Catalytic Ozonation Using Edge-Hydroxylated Graphite-Based Materials

Abstract

This work reports the catalytic ozonation activity of high surface area graphite materials selectively functionalized at the edges with hydroxyl groups. The graphite-based catalyst shows higher activity than the parent graphite, commercial activated carbon, commercial multiwall carbon nanotubes, commercial diamond nanoparticles, graphene oxide, or reduced graphene oxide. Importantly, the catalytic activity of the graphite-based material is also higher than those of benchmark ozonation catalysts such as Co3O4 or Fe2O3. The graphite catalyst was reused up to 10 times with only a minor decrease in the catalytic activity. Catalytic activation of O3 leads to the generation of hydroperoxide radicals and 1O2. These results have been interpreted as derived from the combination of a suitable work function and the presence of phenolic/semiquinone-like redox pairs, as well as high dispersibility in water due to the presence of −OH groups. This work highlights the possibility of engineering active and stable carbocatalysts for reactions typically promoted by transition metals.