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• The TENG has excellent mechanical tensile properties (487%), softness and mechanical match to the skin. • The TENG can be used normally under extreme conditions of -80 to 80 °C. • Self-powered Band-Aids can be used for sports health monitoring. • Self-powered Band-Aids can create electrical current to stimulate diabetic wounds with the goal of accelerating repair. Patients with diabetes who have difficulty healing wounds due to high blood sugar, persistent inflammation, oxidative stress, bacterial infections, vascular damage, and diabetic peripheral neuropathy and long-term medication can also place a heavy burden on the patient's body and economy. Traditional dressings and skin bioelectronics have single function, mechanical mismatch, high price and challenging usage, which seriously limit their wide clinical application. Here, we have developed a wearable, low-cost and self-powered Band-Aid with PVA/Ecoflex/MXene/borate/gly(glycerol) hydrogel and Ecoflex. It has excellent electrical output performance, soft texture and stable properties, and can maintain excellent performance under extreme conditions. We apply it to the repair of diabetic wounds and monitor human activity as a motion sensor. In vitro and in vivo data show that self-powered Band-Aid can accurately monitor human movement and accelerate diabetic wound repair by promoting cell proliferation and migration, collagen deposition and angiogenesis. The self-powered Band-Aid that we created demonstrates its tremendous potential not only as a motion sensor, but also as a novel technique of promoting refractory wound healing in medicine. [ABSTRACT FROM AUTHOR]

[Display omitted] • Intrinsic properties of MABRs and the corresponding technical advantages are reviewed. • MABR technology is a promising option for in-situ upgrading WWTPs by enhancing SND. • A deep understanding of MABRs for supporting the PN/A process is provided. • Future research on MABRs based on interdisciplinary integration are suggested. Membrane aerated biofilm reactors (MABRs) represent energy-efficient technology for biological nitrogen removal (BNR) that brings wastewater treatment plants (WWTPs) closer to carbon neutrality. In a MABR, gas-permeable hydrophobic membranes supply oxygen and serve as carriers for biofilm attachment. Given the importance of sustainable nitrogen removal from wastewater, MABR technology has attracted significant attention in recent years, leading to advances in theoretical understanding and practical applications, particularly in coupling with novel BNR processes (e.g., simultaneous nitrification/denitrification [SND] and partial nitritation/anaerobic ammonium oxidation [PN/A]). This review summarizes the intrinsic characteristics of MABRs (e.g., bubbleless aeration, counter diffusion) and their technical advantages (e.g., energy efficiency, low greenhouse gas and volatile organic compound emissions, compatibility with novel BNR processes). We also describe the robust SND performance of MABRs and the implications for upgrading existing WWTPs. Additionally, we systematically present the technological breakthroughs in the integration of the PN/A process into MABRs. Finally, we provide insights into the applicability of novel BNR-based MABRs in efficient WWTP construction and discuss future research directions of MABR technology based on the interdisciplinary integration of materials science, information technology, and biotechnology. This review contributes to a deeper understanding of MABR applications in wastewater nitrogen removal and provides guidance for further developments of this cost-efficient technology to achieve sustainable energy performance in future WWTPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hf-porphyrin MOF with missing linker defects promoted NFX removal in high saline water. • Missing-linkers defects facilitated the photoinduced charge transfer (PICT). • Missing-linkers defects captured anions to trigger ligand − metal charge transfer. Treatment of saline wastewater with advanced oxidation technologies has been an urgent challenge due to the inhibitory effect of coexisting ions on reactive oxygen species in real wastewater. Herein, monocarboxylic acids with varying acidity coefficient were employed to modulate the number of missing-linker defects in Hf-porphyrin MOFs (Hf-TCPP-X) to regulate their performance in removing norfloxacin (NFX) from complex aqueous matrices. The missing-linker defect density in Hf-MOFs promoted the removal efficiency of NFX from 8.5 % to 93.6 %. In various anion surroundings, the adsorption and photocatalysis performance of Hf-TCPP-FA with missing-linker defects was enhanced significantly. Quenching tests and the electron paramagnetic resonance (EPR) exhibited that O 2 ∙−, 1O 2 , and ∙OH dominated NFX removal and their content rising in Hf-TCPP-FA/NaCl/visible-light (Hf-TCPP-FA/NaCl/vis) system. Density functional theory (DFT) calculations displayed that the adsorption energy of Hf-TCPP-FA for NFX decreased from −12.128 eV to −19.157 eV after adding Cl−. The missing-linker defects of catalysts facilitated the photoinduced charge transfer (PICT) under the visible-light irradiation and increased the number of active sites (Hf) in high salinity water. Additionally, favorable NFX removal efficiency could be sustained in Hf-TCPP-FA/visible-light (Hf-TCPP-FA/VIS) system from a wide pH range of aqueous solutions, high coexisting ion concentrations, and in the actual water matrices, and be performed well in cycling tests. This work suggests a promising route to tailor MOF-based photocatalysts by defect engineering and thus improve the removal performance of contaminants in highly saline water. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOFs with a low ratio of H 2 TCPP to monocarboxylate displays the best BPA removal performance. • The contents of O 2 ∙-, 1O 2 and ∙OH are enhanced by high salinity. • Coexisting salt ions increase the density of states near the Fermi level, boosting the transfer of electrons. • Coexisting salt ions prevent the recombination of photogenerated electrons and holes. The treatment of wastewater containing high salinity has been a pressing challenge due to the inhibition of reactive oxygen species by co-existing ions in the actual wastewater. In this work, four Zr 6 O 8 -porphyrinic MOFs (PCN-223, PCN-224, PCN-225, and MOF-525) with different topologies were selected to investigate their performance and mechanisms for the removal of contaminants from hypersaline waters in a visible photocatalytic degradation system. The results showed that the molar ratios of monocarboxylates, ligands, and Zr of the porphyrin-MOFs led to variations in the porosity, pore size distribution, crystal defects, and surface electrical properties of the as-obtained MOFs, resulting in differences in the adsorption and photocatalytic degradation performance of the materials towards bisphenol A. In-situ electron paramagnetic resonance (EPR) and quenching experiments showed that high salt surroundings can significantly increase the levels of O 2 ∙-, 1O 2 and ∙OH in Zr 6 O 8 -porphyrin-MOFs/visible-light systems. DFT calculations explain that the presence of anions not only promotes the adsorption of BPA by MOFs but also facilitates the conduction of photogenerated electrons and prevents the recombination of photogenerated electrons and holes during the photocatalytic process. The super-exchange charge transfer mechanism was shown to play a key role in the Zr 6 O 8 -porphyrin-MOFs/visible-light system, thereby accelerating the degradation of pollutants in high-salinity wastewater. The catalytic system can maintain consistent contaminant degradation efficiency over a wide pH range, with high concentrations of co-existing ions and in real water matrices. In addition, the catalyst also exhibits excellent stability and reusability. This work provides new insights into the application of porphyrin MOFs based visible photocatalytic processes for the treatment of highly saline wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cobalt adsorbed on ferric sludge was recycled to create bimetallic catalyst via a facile solvothermal method. • Co/Fe nanocomposites derived from ferric sludge (CoFe@FS) exhibited an excellent performance toward PMS. • SO 4 •−, •OH, O 2 •− and 1O 2 were produced from PMS activation by synergetic effect of Co and Fe on the catalyst surface. • The possible degradation mechanism of CIP is proposed based on DFT calculations and LC/MS analyses. • This is a cost-effective method to achieve "treating wastewater by waste residuals". Ferric sludge, generated during drinking water purification process, can be considered as a promising support with potential iron resource. Herein, magnetic bimetallic Co/Fe nanocomposite derived from ferric sludge (CoFe@FS) was created via a facile solvothermal treatment and employed as an efficient peroxymonosulfate (PMS) activator for the elimination of antibiotic ciprofloxacin (CIP) in water. CoFe@FS exhibited nano-sphere structure with the composites of CoO, CoFe 2 O 4 and SiO 2 crystals and presented excellent catalytic performance with 97.3% removal efficiency of 10 mg/L CIP within 15 min. Sulfate radicals (SO 4 •−), hydroxyl radicals (•OH) superoxide radicals (O 2 •−) and singlet oxygen (1O 2) all contributed to CIP degradation, and SO 4 •− functioned as the dominant reactive species in this activation system. CoFe@FS composite exhibited great reusability due to the strong Co/Fe-Si interaction and was able to regenerate by a simple solvothermal process. The CIP degradation mechanism in the CoFe@FS/PMS system were also proposed based on density functional theory (DFT) calculations and analysis of intermediate products. Overall, the magnetic Co/Fe bimetallic catalyst derived from ferric sludge could be employed as high-efficiency and low-cost candidate for the degradation of refractory organic contaminants. This work not only provides a promising reclamation strategy of water treatment waste from ferric sludge to high-effective catalyst, but also clarifies the mechanisms of PMS activation and CIP degradation. The more stable bimetallic CoFe catalysts derived from waste sludge need to be developed in the future study to relieve the occurrence of metal leaching. [ABSTRACT FROM AUTHOR]

