Environmental Functional Materials最新文献

Atmospheric water harvesting is a promising strategy to address the water scarcity in islands. In this work, an activated carbon fiber (ACF) templated hybrid water adsorbent ACF-cobalt(II)-ethanolamine (ACF-Co-EA) was fabricated and used to build an ecological farm (Eco-farm) for potential application on tropical coral islands. ACF-Co-EA took the advantage of both the pore structure of ACF and the superabsorbent property of the Co-EA complex, thus, exhibiting superior water harvest capacity over ACF or Co-EA. The equilibrium water adsorption of ACF-Co-EA was 763 ​mg ​g⁻¹ ​at 25 ​°C and 70% RH (typical environment of tropical coral islands). Under 1 ​kW ​m⁻² simulated solar irradiation, the surface temperature of ACF-Co-EA increased rapidly to 50 ​°C within 12 ​min and stabilized at 54 ​°C in 30 ​min because of the superior light absorbance of ACF, which made more than 90% of captured water released. ACF-Co-EA-based Eco-farm could harvest 6.9 ​g ​g⁻¹·day⁻¹ of water to ensure plant growth in the tropical coral islands' environment without any additional energy or water supply. The study provided novel ideas to alleviate the problems of freshwater scarcity and food shortage in the tropical coral islands.

The heterogeneous activation of persulfate-based advanced oxidation processes (persulfate AOPs) has been defined as potential wastewater treatment methods due to their excellent chemical reactivity. However, the reaction mechanisms of these processes are extremely intricate because of the simultaneous participation of many substances from the solid, liquid, and even gas phases. The development of novel active catalysts is hindered due to divergent mechanisms and deficient research techniques. In this review, the up-to-date development of heterogeneous catalyst category, catalytic characteristics, and reaction mechanism are comprehensively discussed. Essentially, the detection of persulfate, the identification of reactive oxygen species, and the evolution and analysis of organic oxidation pathways are reviewed, highlighting the innovation integration experimental/theoretical protocol to reveal the reaction mechanism in a future study. Finally, the limitations and possible breakthrough directions of persulfate AOPs were discussed, including the further study of the internal reaction mechanism in persulfate AOPs, the requirement of reasonable evaluation of the treatment effect, and the feasibility of full-scale application.

Iron-based heterogeneous Fenton is a promising economic and eco-friendly technology in the degradation of organic pollutants, but the low conversion of ≡Fe³⁺ to ≡Fe²⁺ causes the low catalytic activity. Schwertmannite (Sch) formed via Fe(II) oxidation mediated by Acidithiobacillus ferrooxidans (A. ferrooxidans), resulting in the existence of low organic carbon (mainly from A. ferrooxidans cells) in Sch. Owing to magnetic inter-attraction between magnetosome-containing A. ferrooxidans and Fe₃O₄, A. ferrooxidans as organic carbon (OC) modified Fe₃O₄/Sch (namely Fe₃O₄/Sch/OC) was obtained by the introduction of Fe₃O₄ into synthetic process of Sch. Fe₃O₄/Sch/OC exhibited higher degradation efficiency (>95%) of antibiotics than Sch, Fe₃O₄ and Fe₃O₄/Sch, which was mainly ascribed to OC as electron donor and electron-transfer mediator for promoting ≡Fe²⁺ regeneration. Moreover, in situ H₂O₂ could be generated at a wide initial pH (3–9) via Fe₃O₄/Sch/OC-driven oxygen reduction reaction, and H₂O₂ was immediately activated to produce •OH for degrading organic pollutants (e.g., dyes, antibiotics). Considering the excellent arsenic (As) adsorption performance of Sch and the property of Fe₃O₄/Sch/OC to produce in situ H₂O₂, Fe₃O₄/Sch/OC-catalyzed in situ-generated H₂O₂ will be a promising strategy to synchronously remove antibiotics and As from livestock and poultry breeding wastewater.