It is generally found that enhancement in catalytic activity comes at the expense of selectivity or stability. In this study, an SO_x²⁻-modified Mn₂O₃ (SO-Mn₂O₃) solid catalyst was prepared using a simple oxalate precipitation method. This catalyst exhibited not only high catalytic activity but also high selectivity and good cycling stability. The degradation ratio of bisphenol A (BPA) under SO-Mn₂O₃ activated potassium peroxymonosulfate (PMS) achieved over 99% within 10 min, and the mineralization ratio increased to 83.2%. Particularly, the degradation rate for BPA under the SO-Mn₂O₃/PMS system was 15 times that of Mn₂O₃. Furthermore, the degradation ratio remained at 93.3% after five consecutive cycles. Multiple experimental characterizations confirmed that the introduction of SO_x²⁻ into Mn₂O₃ shifted the oxidative degradation pathway from a mixture of radical and non-radical routes to a predominantly non-radical pathway. This suppressed radical generation promoted the selective formation of high-valence metallic-oxo (Mn(V)=O) species and singlet oxygen (¹O₂), thereby significantly enhancing the catalytic activity. In addition, the SO-Mn₂O₃/PMS system exhibited broad applicability towards the degradation of other phenolic pollutants, strong anti-interference capability against complex water matrices, and suitability for efficient removal of organic contaminants in such environments. This research offers new perspectives for the design of selective catalysts for PMS activation.

It is generally found that enhancement in catalytic activity comes at the expense of selectivity or stability. In this study, a sulfur-modified Mn₂O₃ (S-Mn₂O₃) solid catalyst was prepared using a simple oxalate precipitation method. This catalyst exhibited not only high catalytic activity but also high selectivity and good cycling stability. The degradation ratio of bisphenol A (BPA) under S-Mn₂O₃ activated peroxymonosulfate (PMS) achieved over 99% within 10 minutes, and the mineralization ratio increased to 83.2%. Particularly, the degradation rate for BPA under of S-Mn₂O₃/PMS system was 15 times that of Mn₂O₃. Furthermore, the degradation ratio remained at 93.3% after five consecutive cycles. Multiple experimental characterizations confirmed that the introduction of S into Mn₂O₃ shifted the oxidative degradation pathway from a mixture of radical and non-radical routes to a predominantly non-radical pathway. This suppressed radical generation promoted the selective formation of high-valence metallic oxygen (HVMO) species and singlet oxygen (¹O₂), thereby significantly enhancing the catalytic activity. In addition, the S-Mn₂O₃/PMS system exhibited broad applicability towards the degradation of other phenolic pollutants, strong anti-interference capability against complex water matrices, and suitability for efficient removal of organic contaminants in such environments. This research offers new perspectives for the design of selective catalysts for PMS activation.

In this study, with the assist of thermal analysis, the stability of fraxinellone was systematically investigated. It is found that the pyrolysis reaction order of fraxinone in nitrogen is 1/4, while that in air is 2/3, which indicates that the stability of fraxinone in nitrogen is better than that in air. In addition, the action of fraxinellone in water is an endothermic reaction. Entropy change (ΔS_m) are all negative values, and Gibbs free energy (ΔG_m) are all positive values, indicating that the fraxinellone solution is relatively stable in pure water system. It is also worth noting that fraxinellone cannot remain stable in the atmosphere, and can be degraded in the natural environment.

Magnesium alloys are used or considered for lightweight structures and biodegradable implants, but high electrochemical activity, limited wear resistance, and localized corrosion still limit their service reliability. Plasma electrolytic oxidation (PEO), also called micro-arc oxidation (MAO), forms an adherent ceramic scaffold. Discharge channels, interconnected pores, thermal cracks, and a mechanically weak outer layer mean that the as-formed coating is rarely a complete protective system. This review examines advanced PEO/MAO-based composite coatings through a process–structure–function lens and develops an application-oriented design framework. The discussion covers PEO/MAO process-window control, electrolyte and particle engineering, sol–gel and polymer sealing, layered double hydroxide/inhibitor systems, self-healing reservoirs, superhydrophobic and slippery interfaces, Ca-P/hydroxyapatite and polymer biofunctionalization, and duplex coatings for wear, electrical, and thermal functions. Emphasis is placed on how these modules regulate defect connectivity, mass transport, interfacial stability, damage response, tribocorrosion, and biodegradation, as well as on the evidence needed to support each claimed function. The analysis indicates that coating performance is governed not by multilayer complexity alone, but by the compatibility among the ceramic scaffold, functional module, dominant failure mode, and service-specific validation protocol. Chloride-exposed structures require durable pore sealing and active inhibition; wear-critical components require coupled corrosion–wear assessment; and biodegradable implants require a degradation window that balances corrosion moderation, cytocompatibility, biofunctionality, and residual mechanical integrity. Remaining challenges include interfacial durability, finite inhibitor reservoirs, wetting-state instability, process reproducibility, scale-up, and life-cycle impacts. The proposed process maps and validation criteria are intended to support modular, testable, and application-specific PEO/MAO surface systems for magnesium alloys.