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To improve the performance and solve the restrictions of UV/chlorine process (e.g., the narrow pH application range and high disinfection by-products (DBPs) formation), a Fe 2+ assisted advanced oxidation process with electrochemically generated chlorine (UV/E-Cl/Fe 2+ ) was proposed for carbamazepine (CBZ) degradation, which eliminated CBZ (5 mg/L) within 4 min under the optimal conditions. Compared with UV/electro-generated chlorine (UV/E-Cl) and anodic oxidation-chlorination/Fe 2+ (AO-Cl/Fe 2+ ) processes, the apparent first-order kinetics constant in UV/E-Cl/Fe 2+ increased by 2.56 and 3.18 times respectively, and the energy consumption was lower (1.15 kWh/m 3 -log). Simultaneously, the pH application range could be expanded to 9, and DBPs formed in this process were 17.1% less than those in UV/E-Cl. Through quenching tests, electron paramagnetic resonance (EPR) experiments, measurement of • OH concentration, quantification of methyl phenyl sulfoxide (PMSO) and benzosulfone (PMSO 2 ) and processes comparison, possible CBZ degradation pathways and mechanism of UV/E-Cl/Fe 2+ were proposed, in which Fe(IV) played the dominant role in the early stage, while the production of radicals (i.e., • OH and Cl • ) was enhanced with the increase of chlorine generation, accelerating the CBZ removal. Furthermore, this process demonstrated wide application prospect in treating various contaminants and real wastewaters. In conclusion, this study offers an effective and energy-efficient method for organic pollutants degradation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

[Display omitted] • A salt-resistant solar evaporator inspired by the mangrove trees was fabricated. • The hierarchical channels of loofah sponge offer abundant escape channels for solar steam. • High chemical potential of contained Na+ in sodium polyacrylate hydrogel leads to Donnan effect. • The mechanism of solar desalination mechanism based Donnan effect was proposed systematically. • Efficient solar evaporation performance is realized even for concentrated brines. Solar desalination is considered an efficient way to alleviate the global shortage of freshwater resources. However, the salt accumulation on the surface of solar absorbers drastically reduces light absorption and steam evaporation efficiency, especially in highly concentrated brines. Herein, inspired by the salt rejection mechanisms of the mangrove trees, a sodium polyacrylate carbonized loofah (PAAS-CLF) was designed using the biomass porous loofah sponge as the matrix, modified with sodium polyacrylate (PAAS) hydrogel coating for solar-driven desalination. The loofah sponge coated PAAS hydrogel as a substrate could obtain a naturally high porosity. Moreover, relying on the negatively charged PAAS hydrogel rich in –COO– groups, it could confine Na+ to induce the Donnan effect, thus reducing the diffusion of salt ions into the water supply layer and avoiding salt accumulation fundamentally. The PAAS-CLF had high water evaporation rates of 1.83 kg m−2h−1 with an efficiency of 94.54% attained under 1 sun. More notably, the evaporator maintained stable water evaporation rates over 1.45 kg m−2h−1 in salt water with a broad range of salinity (35–200 g kg−1), and no salt accumulation was observed during the long-time evaporation. Therefore, this work provides an approach of the flexible application using environmentally friendly biomass sponge composite polyelectrolyte hydrogel for salt-resistant evaporator in solar desalination and concentrated brine treatment. [ABSTRACT FROM AUTHOR]

A possible mechanism for TCAA degradation in C-FeZIF/PMS system was then proposed. [Display omitted] • Graphene-based catalyst was established with Fe/Co and nitrogen doping. • 1O 2 was the main active species produced in the C-FeZIF/PMS system. • •SO 4 and •OH radicals assisted the catalytic process to a certain extent. • The combined radical and non-radical processes decomposed organic pollutants. Integrating transition-metal and nitrogen into carbon-based materials have been attracted considerable attention in peroxymonosulfate (PMS) activation, but it is a great challenge to establish strong interactions between metal species and graphene. Here, we established metal–organic frameworks (MOFs)-hydrogels which acted as templates to form a family of FeCo/graphene aerogels (C-FeCo, C-CoMIL and C-FeZIF). The C-FeZIF, which co-doped Fe/Co and nitrogen into graphene aerogel, exhibited the most regular and stable metallic frameworks, the best crystallization and biggest pore sizes; it also showed the highest efficiency and stability in PMS catalysis for trichloroacetic acid (TCAA) degradation among these aerogels. By comparative analysis on different catalysis conditions (including catalyst dosage, PMS concentrations and reaction pH), 1 g/L C-FeZIF with 4 mM of PMS reacting under pH 5 showed to be the optimum conditions with an 81.2% removal of TCAA in 160 min. Meanwhile, the C-FeZIF/PMS system also performed well in TCAA degradation within a wide pH range from 3 to 9. Radical analysis suggested that 1O 2 was the main active species produced in the C-FeZIF/PMS system, while both SO 4 •- and •OH radicals assisted the catalytic process to a certain extent. The synthesis process is environmentally friendly, easy to carry out, safe and stable with no secondary pollution, which could be scaled up easily for catalyst preparation for water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional Janus solar evaporator was developed. • It exhibited synergic photocatalysis and solar-driven interfacial steam generation. • The JPMS presented effective desalination without the risk of salt accumulation. • Excellent water purification capacity. The expeditious advancement of solar-driven interfacial steam generation by utilizing renewable and free solar energy is a promising strategy for remedying the water crisis. However, salt accumulation on solar evaporators and organic pollutants increases in the remaining bulk water block its commercial potential for practical applications. Herein, a Janus solar evaporator was designed by using a commercialized melamine sponge as the matrix, followed by PDMS modification and deposition of Chinese ink, and TiO 2 nanoparticles. The Janus photothermal melamine sponge (JPMS) was designed with containing a hydrophobic salt resistance layer, and a composite photothermal and photocatalysis layer from top to bottom. The applicability of the developed JPMS was systematically investigated for water evaporation, photocatalytic degradation, desalination as well as wastewater treatment. The JPMS exhibits an evaporation rate of 1.49 kg m-2h−1 with a corresponding efficiency of 93.54% under 1 sun illumination. Notably, the JPMS also exhibits the high efficiency of synergic photocatalysis for organic pollutants and acquires an excellent salt rejection capability. Integration of SISG, photocatalytic, and salt resistance may be viewed as a prospective avenue for water purifying. [ABSTRACT FROM AUTHOR]