[Display omitted] • Copper cation was introduced to FeSx to obtain Cu-SZVI with higher durability. • Cu-SZVI exhibited a remarkable pH tolerance to Cr(VI) sequestration. • Doping copper optimizes reactivity of SZVI and enhances electronic conductivity. • Cu-SZVI enhanced removal capacity of Cr(VI) compared with SZVI. Sulfidation of zero-valent iron (SZVI) is an important means to greatly inhibit the formation of inert hydr/oxide and improve the overall reactivity in pollutant removal reactions, which is mainly benefiting from the formation of FeS x layer on surface of the zero-valent iron (ZVI). However, FeS x phase can act as reducing reagent in the treatment of pollutants, resulting in inevitable consumption. Considering that, copper cation was introduced to the FeS x phases to prepare copper-doped sulfides with improved durability. In this study, we successfully prepared copper-doped SZVI (Cu-SZVI). The composition and structure have been clearly confirmed by a combination of several techniques, including Raman spectroscopy and X-ray powder diffraction. Cu-SZVI exhibits a superior sequestration reaction to remove Cr(VI) with higher removal capacity of 82.93 mg/g, with the comparison of SZVI (57.54 mg/g) and ZVI (8.23 mg/g). Moreover, Cu-SZVI possesses better operational pH tolerance and longer lifetime of usage, which makes it particularly attractive to large-scale environmental applications. This work proposes a new way to modify SZVI by doping a secondary cation, which can be used to further explore new SZVI materials based on specific needs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Alkaline pH values greatly enhanced disintegration and VFA production of MBR sludge. [•] The optimal condition for VFA production was under pH 11.0 and digestion time 4d. [•] High pH stimulated organic matter transfer from the inner to the outer of microbes. [•] Bound EPS were involved in organic matter transformation and VFA production. [ABSTRACT FROM AUTHOR]

• Porphyrin-MOF greatly improved its performance in BPF removal under visible light in complex environments. • Photo-generation of ∙OH is enhanced by high salinity in PCN-223/visible-light system. • Possible degradation mechanism and pathway of BPF were proposed. • Toxicity of BPF was reduced in the PCN-223/visible-light system. The efficient degradation of organic contaminants in practical water treatment is a challenge for advanced oxidation processes via such as semiconductor photocatalysis due to interference from the inhibiting influence due to the reactions between radicals and coexisting anions in the actual water column. Herein, a porphyrinic zirconium metal–organic framework (PCN-223) is used in a visible light system to effectively decompose bisphenol F (BPF) in saline water. The PCN-223/visible-light system can effectively resist the influence of environmental coexisting anions and natural organic matter (NOM), thus demonstrating excellent performance in decomposing pollutants. Furthermore, the catalytic system is able to maintain stable contaminant degradation over a wide pH range and in five water matrices. Coexisting anions promote the conductivity of electrons by forming ionic bonds with Zr, which enhances light-induced electron transfer under visible light. This work illustrates the mechanism and conditions under which porphyrin-MOF can resist high salt environments in photocatalysis, and provides a new perspective on the practical application of photocatalysis to overcome complex environmental disturbances. [ABSTRACT FROM AUTHOR]

