No abstract

No abstract

The peroxymonosulfate (PMS) activation mechanism is closely related to the structure/configuration of the "active site" of the Fenton-like catalysts. In this paper, it is shown that Cu 2 + chemically bonds the surface of birnessite at the Mn vacancy site to form triple-corner-sharing innersphere surface complexes (Cu-Bir), which regulates the PMS activation mechanism. Birnessite/PMS Fenton-like system degrades phenol via a non-radical mechanism, which involves high valent Mn(V) = O generated from the surface reaction of Mn(III) with adsorbed PMS. While Cu-Bir initiates an additional radical mechanism that involves reactive oxygen species of •O 2 À and 1 O 2 , and the k value of 5Cu-Bir is 1.9 times higher than that of Bir. The Fenton-like reaction mechanism of the Cu-Bir/PMS system is thus proposed as a radical and non-radical cooccurrence mechanism, which involves a synergistic effect that the radical pathway accelerates the regeneration of Mn(III) for the non-radical pathway, and the non-radical pathway assists to produce 1 O 2 for the radical pathway.

Oxoiron(IV) species are a critical intermediate in the Fe‐based Fenton‐like process at circumneutral pH, and its oxidative reactivity is closely related to the ligands. An optional inorganic host material, MoS2, is selected to construct a highly reactive sulfur ligand coordinated Fe species in this work. The Fe species doped in MoS2 is presented as the FeII centre and triggers the transformation of the 2H phase to the octahedral 1T phase MoS2. The role of the interaction between doped Fe and the MoS2 host lattice on the formation of oxoiron(IV) is studied. A significant Fenton‐like reactivity and a remarkable accumulation of oxoiron(IV) species were observed for Fe‐MoS2. The quenching experiment was implemented to disclose the predominant role of oxoiron(IV) species in the Fe‐MoS2/H2O2 Fenton‐like system. Furthermore, oxoiron(IV) species could transform into the ⋅O2− and 1O2, which further expedites the Fenton‐like reaction.

No abstract