Non-radical activation of CaO2 nanoparticles by MgNCN/MgO composites for efficient remediation of organic and heavy metal-contaminated wastewater

Stable, cheap and environmentally friendly CaO 2 was widely used to remediate environmental pollution, especially in advanced oxidation process (AOP) systems. However, its non-radical activation was still a huge challenge. In this study, the non-radical activation of CaO 2 nanoparticles was realized by MgNCN/MgO composites for efficient remediation of organic and heavy metal-contaminated wastewater. The presented CaO 2 -based AOP system exhibited excellent degradation performance towards tetracycline (TC) and methylene blue (MB) over a broad pH range, accompanied with the weak influences of common coexisting anions and natural water sources. Singlet oxygen ( 1 O 2 ) was verified as the dominant active species for organics degradation, and the coordination between MgNCN and MgO in MgNCN/MgO composites played a crucial role in the non-radical activation of CaO 2 nanoparticles. More importantly, the AOP system could not only degraded effectively organic pollutants, but also remove simultaneously heavy metal ions in wastewater. 100 mg/L CaO 2 and MgNCN/MgO could successfully remediate the complex pollution consisting of 10 mg/L MB and 100 mg/L Cd 2+ . Furthermore, the degradation intermediates of MB and the solid residues after treating pollutants were analyzed in detail to reveal the degradation process and conversion products.