Abstract: An upflow dynamic membrane separation (DMS) process was developed for organic matter recovery from low-strength municipal wastewater. During the operation of 300days, 81.6% of organic matter recovery rate on average was achieved at a high membrane flux of 60L/(m2 h). Chemical analyses and batch assays revealed that the recovered organic matter (ROM) had larger carbon to nitrogen mass ratio (C/N) and higher fermentation potential compared to the waste activated sludge. The transformation of the organic matter occurred in the DMS process, which was related to the polyferric sulfate (PFS) coagulation, anaerobic metabolism and membrane retention. The recovery of soluble organic matter was facilitated by the coagulation, and the transformation was observed in the sludge zone due to the anaerobic metabolism. Although the dynamic membrane was less efficient to remove the small molecules, it allowed a sound retention of particulate fractions and biopolymers, enabling a relatively high ROM recovery in the DMS process. Furthermore, the net operation expenditure for the novel wastewater treatment paradigm employing the DMS process was about 0.24kWh/m3, much lower than that (1.10kWh/m3) for the conventional membrane bioreactor treatment technology. These results indicated that the upflow DMS process was a promising approach for sustainable wastewater treatment. [Copyright &y& Elsevier]

Abstract: In this study, polyacrylonitrile (PAN) flat-sheet membranes were prepared using phase inversion method for the wastewater treatment by membrane bioreactor (MBR). Twelve processing factors in the membrane preparation were investigated by Plackett–Burman design (PBD) in order to prepare high-performance membranes. Test results showed that none of the twelve processing factors had a significant effect on membrane pore size. The casting thickness, non-woven fabric type and casting speed were found to have substantial negative effects on the pure water flux values, and were identified as the significant factors determining the membrane pure water flux. It was also found that the non-woven fabric type, casting speed and casting thickness had significant positive effects on the fouling rate. Moreover, the model using membrane fouling rate as a response value was more credible and in good linear correlation within the tested range. [Copyright &y& Elsevier]

Abstract: A new pathway was explored in order to gain insights into the role of biopolymers in sludge characteristics and membrane fouling. The biopolymers were discharged from a membrane bioreactor (MBR) using a unique design (called as dual-MBR in this study). The variations of soluble microbial products (SMP), extracellular polymeric substances (EPS), sludge surface charge, particle size and dewaterability were analyzed in the dual-MBR after the discharging of biopolymers from the system. It was found that carbohydrates in SMP, proteins in SMP and humics in SMP were decreased in the dual-MBR compared to the control-MBR. Gel filtration chromatography (GFC) analysis showed that the substances with macromolecular weight in SMP were reduced in the dual-MBR. Three-dimensional excitation–emission matrix (EEM) fluorescence spectra demonstrated that the aromatic protein-like substances in SMP were also lowered in the dual-MBR. The neutral hydrophilic (HPI-N) fraction in SMP, which was found to have larger molecular weight distribution and stronger fouling potential compared to the rest fractions, was significantly reduced in the dual-MBR. The exclusion of biopolymers from the dual-MBR also resulted in the decrease of the bound EPS and the reduction of proteins in bound EPS, which consequently caused the decrease of sludge surface charge, the increase of sludge flocs and the improvement of sludge dewaterability. The above changes induced by the exclusion of biopolymers can explain why the trans-membrane pressure in the dual-MBR exhibited a slower increase rate compared to the control-MBR. This study offered an evaluation of the contribution of biopolymers to sludge characteristics and membrane fouling through a different angle from previous publications. [Copyright &y& Elsevier]

Abstract: Two distinct fouling layers, i.e., a gel layer and a sludge cake layer were observed in two MBRs operated under same constant fluxes but different aeration rates. The formation mechanisms and properties of the two fouling layers were systematically analyzed. It was found that the gel layer had lower porosity and higher specific resistance (α c ) compared to the sludge cake layer. The mean particle size of the gel layer was smaller than that of the sludge cake layer. Soluble microbial products (SMP) were found to be the major soluble organic materials in both fouling layers. Mg, Ca and Al were the major inorganic elements in solid state of the foulants, and the monovalent elements such as Na and K were mainly detectable in the soluble component of the foulants. SMP and tightly bound extracellular polymeric substances (EPS) of both fouling layers featured macromolecular characters. The molecular weight (MW) of gel foulants was larger than that of cake foulants. The loosely bound EPS and the fouling layers had very similar MW distribution profiles. Only the peaks associated with protein-like fluorophores were detectable in gel foulants, while besides the protein-like materials the humic acid-like substances were present in sludge cake foulants. [Copyright &y& Elsevier]

Abstract: Two submerged anoxic/oxic membrane bioreactors (MBRs) were operated in parallel under same conditions but different aeration intensities. The Aeolosoma hemprichi and Tubificidae proliferated in the MBR operated under high aeration intensity but were never observed in the MBR with low aeration intensity. Sludge yield coefficient, sludge physicochemical characteristics and filtration performance in the two MBRs were systematically investigated. Results showed that the presence of aquatic worms decreased the total phosphorus removal efficiency while it had no impacts on chemical oxygen demand and nitrogen removal. High aeration intensity could decrease the floc size and increase dispersed bacteria population, thus providing more feed for the worms. The worm growth led to a reduction of the sludge production, an increase of soluble microbial products, an improvement of sludge settleability and a deterioration of sludge dewaterability. The excess growth of worms resulted in a higher membrane fouling rate in the MBR. [Copyright &y& Elsevier]

Abstract: An anaerobic dynamic membrane bioreactor with a high flux of 65L/(m2 h) was used to treat municipal wastewater. Particle size distribution, scanning electron microscopy, gel filtration chromatography (GFC), and three-dimensional excitation–emission matrix (EEM) were used to investigate the components of the cake layer formed on the membrane surface and the interception effect of the dynamic membrane. Test results showed that the dynamic membrane was formed by suspended solids (SS) in the settling zone and the soluble contents such as soluble microbial products (SMP) and extracellular polymeric substances (EPS). According to the index of SS/cake volume, the formation of dynamic membrane can be divided into three stages, i.e., the formation of separation layer, the stable growth stage, and the fouling stage. The accumulation rates of SS, SMP and EPS were of some differences at each stage. The secondary membrane was not entirely formed until the 7th day, and the dynamic membrane demonstrated a weak interception effect of dissolved organic matters after the 20th day. From EEM and GFC analyses of SMP in the cake layer, it was found that the fluorescence intensity ratio of Peak B/Peak A in the EEM fluorescence spectra had a similar changing tendency with large molecules of MW>5000kDa. They both increased with operation time before the 20th day, probably due to the soluble by-products secreted by the microorganism in the cake layer. [Copyright &y& Elsevier]

