Facilitating Redox Cycles of Copper Species by Pollutants in Peroxymonosulfate Activation

Abstract

The redox behavior of metal active sites determines the rate of heterogeneous catalysis in peroxymonosulfate activation. Previous reports focused on the construction of catalysts for accelerating interfacial electron transfer. In this work, a new strategy was proposed for facilitating valence cycles of Cu+/Cu2+ by using pollutants. The 2.5Cu/CeO2/PMS system was capable of achieving the efficient removal of pollutants, including tetracycline, oxytetracycline, and rhodamine B, in a wide pH working range. In the presence of tetracycline, a Cu–N bond was formed between the −NH2 group of tetracycline and the Cu site of the catalyst, showing that the coordination of Cu active sites changed to CuO4N1. The charge of CuO4N1 active sites rearranged, making it easier to obtain electrons and promote the PMS oxidation, thereby accelerating the reduction of Cu2+ to Cu+ and PMS activation. The PMS activation system showed excellent sustainability and selectivity for the removal of organic pollutants. This study provides a novel routine to promote peroxymonosulfate activation by utilizing pollutants to accelerate the redox behavior of metal species.

A nanoclay-confined single atom catalyst: tuning uncoordinated N species for efficient water treatment

“…A previous study revealed that pyrrolic N and single metal atom centers in SACs were the dominant adsorption sites for BPA and PMS, respectively. 15 In this work, p-MnNC@Mt-X (X = 700, 800, and 900) displays similar pyrrolic N content, which excludes the significant role of pyrrolic N in BPA adsorption. Hence, we only considered the influence of uncoordinated N species on the interaction between PMS and Mn single atom centers.…”

“…These are generally related to the coordination structure of NG-SACs. [12][13][14][15] Considering these features, we evaluated the role of uncoordinated N species in PMS activation, which is vital for the rational design of NG-SACs in environmental remediation. Developing a tunable and predictable approach for the synthesis of NG-SACs is critical to establishing the correlation between uncoordinated N species and catalytic properties of NG-SACs.…”

“…They can generate versatile reactive intermediates (sulfate radical , superoxide radicals , hydroxyl radicals (˙OH), and singlet oxygen ( 1 O 2 )) for pollutant removal. 12–15 These reactive processes can occur via a nonradical pathway to produce 1 O 2 or via a radical pathway to form ˙OH, , and . These are generally related to the coordination structure of NG-SACs.…”

“…These are generally related to the coordination structure of NG-SACs. 12–15 Considering these features, we evaluated the role of uncoordinated N species in PMS activation, which is vital for the rational design of NG-SACs in environmental remediation.…”

Sulfur vacancies on MoS2 enhanced the activation of peroxymonosulfate through the co-existence of radical and non-radical pathways to degrade organic pollutants in wastewater

“…Accordingly, it has to introduce external activation factors including heat, 6 alkaline conditions, 7 and homogeneous 8,9 and heterogeneous catalysts. [3][4][5][10][11][12][13][14][15] Among them, a heterogeneous catalyst for the activation of PMS is a good strategy for repeated use, realization of radical and non-radical routes, etc. The activation of PMS by heterogeneous catalysts containing defect sites has attracted much attention in the past few years.…”