Developing carbon nitride with tailored defect structure for exceptional nonradical activation of peroxymonosulfate

Abstract

The nonradical activation of peroxymonosulfate (PMS) over nonmetallic catalyst remains a significant scientific challenge. Herein, we proposed a facile stepwise calcination approach to prepare fragmented carbon nitride (CN) with three coordinate nitrogen (N3C) vacancies (VCN). The defective structure comprising vacant and disintegrated nanosheet synergistically conferred VCN abundant unpaired electrons, providing an exceptional catalytic behavior to evolve nonradical pathway in PMS activation. This featured system allowed generating nonradical reactive species with 100 % selectivity, namely, a major singlet oxygenation and a spot of VCN/PMS complex-triggered oxidation, which enabled a high effectiveness in the degradation of Acid Orange 7 (almost 100 % removal efficiency within 20 min). Impressively, the VCN was also featured with excellent environment serviceability, long-term operational performance, and desirable non-photocatalytic efficiency in the PMS-mediated nonradical oxidation. Overall, this study offers a facile strategy for tailoring CN architecture to achieve PMS nonradical activation and contributes to an efficient strategy for wastewater remediation.