Dandan Zhou

Hydroxyl radicals (•OH) were key radicals for the removal of organic contaminants from water. Peroxymonosulfate (PMS) activation had attracted broad interest as a route to •OH generation because of its asymmetric O–O bonds and ease of storage and transport. However, conventional Fenton-like activation of PMS typically produced •OH through a two-step pathway involving sulfate radicals (SO4•–), which incurred kinetic losses and limited •OH availability. Here, we reported a one-step •OH generation pathway from PMS enabled by synergistic polarization effects. This electronic regulation increased the O–O bond dipole moment from 0.45 to 3.86 D and produced a steady-state •OH concentration more than 2 orders of magnitude higher than those reported for representative state-of-the-art Fenton-like systems. Mechanistic analyses revealed that the amplified dipole promoted heterolytic O–O bond cleavage, thereby bypassing the SO4•– intermediate and enabling direct •OH generation. This system achieved efficient removal of diverse organic pollutants and increased rate constant of oxidant activation by 175–400% higher than the values reported for representative PMS/PDS-based Fenton-like systems. Life cycle assessment further revealed a lower environmental footprint, attributed to improved chemical utilization rates. This oxidant-centered strategy provided a promising route to utilize dipole polarization for efficient generation of •OH, with the potential to achieve scalable and low-carbon advanced oxidation water remediation.

Large ecotoxicity databases contain extensive evidence, yet heterogeneous reporting and sparse coverage across chemicals, species, end points, and conditions limit predictive use. From relational U.S. EPA ECOTOX, we linked 1,234,077 traceable records and constructed model-ready aquatic and soil data sets of 219,818 and 11,532 records. We developed a context-aware multitask model that preserves end point-specific responses while sharing information across molecular, biological, and experimental contexts. On held-out condition keys and parent-species-task combinations, four-seed ensembles achieved pooled R2 of 0.758/0.751 for aquatic toxicity and 0.628/0.537 for soil toxicity. Compared with same-input single-task models, multitask fitting reduced soil task-macro mean absolute error (MAE) by 0.136/0.156 across 16 task heads; aquatic point estimates also favored sharing, although uncertainty across all aquatic task heads was not estimable. Under canonical-parent holdout, frozen shared representations reduced task-macro MAE by 0.170–0.180 in aquatic and 0.093–0.125 in soil tree models versus molecular-only inputs, indicating reusable predictive information. Multidimensional training support stratified parent-holdout errors, meeting prespecified criteria fully for soil and partially for aquatic predictions; benefits weakened under stronger structural separation. These results show model-ready ECOTOX data can support context-aware toxicity prediction across a sparse experimental matrix, helping prioritize informative measurements and providing a predictive evidence base for environmental hazard assessment.

Photosynthetic hydrogen peroxide (H2O2) production from organic wastewater offers a sustainable alternative to the energy-intensive anthraquinone process, yet it is severely hindered by rapid quenching of reactive precursors by concentrated salts in hypersaline organic wastewater. Inspired by biological metabolic shunts, we propose a catalytic shunt strategy that spatially and functionally separates salts and organic contaminants through dynamic modulation of the catalyst electronic structure. Using an unsaturated Cr single-atom model catalyst, chloride ions (Cl–) are preferentially adsorbed onto active sites to enhance electron enrichment, while organic contaminants serve as proton donors. This system achieves a H2O2 production rate of 1.81 mM g–1 h–1, 172.3-fold higher than that of a representative photocatalytic system in pure water, and complete degradation of bisphenol A within 15 min, without external reagents. Mechanistic studies reveal that Cl– adsorption weakens *OOH binding to promote a two-electron oxygen reduction pathway, while contaminant protonation facilitates interfacial proton-coupled electron transfer. Life cycle assessment demonstrates substantially lower environmental burdens across 17 impact categories and a levelized H2O2 cost of \$70.6 per ton, well below the commercial price (\$140 per ton). This catalytic shunt paradigm transforms waste into a resource, enabling carbon-minimal, decentralized H2O2 production and sustainable remediation of hypersaline organic wastewater.

