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Recently, many reagents have been introduced to accelerate the formation of highly reactive intermediate Mn species from permanganate (KMnO 4 ), thereby improving the oxidation activity of KMnO 4 towards pollutants. However, most studies have mainly focused on sulfur-containing reducing agents (e.g., bisulfite and sodium sulfite), with little attention paid to nitrogen-containing reducing agents. This study found that hydroxylamine (HA) and hydroxylamine derivatives (HAs) can facilitate KMnO 4 in pollutant removal. Taking sulfamethoxazole (SMX) as a target contaminant, the effect of pH, SMX concentration, KMnO 4 and HA dosages, and the molar ratio of HA and KMnO 4 on the degradation of SMX in the KMnO 4 /HA process was systematically investigated. Quenching experiments and probe analysis revealed MnO 2 -catalyzed KMnO 4 oxidation, Mn(III) and reactive nitrogen species as the primary active species responsible for SMX oxidation in the KMnO 4 /HA system. Proposed transformation pathways of SMX in the KMnO 4 /HA system mainly involve hydroxylation and cleavage reactions. The KMnO 4 /HA system was more conducive to selective oxidation of SMX, 2,4-dichlorophenol, and several other pollutants, but reluctant to bisphenol S (BPS). Overall, this study proposed an effective system for eliminating pollutants, while providing mechanistic insight into HA-driven KMnO 4 activation for environmental remediation., (Copyright © 2024. Published by Elsevier B.V.)

Wearing face masks is the best way to stop the spread of respiratory infections. However, if masks are not sterilized, changing them too frequently can actually increase the risk of cross-contamination. Herein, the construction of an antipathogen photocatalytic mask with carbon vacancy-modified carbon nitride nanosheets (g-C 3 N 4 -V C Ns) coated on the non-woven fabrics of the out layer of the mask, offering effective and long-term protection against damaging pathogens when exposed to light is reported. The introduced carbon vacancies are found capable of creating energy-disordered sites and inducing energetic electric force to overcome the Coulomb interactions between electron-hole pairs, thus promoting the electron-hole separation to achieve a high generation of reactive oxygen species (ROS). Thanks to its high activity in generating ROS upon exposure to light, the as-prepared photocatalytic mask shows high pathogen sterilization performance. This, in turn, prolongs the mask's protective lifetime, decreases the need for regular replacement, and decreases medical waste production. The work demonstrated here opens new viewpoints in designing pathogens biocidal protective devices for health protection, offering significant promise in specific environment self-protection., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)