Cooperative Pollutant Adsorption and Persulfate-Driven Oxidation on Hierarchically Ordered Porous Carbon

This study presents a 3D hierarchically ordered porous carbon material (HOPC) that simultaneously achieves efficient adsorption of a range of water pollutants as well as catalytic oxidation of adsorbed pollutants. High adsorption capacity and rapid adsorption kinetics are attributed to the hydrophobic nature of the carbon substrate, the large surface area due to high porosity, and the relatively uniform size of pores that comprise the structure. The oxidative degradation is achieved by efficient mediation of electron transfer from pollutants to persulfate through the sp2-hybridized carbon and nitrogen network. As the persulfate activation and pollutant oxidation do not involve reactive radicals, oxidative degradation of the adsorbent is prevented, which has been a primary concern when adsorption and oxidation are combined either to regenerate adsorbate or to enhance oxidation performance. Batch tests showed that near complete removal of various recalcitrant micropollutants can be achieved within a short time (less than 1 min) even when treating a complex water matrix, as pollutants are concentrated on the surface of HOPC, where their oxidation is catalyzed.