Humic acid (HA) can contribute to photochemical transformation of organic pollutants in natural waters via triplet-excited states (3HA*). However, in HA-containing water matrices for practical photocatalytic treatment (e.g., surface waters or wastewater effluents), HA is conventionally regarded as a persistent inhibitor; its rapid quenching of reactive species dominates the process, while the beneficial 3HA* pathway remains restricted by spin-forbidden singlet-to-triplet conversion. Herein, a heavy-atom-effect-driven molecular assembly with a bismuth catalyst was designed to overcome the spin-forbidden barrier limiting 3HA* formation. This strategy converted HA into an in situ promoter and increased antibiotic degradation by 4.24-fold. The catalyst formed a close-contact electron donor–acceptor (EDA) complex with HA, through which the bismuth heavy-atom effect enhanced spin–orbit coupling in attached HA, accelerated intersystem crossing, and raised 3HA* steady-state concentration by 12.1-fold. Explainable machine learning and multidimensional spectroscopy further revealed the molecular selectivity of this enhanced pathway, showing that higher-molecular-weight HA components rich in oxygenated groups and conjugated aromatic skeletons preferentially participated in the Bi3–P-enhanced photochemical process and were transformed into smaller products. The mechanism was validated in real water matrices, indicating that heavy-atom-enabled intersystem crossing can be leveraged to improve photocatalytic tolerance to organic backgrounds and guide photochemical design for water treatment.

Plastic pollution has become an increasingly severe global environmental issue, highlighting the urgent need for efficient and sustainable biodegradation strategies. In this study, an enriched gut microbial consortium, NE-01 derived from Tenebrio molitor, exhibited significant degradation activity toward polystyrene (PS), polyethylene (PE), and polyethylene terephthalate (PET). Metagenomic sequencing revealed that Pseudomonas and Proteobacteria were the dominant taxa, maintaining high community diversity and providing a microbial foundation for the degradation of plastics and other complex organic compounds. Functional annotation and metabolic pathway analysis indicated that xenobiotic biodegradation and metabolism occupied a large proportion of the metabolic network, suggesting the consortium’s potential for degrading exogenous pollutants. Several key genes associated with the degradation of aromatic and halogenated compounds, such as benzoate, toluene, styrene, and bisphenol A, were identified. Metabolic reconstruction further suggested possible degradation pathways for PS, PE, PET, and the plasticizer di(2-ethylhexyl) phthalate (DEHP). This study preliminarily demonstrated that the T. molitor gut-derived microbial consortium harbors multiple plastic-degrading genes and provides a theoretical basis for developing green, microbe-based strategies for plastic degradation.

Low-temperature conditions severely inhibited microbial metabolism and disrupted quorum sensing (QS) processes, leading to downregulation of nitrogen metabolism genes and a subsequent decline in denitrification efficiency. Given the high cost and instability of traditional N-acyl homoserine lactones (AHLs), novel metabolic activators are urgently needed. This study demonstrated that activated sludge microorganisms possess the capacity to synthesize various phytohormones, although the endogenous pool declined linearly with decreasing temperature. Notably, supplementation with 1 μM IBA was identified as an optimal strategy, enhancing 5°C denitrification activity by 37.2%. Mechanistically, IBA triggered the indole-QS cascade to induce an auxin biosynthesis, resolving cold-induced hormonal deficiency. This signaling flux reinforces antioxidant defenses, resulting in a 37.6% reduction in malondialdehyde (MDA) levels. Furthermore, IBA improves membrane fluidity by elevating monounsaturated fatty acids (MUFA) by 59.1% and carotenoids by 39.2%. These physiological adaptations stabilize the physical environment for electron transfer, leading to a 45.2% increase in electron transport system activity (ETSA). Consequently, this coordinated response enriches a psychrotolerant consortium of Acidovorax, Simplicispira and Azonexus, ensuring stable nitrogen removal at 5°C. This research provided novel insights into stabilizing cold-region wastewater treatment through phytohormone-based metabolic regulation.