ZIF-8 derived defect-rich nitrogen-doped carbon with enhanced catalytic activity for efficient non-radical activation of peroxydisulfate.

The non-radical oxidation processes of persulfate activation by carbon materials have shown great potential for industrial and saline wastewater treatment. Recently, metal-organic frameworks (MOFs) as an emerging precursor have been widely used for fabricating functional carbon materials. Herein, we reported ZIF-8 derived defect-rich nitrogen-doped carbon (ZCNs) via NaCl-assisted pyrolysis for efficient non-radical activation of peroxydisulfate to degrade rhodamine B (RB). All samples exhibited excellent catalytic activity, and ZCN-900 (pyrolyzed at 900 °C) was found to be the most active, able to degrade 96 % of RB quickly within 10 min. Quenching tests and electron paramagnetic resonance (EPR) analyses suggested that the singlet oxygen (O) dominated the degradation process by a non-radical pathway. Furthermore, the effect of anions and water quality on RB oxidation were investigated, and ZCN-900/PDS system showed great resistance to the anions and natural organic matters (NOM). This work may provide a significant addition to MOF-based functional materials for environmental remediation based on the results above.