Abstract: Traditionally, the chemical cleaning is unanimously considered to be an effective means to restore membrane permeability. However, the chemical solutions can also be responsible for changes in membrane properties and thus affect the life-span of membranes. The aim of this study was to gain a better understanding of the effect of sodium hypochlorite cleaning solutions on the changes of physiochemical characteristics of microfiltration (MF) flat sheet membranes made from polyvinylidene fluoride (PVDF). A pilot-scale MBR was operated for 63 d and frequent and high dose sodium hypochlorite cleaning was carried out. The properties of the original and cleaned membranes were compared by pure water flux evaluation, contact angle measurement, mechanical testing, and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra analysis. Effective removal of the foulant from the membrane surface resulted in more severe fouling. The pure water flux decayed faster with the extension of operation time and the membrane became more and more hydrophilic. The deterioration of ultimate tensile strength and the improvement of the ultimate elongation of membranes showed that membrane became more weak and flexible after hypochlorite cleaning. The results of ATR-FTIR indicated that the sodium hypochlorite cleaning had no vital damage to the chemical structure of PVDF membrane, but exerted impacts on its surface properties. [ABSTRACT FROM AUTHOR]

Abstract: Two identical submerged membrane bioreactors (MBRs) for synthetic wastewater treatment were operated in parallel under different dissolved oxygen (DO) levels for over 3 months in this study. The digital biological microscopy, particle size distribution (PSD) analysis, gel filtration chromatography (GFC), three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy, and column chromatographic method, etc. were used to identify the difference between bulking sludge (BS) caused by filamentous bacteria (low DO operation, about 0.4mg/L) and normal sludge (NS) (high DO operation, about 4.0mg/L) and to obtain a comprehensive insight into the behaviours of filamentous bacteria in MBRs. Test results showed that the MBR with bulking sludge (BS-MBR) exhibited a better filtration performance and a reduced membrane fouling compared to the MBR with normal sludge (NS-MBR). It was found that the mitigation of membrane fouling by the abundant filamentous bacteria in the BS-MBR could be attributed to the larger PSD, lower hydrophobic contents in SMP, and the retention effects of a special fouling layer induced by filamentous bacteria. [Copyright &y& Elsevier]

Abstract: Membrane foulants were systematically characterized in an anaerobic membrane bioreactor (AnMBR), in which non-woven fabric was used as the membrane material. In this study, three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy, gel filtration chromatography (GFC), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and energy-diffusive X-ray (EDX) analyzer were used to analyze the membrane foulants. The results indicated that the organic substances with fluorescence characteristics in the extracellular polymeric substances (EPS) extracted from the membrane foulants were identified as proteins and visible humic acid-like substances by EEM technology. The GFC analysis exhibited that the EPS had much broader distributions of molecular weight (MW) and a larger weight-average molecular weight (M w) compared with the influent wastewater and the effluent. Proteins and clay materials were also identified in the fouling layer by the FT-IR analysis. The examination by EDX demonstrated that Mg, Al, Ca, Si, and Fe were the major inorganic elements in the fouling cake. Furthermore, the results suggested that bridging between deposited biopolymers and inorganic compounds could enhance the compactness of fouling layer. During the operation of AnMBR, the protein-like and visible humic acid-like substances, which were main components of the organic matters with fluorescence characteristics in the influent, were partly removed. And the large MW organics (>4000Da) in the influent were partly metabolized into low MW organics by microorganisms combined with the separation function of the cake layer and the membrane pores. [Copyright &y& Elsevier]

Abstract: The distribution and transformation of molecular weight (MW) of organic matters in a pilot-scale submerged membrane bioreactor (MBR) and a conventional activated sludge (CAS) process was studied in order to better understand organic pollutant behaviours and removal mechanisms in the two processes. Gel filtration chromatography (GFC) images of the CAS process showed that the influent wastewater had relatively large MW molecules and a narrow MW distribution while the dissolved organic matters (DOM) in the anaerobic, anoxic, oxic basins and the effluent water demonstrated a broad MW distribution. MW distribution in the MBR system illustrated that the organic matters with high MW molecules were degraded into relatively low MW organic substances, whereas DOM in the oxic basin had a little part of high MW molecules produced by microorganisms during the metabolism of substrates. There is a lack of those high MW molecules in the effluent water due to the retention of the macromolecules by the membrane. Test results also showed that in both the CAS process and the MBR the majority of molecules in the influent wastewater with MW between 100kDa and 500kDa were mainly transformed into the molecules with MW between 10kDa and 100kDa. [Copyright &y& Elsevier]

