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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 Cu2+ chemically bonds the surface of birnessite at the Mn vacancy site to form triple‐corner‐sharing inner‐sphere 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 ⋅O2− and 1O2, 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 1O2 for the radical pathway. [ABSTRACT FROM AUTHOR]

We analyze the generation of the vibrational coherent anti-Stokes Raman scattering (CARS) signal from the ground level X2Σg+ of N2+ and demonstrate the feasibility for gas-phase thermometry utilizing the vibrational CARS signals of N2+ in high-temperature flames. The vibrational CARS signal of N2+ is obtained using the filamentation-based and two-beam hybrid femtosecond/picosecond CARS system and is employed to extract the fitting temperatures in high-temperature flames. The accuracy and precision of the fitting temperatures from the 1000 consecutive single-shot vibrational CARS spectra of N2+ at a target temperature of 1706 K are 1.23% and 5.76%, respectively, which are similar to the fitting results of N2 in previous filamentation-based CARS thermometry and could also demonstrate that the measured temperature in the filamentation is indeed not affected by the ionization. We further introduce the CARS signal of N2+ in multiple species measurement to obtain more details about the CARS process during filamentation. This work would provide an optional target molecule for CARS thermometry and help researchers further understand the molecular dynamics of N2+ ions during the filamentation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We achieve two-beam, 1-kHz, and single-shot N2 vibrational coherent anti-Stokes Raman scattering (CARS) thermometry using hybrid femtosecond/picosecond CARS in high-temperature flames. Ultrabroadband pump/Stokes pulses are generated employing the filamentation of high-power femtosecond pulses and can excite the Raman shift up to ∼3000 cm−1. This configuration can avoid the need of a long hollow-core fiber and an additional supercontinuum compressor to obtain ultrabroadband pulses. The quasi-common-path second harmonic bandwidth compression system is utilized to generate narrow-band and sideband-free picosecond pulses, which are employed as the probe pulses in the CARS process. The accuracy and the precision of the fitting results from 1000 consecutive single-shot spectra at a target temperature of 1706 K are 0.66% and 4.47%, respectively. The results demonstrate that the simplified two-beam system has the potential for dynamic and accurate temperature measurement in practical applications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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, MoS 2 , is selected to construct a highly reactive sulfur ligand coordinated Fe species in this work. The Fe species doped in MoS 2 is presented as the Fe II centre and triggers the transformation of the 2H phase to the octahedral 1T phase MoS 2 . The role of the interaction between doped Fe and the MoS 2 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-MoS 2 . The quenching experiment was implemented to disclose the predominant role of oxoiron(IV) species in the Fe-MoS 2 /H 2 O 2 Fenton-like system. Furthermore, oxoiron(IV) species could transform into the ⋅O 2 - and 1 O 2 , which further expedites the Fenton-like reaction., (© 2022 Wiley-VCH GmbH.)