Covalent organic frameworks-derived hierarchically porous N-doped carbon for 2,4-dichlorophenol degradation by activated persulfate: The dual role of graphitic N

A series of hierarchically porous carbon catalysts with high N content and large surface area were prepared via self-templated carbonization of covalent organic frameworks (COFs). The catalyst was used to activate persulfate (PS) for degrading 2,4-dichlorophenol (2,4-DCP). Experimental results demonstrated that the prepared catalyst treated at 700 degrees C (PNC-700) showed both strong adsorption ability and enhanced PS activity for 2,4-DCP degradation. A variety of characterization techniques were used to investigate the properties of prepared catalysts. We found that the graphitic N functional groups acted as both activity sites and electron transfer access. The activity of the catalyst was also closely related to the hierarchical pore structure and good electrical conductivity. The influencing factors of PNC-700/PS system in 2,4-DCP degradation were discussed. In addition, PNC-700 displayed excellent recyclability. The activation process especially non-radical pathway was promoted by increasing graphitic N contents. The possible reaction mechanism and degradation pathways were also proposed.

Automated summary

Hierarchically porous carbon catalysts with high N content and large surface area were prepared via self-templated carbonization of COFs for PS activation in degrading 2,4-DCP. The catalyst showed strong adsorption ability and enhanced PS activity, with the graphitic N functional groups acting as both activity sites and electron transfer access. Increasing the graphitic N contents promoted the activation process, particularly the non-radical pathway, potentially improving degradation efficiency.