• The central nitrogen vacancy polymerized carbon nitride (FCN) was prepared by hydrothermal calcination. • The photocatalytic degradation rate of TC-HCl by FCN-5 is 0.04751 min−1, which is 2.2 times that of the original CN. • Two new possible degradation paths of TC-HCl were proposed. • The photocatalytic degradation mechanism of •O2– and 1O2 radical of TC-HCl was introduced. • The ecological safety of the restored water body was verified by plant experiment and TEST toxicity assessment software. Carbon nitride had unique structure and electronic properties, and had wide application prospects in the field of photocatalysis. However, the rapid photogenerated carrier recombination efficiency and low photocatalytic activity limit its use. Defect construction was considered to be an effective strategy to improve the photocatalytic activity of carbon nitride. In this paper, nitrogen defective carbon nitride was prepared by formic acid assisted pyrolysis. The formic acid was used to regulate the top atoms and effectively shorten the band gap. Second, the gas released during pyrolysis contributed to the construction of porous structures. SEM, TEM, BET, XPS were used to confirm the presence of nitrogen defective sites. When it was used to photocatalyze the degradation of tetracycline, the main antibiotic pollutant in Dongting Lake, the degradation rate of 95.1 % was achieved in 60 min. Compared with conventional carbon nitride, the degradation rate constants were 0.04751 min−1 and 0.02110 min−1, respectively. Compared with CN, the degradation rate constant of FCN-5 was increased 2.2 times. The photocatalytic degradation activity was verified by photochemical experiments. •O 2 – and 1O 2 active radicals dominate the photocatalytic degradation process. The ecological safety of Dongting Lake water samples repaired by defective carbon nitride has been confirmed, and the toxicity of antibiotics to the germination and growth of legumes has been effectively alleviated. Five cycles of the experiments ensured that the material can be reused. The above work provided reference and basis for the development and design of defective carbon nitride for water body restoration in Dongting Lake basin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-anchoring and N-doping were achieved simultaneously using CMC hydrogel. • Graphitic N and Fe x N y facilitates the adsorption of PMS and electron transfer. • The Fe@N-CNs/PMS system showed excellent salt tolerance. • Less harmful products were generated during SMX degradation. • Efficient ARG inactivation was achieved. An environmentally friendly Fe@nitrogen-doped carbon nanocomposite catalyst (Fe@N-CNs) was prepared via a facile and economical process using carboxymethyl chitosan (CMCs) hydrogel as a template to achieve Fe-anchoring and N-doping simultaneously for peroxymonosulfate (PMS) activation to efficiently degrade sulfamethoxazole (SMX). The "core–shell" structure of Fe@N-CNs displayed that Fe nanoparticles identified as Fe 3 C and Fe 3 N were encapsulated in nitrogen-doped carbon nanosheets. The formation of Fe x N y sites and the high content of graphitic N obtained from CMCs facilitated the catalytic reaction. With excellent catalytic activity to achieve complete degradation of SMX in less than 10 min, Fe@N-CNs/PMS system also exhibited stable catalytic degradation efficiency over a wide pH range (3.0–9.0) and under high-salinity conditions. Singlet oxygen was identified as the dominant reactive species in catalytic oxidation and played a vital role in the non-radical pathway. The potential SMX degradation pathway and mechanism in the Fe@N-CNs/PMS reaction system were proposed according to DFT calculations and product detection results. Quantitative structure–activity relationship (QSAR) prediction verified the efficient elimination of SMX degradation products toxicity. Moreover, the Fe@N-CNs/PMS system was also confirmed to be effective towards the inactivation of antibiotic-resistant bacteria (ARB) and antibiotics resistance genes (ARGs). [ABSTRACT FROM AUTHOR]

Highlights: [•] Aquatic worm predation was efficient to enhance power production from sludge. [•] The maximum power output was increased by 44.4% compared to the control. [•] Predation improved the anode performance of rotating-cathode microbial fuel cells. [•] Hydrolysis of particulate organic matter in sludge was accelerated due to predation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nano-TiO2 was an excellent adsorbent for virus removal in drinking water. [•] The adsorption followed Freundlich isotherm and pseudo second-order rate equation. [•] The PAN (0.05μm) membrane had higher removal efficiency than PVDF (0.20μm). [•] The coupling system (nano-TiO2-membrane) increased the removal efficiency of virus. [•] Coupling system can achieve the effective separation and recycle of nano-particles. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-efficient removal of TC was achieved in the E-PCF-PMS system. • PCF membrane anode with good conductivity and safety activates PMS efficiently. • PMS could retard the anodizing of PCF and prompt the generation of 1O 2. • The contribution of 1O 2 in the E-PCF-PMS system was as high as 85.7%. • E-PCF-PMS system exhibits excellent mineralization and anti-interference ability. A flow-through peroxymonosulfate (PMS) electro-activation system with a polyacrylonitrile-based carbon fiber (PCF) membrane anode (denoted as E-PCF-PMS system) was developed. The introduction of the PCF membrane anode enabled the flow-through electrocatalytical system to achieve a remarkable tetracycline (TC) removal of 96.0 ± 0.2 % within 15 min, with a degradation rate of 0.273 min−1. Scavenging investigations revealed that singlet oxygen (1O 2) was the dominant reactive oxygen species for TC degradation in the E-PCF-PMS system, and this finding was confirmed by electron paramagnetic resonance tests. Potential degradation pathways of TC were identified according to the detected intermediates and calculations of density functional theory, and a decreasing trend in the toxicity of TC intermediates was discovered. Thanks to the 1O 2 -dominated pathway, the constructed E-PCF-PMS system could achieve efficient TC degradation under different concentrations of several common anions (Cl−, NO 3 −, HPO 4 2−, and HCO 3 −) and humic acid (HA). General applicability and reusability tests demonstrated the excellent practicability of the proposed system. The PMS electro-activation system offers a potential technique for high-efficient degradation of contaminants in water and wastewater. [ABSTRACT FROM AUTHOR]

• Supramolecular networks containing covalent and transient crosslinks were fabricated. • Multi-stimuli-responsive supramolecular networks showed high toughness, shape memory effect, and self-healing function. • UV light-healing approach provided a remote, on-demand, faster, and more efficient healing compared to direct heating. • The supramolecular polymers enabled the fabrication of the tough self-healing strain sensors. This work demonstrated heat- and light-responsive supramolecular networks having high toughness, shape memory and self-healing properties. The supramolecular networks were composed of covalent and transient crosslinks that were formed by crystalline poly(ethylene glycol) (PEG) and poly(ε-caprolactone) (PCL) and by 2-ureido-4-pyrimidone (UPy) supramolecular moieties. The resultant supramolecular networks realized exceptional mechanical performance such as tensile stress of 7.2 MPa and toughness of 25.2 MJ m−3. By utilizing the light-to-heat conversion capability of UPy moieties, the polymer films could be heated up to ~63 °C under UV light irradiation, which was sufficient to activate the temperature-dependent shape memory and self-healing properties. Consequently, supramolecular polymers were responsive to the heat as well as the light irradiation, and the latter resulted in faster and desirable shape memory effect. Furthermore, the direct heating and the photoeffect heating could enable the self-healing of the damage via dynamic reversibility of UPy units. It is noteworthy that the light-induced healing allowed remote activation, on-demand treatment, faster self-healing (1 min) and higher healing efficiency (86%) in comparison with direct heating. The tough self-healing materials enabled the fabrication of durable strain sensors with high toughness and electrical healing ability, indicating their great potentials in the flexible electronic field. [ABSTRACT FROM AUTHOR]

