations and experiments to analyze ozone's reversible adsorption on graphene, revealing potential for chemical functionalization of graphene surfaces.

Contribution

It provides the first combined theoretical and experimental analysis of ozone adsorption and chemisorption mechanisms on graphene.

Findings

Ozone adsorbs on graphene with a binding energy of 0.25 eV.

Chemisorption involves formation of epoxide groups and oxygen molecules.

Experimental validation confirms the presence of functional groups on graphene.

Abstract

We have investigated ozone adsorption on graphene using the ab initio density functional theory method. Ozone molecules adsorb on graphene basal plane with binding energy of 0.25 eV, and the physisorbed molecule can chemically react with graphene to form an epoxide group and an oxygen molecule. The activation energy barrier from physisorption to chemisorption is 0.72 eV, and the chemisorbed state has the binding energy of 0.33 eV. These binding energies and energy barrier indicate that the ozone adsorption on graphene is gentle and reversible. Atomic layer deposition experiment on ozone treated graphite has confirmed the presence of uniform hydrophilic groups on graphene basal plane. This finding can be applied to diverse chemical functionalization of graphene basal planes.