Cobalt-modified catalyst derived from cold-rolled sludge for phenol degradation via PMS-activated fenton-like reaction: Performance and mechanistic investigation.

The presence of pharmaceutical pollutants in water bodies represents a significant environmental and public health concern, largely due to their inherent persistence and potential to induce antibiotic resistance. Advanced oxidation processes (AOPs) that employ peroxymonosulfate (PMS) activation have emerged as an effective means of degrading these contaminants. Bismuth oxyiodides (BiOI), which are known for their visible-light photocatalytic properties, demonstrate considerable potential for removal of pharmaceutical pollutants. This study examines the synthesis and performance of BiOI-based composites with barium ferrite (BFO) nanoparticles for enhanced PMS activation under visible light. BiOI and Bi5O7I were synthesized via solvothermal and electrodeposition methods, respectively, and their morphologies and crystalline structures were observed to exhibit distinctive characteristics following annealing. The formation of the composite with BFO resulted in an improvement in the catalytic properties, which in turn enhanced the surface area and availability of active sites. The objective of the photocatalytic studies was to evaluate the degradation and mineralization of tetracycline (TC) under visible light, PMS, and combined conditions. The Bi5O7I(ED)-BFO catalyst was identified as the optimal candidate, achieving up to 99.8% TC degradation and 99.4% mineralization within 90 min at room temperature. The synergistic effect of BFO in BiOI-based composites significantly enhanced performance across all conditions, indicating their potential for efficient remediation of pharmaceutical pollutant. The material's performance was further evaluated in tap water, where the degradation efficiency decreased to 56.4% and mineralization to 38.2%. These results reflect the challenges posed by complex water matrices. However, doubling the PMS concentration to 5 mM led to improved outcomes, with 93.8% degradation and 81.4% mineralization achieved. These findings demonstrate the material's robust potential for treating pharmaceutical pollutants in real-world conditions, advancing sustainable water treatment technologies.

Efficient diclofenac removal by superoxide radical and singlet oxygen generated in surface Mn(II)/(III)/(IV) cycle dominated peroxymonosulfate activation system: Mechanism and product toxicity

Peroxymonosulfate conversion to singlet oxygen over π-electron delocalized carbon nitride for selective degradation of emerging contaminants

Enhanced activation of peroxymonosulfate by nitrogen-doped graphene/TiO2 under photo-assistance for organic pollutants degradation: Insight into N doping mechanism.

Fenton-like catalysis based on peroxymonosulfate (PMS) activation has shown great potential in the treatment of organic wastewater. Heterogeneous Fenton-like catalysts containing transition metal active sites are highly efficient for PMS activation. However, the reduction of oxidized metal active sites was usually not prompt due to the sluggish reaction kinetics, which caused the insufficient redox cycle of the metal active sites and further hampered the catalysis efficiency. Recent studies have shown that the synergy effect between photocatalysis and PMS activation may address the above obstacle and boost overall efficiency. However, a deeper understanding of this synergy effect is still missing, making it difficult to be rationally controlled; thus, a poor synergy effect is frequently reported. Herein, a Co/Fe bimetal-doped graphitic carbon nitride (g-C3N4) was designed representatively through systematical characterization and theoretical calculation, the synergy effect was revealed to be profoundly determined by the competitive role of a hole in the system and the adsorbed metastable PMS* on the catalyst surface, and furthermore, the synergy effect can be rationally manipulated; when the Co/Fe doping ratio is 2.5:2.5, the as-prepared g-C3N4 with a moderate valence band position can endow the catalyst with an optimized photo-Fenton-like synergistic effect and the highest catalytic degradation performance. This work sheds light on the rational design of highly efficient photo-Fenton-like catalysts.

High efficiency degradation of tetracycline by peroxymonosulfate activated with Fe/NC catalysts: Performance, intermediates, stability and mechanism

A metal-free Z-scheme PPy/MCN heterojunction for antibiotic removal via synergism of photocatalysis and peroxymonosulfate activation

The role of Fe-Nx single-atom catalytic sites in peroxymonosulfate activation: Formation of surface-activated complex and non-radical pathways

Improving peroxymonosulfate (PMS) activation efficiency to enhance simultaneous generation of radicals and non‐radicals is essential for removing new pollutants (NPs) in complex waters. However, achieving this with standard lattice‐structured heterogeneous catalysts remains challenging due to inefficient electron transfer. Here, CuCo2O4 properties are successfully tuned by controlling lattice distortion, enabling simultaneous PMS oxidation and reduction. Unlike the slow rate of electron transfer in heterogeneous metal catalysts with standard lattice structures, the highly active binary lattice distortion in CuCo2O4 alters the structure and electron distribution, exposes more Cu and Co sites, lowers the PMS adsorption barriers, and realizes the synergistic production of SO4•−/•OH), and 1O2. The k‐value for ciprofloxacin is as high as 17.83 min−1 M−1, 29.42 times higher than that with non‐binary lattice distortion. Additionally, the developed intermittent reactor consistently maintains a removal rate above 95% over five cycles in actual wastewater treatment scenarios. This work provides a new avenue for achieving the removal of new pollutants in complex water bodies.

Low-coordinated Co-N3 sites induce peroxymonosulfate activation for norfloxacin degradation via high-valent cobalt-oxo species and electron transfer

Efficient degradation of levofloxacin using a g-C3N4@glucose-derived carbon catalyst with adjustable N content via peroxymonosulfate activation

Ultrafast oxidation of refractory organics via PMS activation by Si-O doped biomimetic montmorillonite: Simultaneous enhanced radical/electron transfer pathways and efficient catalytic membrane system

Highly dispersed ZIF-67 derived cobalt nanoparticle supported on g-C3N4 for rapid degradation of sulfamethoxazole by Fenton-like oxidation: Enhanced adsorption and electron transfer.

Efficient degradation of organic contaminants in aqueous media using oxygen vacancy-rich MnO catalyst via peroxymonosulfate activation

A novel combination of bioelectrochemical system with peroxymonosulfate oxidation for enhanced azo dye degradation and MnFe2O4 catalyst regeneration