Defect-rich carbon nanofiber membranes as metal-free catalysts for flow-through peroxymonosulfate activation: toward efficient antibiotic removal and water remediation

Multifunctional ZnO nanorod-reduced graphene oxide hybrids nanocomposites for effective water remediation: Effective sunlight driven degradation of organic dyes and rapid heavy metal adsorption

Bio-inspired cracked metal-phenolic networks with durable confinement capillarity and photocatalysis for highly efficient evaporation and water remediation.

Copper-substituted polyoxometalate-soldered interpenetrating polymeric networks membranes for water remediation

The development and investigation of materials that leverage unique interfacial effects on electronic structure and redox chemistry are likely to play an outstanding role in advanced technologies for wastewater treatment. Here, the use of surface functionalization of metal oxides with a RuII poly(pyridyl) complex was reported as a way to create hybrid assemblies with optimized electrochemical performance for water remediation, superior to those that could be achieved with the molecular catalyst or metal-oxide electrodes used individually. Mechanistic analysis demonstrated that the molecularly functionalized electrodes could suppress the formation of hydroxyl radicals (i. e., the dominant remediation pathway for bare metal-oxide electrodes), allowing the water remediation to proceed through the highly oxidizing Ru3+ ions in the surface-bound complexes. Furthermore, the underlying metal-oxide substrates played a crucial role in altering the electronic structure and electrochemical properties of the surface-bound catalyst, such that the competing side reaction (i. e., water splitting) was largely inhibited.

As global populations continue to increase, the pressure on water supplies will inevitably intensify. Consequently the international need for more efficient and cost effective water remediation technologies will also rise. The introduction of nano-technology into the industry may represent a significant advancement and zero-valent iron nano-particles (INPs) have been thoroughly studied for potential remediation applications. However, the application of water dispersed INP suspensions is limited and somewhat contentious on the grounds of safety, whilst INP reaction mechanisms, transport properties and ecotoxicity are areas still under investigation. Theoretically, the development of nano-composites containing INPs to overcome these issues provides the logical next step for developing nano-materials that are better suited to wide application across the water industry. This review provides an overview of the range of static, bulk nano-composites containing INPs being developed, whilst highlighting the limitations of individual solutions, overall classes of technology, and lack of comparative testing for nano-composites. The review discusses what further developments are needed to optimize nano-composite water remediation systems to subsequently achieve commercial maturity.

Precursor-oriented design of nano-alumina for efficient removal of antibiotics

Emerging single-atom catalysts (SACs) are promising in water remediation through Fenton-like reactions. Despite the notable enhancement of catalytic activity through increasing the density of single-atom active sites, the performance improvement is not solely attributed to the increase in the number of active sites. The variation of catalytic behaviors stemming from the increased atomic density is particularly elusive and deserves an in-depth study. Herein, single-atom Fe catalysts (FeSA-CN) with different distances (dsite) between the adjacent single-atom Fe sites are constructed by controlling Fe loading. With the decrease in dsite value, remarkably enhanced catalytic activity of FeSA-CN is realized via the electron transfer regime with peroxymonosulfate (PMS) activation. The decrease in dsite value promotes electronic communication and further alters the electronic structure in favor of PMS activation. Moreover, the two adjacent single-atom Fe sites collectively adsorb PMS and achieve single-site desorption of the PMS decomposition products, maintaining continuous PMS activation and contaminant removal. Moreover, the FeSA-CN/PMS system exhibits excellent anti-interference performance for various aquatic systems and good durability in continuous-flow experiments, indicating its great potential for water treatment applications. This study provides an in-depth understanding of the distance effect of single-atom active sites on water remediation by designing densely populated SACs.

The removal of antibiotics by adsorption was considered to be a cheap and efficient treatment method. Herein, magnetic NiFe2O4/biochar (NFO/BC) composites were prepared by hydrothermal growth of nickel ferrite nanoparticles on sawdust derived biochar. It was found that NFO/BC composites had developed pore structure, rich oxygen-containing functional groups, and strong magnetism. The maximum adsorption capacity of the prepared magnetic composite for tetracycline (TC) was 420.41 mg g−1. The results of adsorption thermodynamics and adsorption kinetics showed that the adsorption process is a spontaneous process, which conforms to Langmuir model and pseudo second-order kinetic model. The influence experiment of pH and ionic strength confirmed that electrostatic interaction and hydrogen bonding are the key factors affecting the adsorption process. Additionally, pore filling and π-π interaction also existed in the adsorption process of tetracycline. This recyclable magnetic composite provides a feasible research idea for the efficient removal of antibiotics from water.Graphical

Fe–Si–B amorphous alloy ribbons (Fe–Si–BAR) are widely investigated recently due to its high efficiency in remediation of wastewater containing azo dyes and other organic pollutants. In this paper, the effects of Fe–Si–BAR on the remediation of water containing high levels of Cu2+ ions were discussed. Results show that the reaction mechanism of Fe–Si–BAR with Cu2+ ions solution is the same as iron powders (FeCP). But the reaction efficiency of Fe–Si–BAR is about 167 and 34 times than that of FeCP for the Cu2+ ions solution of 100 mg/L and 500 mg/L, respectively. Furthermore, the apparent reaction activation energy is calculated to be 18.7 and 19.4 kJ/mol for Fe–Si–BAR and FeCP, indicating that both the reactions of Fe–Si–BAR and FeCP are diffusion-controlled process. Microstructure investigations shown that loose product layer on the surface of the Fe–Si–BAR contribute to the high efficiency of Fe–Si–BAR in remediation of heavy metal-polluted water.

Efficient removal of antibiotics from water by highly crosslinked metal-alginate particles: Preparation, isotherms, kinetics, and microbiological assay

Improving removal of antibiotics in constructed wetland treatment systems based on key design and operational parameters: A review

Synergistically boosted non-radical catalytic oxidation by encapsulating Fe3O4 nanocluster into hollow multi-porous carbon octahedra with emphasise on interfacial engineering

Halloysite-based tubular nanorockets with chemical-/light-controlled self-propulsion and on-demand acceleration in velocity are reported. The nanorockets are fabricated by modifying halloysite nanotubes with nanoparticles of silver (Ag) and light-responsive α-Fe2O3 to prepare a composite of Ag-Fe2O3/HNTs. Compared to the traditional fabrication of tubular micro-/nanomotors, this strategy has merits in employing natural clay as substrates of an asymmetric tubular structure, of abundance, and of no complex instruments required. The velocity of self-propelled Ag-Fe2O3/HNTs nanorockets in fuel (3.0% H2O2) was ca. 1.7 times higher under the irradiation of visible light than that in darkness. Such light-enhanced propulsion can be wirelessly modulated by adjusting light intensity and H2O2 concentration. The highly repeatable and controlled "weak/strong" propulsion can be implemented by turning a light on and off. With the synergistic coupling of the photocatalysis of the Ag-Fe2O3 heterostructure and advanced oxidation in H2O2/visible light conditions, the Ag-Fe2O3/HNTs nanorockets achieve an enhanced performance of wastewater remediation. A test was done by the catalytic degradation of tetracycline hydrochloride. The light-enhanced propulsion is demonstrated to accelerate the degradation kinetics dramatically. All of these results illustrated that such motors can achieve efficient water remediation and open a new path for the photodegradation of organic pollutions.

Advanced biomaterials and alternatives tailored as membranes for water treatment and the latest innovative European water remediation projects: A review

Hierarchical porous tannic-acid-modified MOFs/alginate particles with synergized adsorption-photocatalysis for water remediation