• The AgNPs was immobilized on TiO 2 with dopamine as a reducing agent and a binder. • TiO 2 /AgNPs hybride FO membranes were fabricated by eletrospinning. • Water flux of TFN membrane attained 56 LMH, much higher than commercial membrane. • TRGs permeation by TFN0.3 membrane was 1.29 times lower than that by TFC membrane. • TRGs on the transposons are more likely to penetrate the membrane. As antibiotic resistance genes have continued to spread, they have become a new research hotspot in the field of sewage treatment. Herein, the rejection of tetracycline-resistant genes (TRGs) in reclaimed water by forward-osmosis (FO) membranes, were modified by silver nanoparticles (AgNPs) anchored titanium dioxide (TiO 2), and investigated. The AgNPs were immobilized in TiO 2 with dopamine as a reducing agent and a binder. The composite FO membranes were obtained by interfacial polymerization with the electrospun-polysulfone/TiO 2 /AgNPs-composite nanofiber membranes. Results show that the thin-film nanocomposite membrane with 0.3 wt% TiO 2 /AgNPs-loading (TFN0.3) exhibited excellent physicochemical properties and performed prominently in regards to water flux, reverse salt flux, and antimicrobial activity. Moreover, rejection characteristics of five kinds of TRGs (tetA, tetC, tetM, tetO, and tetX) and the integrase gene of class 1 integrons (int1) by the as-prepared FO membranes were also studied. In the sample results, TFN0.3 had a better performance in rejecting TRGs and int1 than others. The rejection of TRGs by TFN0.3 under AL-FS (active layer-facing feed solution) and AL-DS (active layer-facing draw solution) mode were 28.53% and 24.48% higher than those using a pristine thin-film composite membrane, respectively. [ABSTRACT FROM AUTHOR]

• N/O-doped carbon nanosheets are derived from a high-carbon-yield poly(ionic liquid). • The 3D porous architecture is tuned via alkali ion exchange and in-situ activation. • Ion-matching pores and ion-transport paths work along for a maximized capacitance. • Pore-ion size compatibility achieves high energy density and high-voltage tolerance. Maximizing carbon capacitance in high-voltage electrolytes has gained increasing interests to resolve the low energy storage concern in supercapacitors. Yet the large ion sizes and high viscosity of such electrolytes greatly thwart their compatibility with the pore diameters of carbon electrodes, leading to sluggish charge transport and unsatisfied energy-power outputs. Herein, heteroatom-doped, hierarchical porous carbons are derived from a high-carbon-yield main-chain poly(ionic liquid) bearing NH 2 +: HSO 4 − ion pairs and rigid aromatic backbones, followed by tailoring the 3D porous architecture through alkali ion exchange and in-situ activation. The typical sample (PIL-RbC) has sheet-like geometry, electron-rich N/O heterogeneous dopants, and a vast adsorbing surface (3021 m2 g−1). More importantly, PIL-RbC with ion-matching pores (dominated at 0.80 nm) and ion-transport paths (>1 nm pores) shows a superb compatibility with 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid electrolyte, giving a maximized electrode capacitance of 228 F g−1 in a symmetric supercapacitor. The PIL-RbC-based device delivers a high energy density up to 119.4 Wh kg−1 at 397 W kg−1, and maintains 41.7 Wh kg−1 at a high power-output of 19.7 kW kg−1, along with a satisfactory tolerability (91% retention after 10,000 consecutive cycles at 4 V). This strategy sheds light on both synthesizing poly(ionic liquid)-derived heteroatom-doped porous carbons and matching well-designed carbon electrodes with high-potential electrolytes for integrated enhancements in supercapacitor performances. [ABSTRACT FROM AUTHOR]

