The nitrogen-rich multi-layer porous Cu-C-N composite removes BPA via synergistic adsorption and peroxymonosulfate activation

To develop an efficient bifunctional material for bisphenol A (BPA) removal, a nitrogen-rich hierarchical porous Cu x @N-CM composite was synthesized by pyrolyzing Cu@ZIF-8 encapsulated with dicyandiamide (DCD). DCD introduced more pyridinic N, graphitic N, and Cu-N x active sites, and enhanced the material’s surface area and pore size. This unique structure endows the material with both superior adsorption capacity and peroxymonosulfate (PMS) activation ability, enabling efficient BPA removal from water. Specifically, after adsorption enrichment, 0.1 g L −1 of Cu x @N-CM can remove 75 % of BPA (20 mg L −1 ). Subsequent addition of 0.1 mmol L −1 PMS achieves complete BPA removal within 15 min. Furthermore, this material and process effectively minimize PMS consumption, exhibit a broad pH application range, and good cycling stability. Mechanistic studies show that adsorption occurs through pore filling, hydrophobic interactions, π-π electron donor-acceptor (EDA) interactions, and complexation. PMS activation is driven by radical and non-radical synergies. In addition, the adsorption active sites and PMS activation sites do not overlap, and the adsorption process prolongs the residence time of pollutants on the catalyst surface, thereby promoting the degradation process. This study provides valuable insights into designing catalysts for removing high-concentration, refractory organic pollutants from water.