• O, N, S-tridoped carbon is designed via a simple benzoquinone-thiourea route. • A 3.5 V ionic liquid gel electrolyte is engineered using gel polymer as a support. • A solid-state supercapacitor yields an ultrahigh energy density of 90.9 Wh kg−1. • The elaborated electrode and electrolyte can be extended to highly flexible device. Developing advanced electrodes and electrolytes are two basic strategies to boost the energy outputs of supercapacitors, but previous studies are generally constrained to the point where only one component is focused. Herein, we report the design of high-performance O, N, S-tridoped carbon (ONSC) electrodes and a high-voltage porous gel electrolyte to construct high-energy flexible solid-state supercapacitors. First, high-surface-area (2917 m2 g−1) ONSCs with enriched heteroatoms (14.85 wt%) are synthesized based on a novel and simple benzoquinone-thiourea route to achieve a superior electrochemical capacitive capability. Second, a highly porous gel polymer is utilized to support ionic liquid of 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF 4) for fabricating a 3.5 V ionogel electrolyte. The elaborated ONSC electrode and EMIMBF 4 gel electrolyte enable the resultant solid-state supercapacitor with an extremely energy supply of 90.9 Wh kg−1, along with excellent cyclability (91.6% over 10,000 cycles) and temperature robustness (0–80 °C). Besides, an assembled flexible solid-state device delivers an energy density of 76.6 Wh kg−1, and manifests high flexibility with 90% retention even under a bending angle of 180°. This work presents an electrode/electrolyte engineering principle to achieve highly efficient energy storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel reactive electrochemical ceramic membrane (RECM) system was designed. • RECM system has dual functions of membrane filtration and contaminant degradation. • rTNA/SnO 2 -Sb/PbO 2 anode has excellent electrochemical property, stability and safety. • RECM system can efficiently and sustainably eliminate enrofloxacin from wastewater. A novel reactive electrochemical ceramic membrane (RECM), assembled by ceramic membrane and reduced TiO 2 nanotube arrays (rTNA) based PbO 2 membrane anode with a Sb-SnO 2 interlayer (rTNA/Sb-SnO 2 /PbO 2), was developed in this study with the dual functions of low-pressure membrane filtration and efficient removal of antibiotics from wastewater. Compared with Ti/Sb-SnO 2 and rTNA/Sb-SnO 2 membrane anodes, rTNA/Sb-SnO 2 /PbO 2 anode exhibited higher oxygen evolution potential, larger active surface area and promising electrochemical stability, owing to the introduction of rTNA structure and PbO 2 layer. The rTNA/Sb-SnO 2 /PbO 2 RECM also achieved a higher electrochemical degradation performance than Ti/Sb-SnO 2 and rTNA/Sb-SnO 2 RECMs, as well as a lower energy consumption. The antibiotic enrofloxacin (ENR) removal of the rTNA/Sb-SnO 2 /PbO 2 RECM in the flow-through mode was 5.4 times higher than that in the flow-by mode. These results were ascribed to the improved mass transfer of ENR towards anode surface and reactive oxygen species (i.e., H 2 O 2 , O 2 −, and OH) production. According to theoretical computations and the detection results of intermediates, the degradation pathway involved the defluorination, hydroxylation, decarboxylation, and breakage of quinolone and/or piperazine rings of ENR under the attack of hydroxyl radicals in the RECM system. The findings demonstrated the application potential of the rTNA/Sb-SnO 2 /PbO 2 RECM in removing ENR from wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • AMPs/alginate multilayers were constructed on membranes via LbL self-assembly. • The modified membranes showed enhanced hydrophilicity and antimicrobial ability. • The hydrogel network enabled the membrane to reduce the release rate of AMPs. • Long-term tests showed lasting antibiofouling property of the modified membrane. Biofouling remains to be one of major obstacles for membrane-based technology in water and wastewater treatment, calling for the development of antibiofouling membranes. For the traditional release-killing strategy, uncontrollable release of biocides and thus a short lifetime as well as the potentially environmental risk are thorny issues for the modified membranes. Herein, hydrophilic hydrogel multilayers with controllable thickness at nanometer scale on a poly(vinylidene fluoride) (PVDF) microfiltration membrane were constructed via layer-by-layer (LbL) self-assembly of non-drug-resistant antimicrobial peptides (AMPs) and alginate. The AMPs/alginate multilayers modified membranes exhibited enhanced hydrophilicity, well-controlled pore size distribution and prominent antimicrobial ability against Escherichia coli and Staphylococcus aureus. As the number of multilayers of alginate increased, both initial and steady release rate of Ponericin G1 reduced; in particular, the AMPs/alginate modified membranes with fifteen multilayers (MSA 15) had the slowest release kinetics (i.e., an initial release rate of 1.79 ± 0.07 μg/cm2 d and a steady release rate of 0.55 ± 0.03 μg/cm2 d), resulting in about 60% less release compared with the AMPs/alginate modified membranes with five multilayers (MSA 5). Long-term antibiofouling tests showed that the AMPs/alginate modified membranes with ten multilayers (MSA 10) exhibited a significantly reduced transmembrane pressure increase rate of 0.81 ± 0.01 kPa/d which was much lower than that of the control membranes (1.80 ± 0.20 kPa/d), mainly attributed to the antibacterial activity imparted by the lasting release of AMPs and competing membrane basic properties. Furthermore, the AMPs/alginate multilayers modified membranes revealed high stability suffering from long-term operation and chemical cleaning cycles. The novel AMP/alginate-incorporated modifying method provides a new dimension to enhance antibiofouling performance of membranes for water and wastewater treatment. [ABSTRACT FROM AUTHOR]

We develop a novel self-doped and self-template strategy to synthesize N, S doped porous carbon nanosheets (N/S-HCSs) by pre-carbonization and post-activation of a low-cost protic salt of p -phenylenediamine toluenesulfate ([pPD][2CH 3 PhSO 3 ]). [pPD][2CH 3 PhSO 3 ] is obtained by a simple neutralization reaction at room temperature and behaves as an “all-in-one” precursor, serving as C, N, S sources and a self-template. As-prepared N/S-HCSs possess large specific surface area and nanosheet geometry which provide enough adsorbing sites for charge accumulation and shorten diffusion distance of electrolyte ions at electrode/electrolyte interface. Besides, N/S-HCSs exhibit unique porous nanoarchitecture with uniform ultramicropores and a well-developed network of supermicropores and mesopores, which guarantees highly efficient ion-highways for electrolyte diffusion and transport. Furthermore, incorporated heteroatoms in the carbon framework structure improve the electrical conductivity and surface wettability, and provide extra pseudocapacitance. As a result, N/S-HCS electrode delivers superior electrochemical performance including high gravimetric capacitance (280 F g −1 at 1.0 A g −1 ), good rate performance (134F g −1 at 50 A g −1 ) and cycling stability (94.4% retention after 10,000 cycles at 2.0 A g −1 ) in 6 M KOH electrolyte. The present innovative synthetic concept can be easily implemented, without complicated procedure and particular template, and thus opens up a new window towards the simple and highly efficient synthesis of well-designed carbon-based materials for supercapacitor applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Water shortage and energy crisis become the grand challenges in the current century. • The review consolidates the recent advances of electro-AnMBRs. • Configuration, pollutant removal, fouling and bioenergy recovery are reviewed. • Perspectives on the future research needs for electro-AnMBRs are provided. • Electro-AnMBRs can serve as a nexus of wastewater treatment and bioenergy recovery. In the face of the growing water shortage and energy crisis, anerobic membrane bioreactor (AnMBR) as a promising technology of wastewater treatment and bioenergy recovery has drawn extensive attention. Recently, electrochemical processes have been integrated into AnMBR systems (electro-AnMBRs) to address the critical issue of membrane fouling in AnMBRs, as well as improve biogas recovery. In this review, we systematically summarized the recent advances of electro-AnMBRs, which would provide useful information and recommendations for the scalable application of electro-AnMBRs. The configuration of electro-AnMBRs and electrode materials are summarized in detail. Furthermore, comparisons of AnMBR performances with/without electrostimulation, including pollutants removal, membrane fouling mitigation and energy recovery, have been conducted based on the available literature. In general, electrostimulation in AnMBRs can not only enhance pollutants removal, but also lower transmembrane pressure increasing rate (10% ∼ 84.4%). Also, electro-AnMBRs operated under the same condition can increase biogas generation rate and methane yield rate, which are 60.0% and 42.1% higher than that of control, respectively. Thereafter, the challenges and future perspective of electro-AnMBR in research and applications are also discussed. This review highlights the potential and challenges that should be solved to facilitate the scalable application of electro-AnMBR in wastewater treatment and energy recovery. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe, S co-doped carbon-based catalyst is prepared using κ-carrageenan hydrogel. • Thiophene sulfur generated more active sites and promoted electron transfer to PMS. • S 2 2− accelerated the Fe2+/Fe3+ cycle and helped to generate the reactive species. • SO 4 −, OH, O 2 −, 1O 2 and FeIV were all involved in the degradation of NOR. In this study, Fe, S co-doped carbon-based catalysts (Fe@SCNs) for activation of peroxymonosulfate (PMS) were prepared by calcination of κ-carrageenan (κ-c) hydrogel cross-linked by Fe3+. The catalysts prepared at a κ-c concentration of 3 wt%, a Fe3+ concentration of 0.3 M and a calcination temperature of 900 °C showed the best performance for activation of PMS, allowing complete degradation of norfloxacin (NOR) within 40 min at a degradation rate of 0.2878 min−1. Different active species (1O 2 , OH, SO 4 −, O 2 − and FeⅣ) collaborated for the degradation of NOR, in which 1O 2 dominated the reaction. The doping of S elements in carbonaceous materials could enhance the activation capacity of PMS for the reason that S-doping facilitated the electron transfer capability of the catalysts and the introduction of thiophene sulfur (C S C) generated more active sites, while S 2 2− also enhanced the conversion of Fe3+ to Fe2+, resulting in the continuous formation of more ROS. The Fe@SCN/PMS system not only had a broad range of pH (3.0–11.0) applicability, but also was little affected by inorganic ions (NO 3 −, Cl−, HCO 3 − and H 2 PO 4 −) or organic compounds (humic acid) in water. This research provides an innovative approach for the preparation of metal and heteroatom co-doped carbon-based catalysts for sulfate radical-based advanced oxidation process. [ABSTRACT FROM AUTHOR]

[Display omitted] • PAM-conditioned sludge releases a large amount of EPS under intense shearing. • Floc breakage induces a deteriorated dewaterability for PAM-conditioned sludge. • Dewaterability of sludge conditioned by inorganic salts is less subject to shearing. • Extra shearing should be minimized for PAM-conditioned sludge in practice. • Extra shearing is not a concern for the sludge conditioning with inorganic salts. While chemical conditioning is the most commonly used conditioning process for sludge dewatering, the dewaterability of chemically conditioned sludge is found to be significantly affected by shear force. However, relevant studies are still lacked, which obstructed an in-depth understanding on sludge conditioning. In this study, we systematically investigated the impacts of floc breakage induced by shearing on the sludges conditioned with polyacrylamides (PAMs)/inorganic salts. Although PAM-conditioned sludges had better structural strength and dewaterability than the ones conditioned with inorganic salts, they exhibited a drastically deteriorated dewaterability upon floc breakage after shearing. Further analysis revealed that the PAM-conditioned flocs were mainly wrapped by polymer chains and thus floc breakage would lead to a substantial release of extracellular polymeric substance (EPS) and exposure of massive non-neutralized negative charge. In comparison, the coagulation by inorganic salts was mainly completed by charge neutralization and compression of EPS, which resulted in a conditioned sludge with a much less deteriorated dewaterability after shearing. Accordingly, PAMs are suggested as the chemical agents if screw pump is used for the sludge conditioning, while extra shearing should be minimized in the conditioning process. Inorganic salts are more applicable for the conditioning layout with a flexibly located equalization tank due to their relatively low coagulation kinetics but well-maintained sludge dewaterability. This study fills some critical knowledge gaps in the fundamental understandings on chemical conditioning process and offers a guideline for the selection of practical conditioning strategy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mechanisms and effectiveness of electrochemical and NaClO cleaning was investigated. • Electrochemical oxidation can convert BSA into foams and flocs by electrocoagulation. • Indirect electrochemical oxidation by OH· and O 2 ·- could degrade foulants. • Combination of electric field and NaClO showed great membrane cleaning efficiency. • Applying electric field before adding NaClO could efficiently inhibit the generation of HBPs. Membrane fouling can be effectively alleviated by using conductive membrane and external electric field in membrane bioreactor. However, the transformation and removal mechanism of foulants during the electrochemical process needs to be further explored. The present work investigated the degradation mechanisms and cleaning efficiency of organic foulants by electric field and sodium hypochlorite (NaClO) on the composite conductive microfiltration membranes. The results show that the electrochemical oxidation obtained a great degradation efficiency of bovine serum albumin (BSA) at current densities of 40 and 80 A/m2, which was equivalent to that of high-dose NaClO (160 mg/L). However, the degradation efficiency of sodium alginate (SA) was much lower than that of BSA under the same cleaning strategy, due to its strong antioxidant activity. It was also found that NaClO oxidation can decompose BSA macromolecules into small molecules instead of mineralization, while electrochemical oxidation can convert dissolved BSA into foams and flocs by electrocoagulation, thus reducing the BSA concentration in the solution. During the electrochemical cleaning, indirect electrochemical oxidation through the formation of strong oxidants played an important role in the degradation of BSA and SA, and the role of OH· was more significant than that of O 2 ·-. The combination of electric fields and NaClO showed great membrane cleaning efficiency. Moreover, the combination of electrochemical cleaning could not only prevent a large number of precursors from being converted to halogenated by-products, but also shorten the chlorination time and reduce the chlorine concentration, which can alleviate the secondary pollution of cleaning solution. [ABSTRACT FROM AUTHOR]

A facile encapsulation of NiO nanoparticles in mesoporous carbon nanospheres (NiO/MCNs) is demonstrated. Silicate-ion groups on nanosilica surface can react with Ni 2+ ions to generate nickel silicate in situ around the SiO 2 cores. Such hybrids are introduced into polymer nanospheres prepared by extended Stöber strategy, followed by calcination and template removal to fabricate NiO/MCNs. The typical NiO/MCNs have spherical morphology (∼280 nm in diameter), uniform mesopores (5.9 nm), high specific surface area (714 m 2 g −1 ), and well-dispersed NiO nanoparticles (7.20 wt.%). Package mesoporosity among the carbon spheres reduces ion diffusion distance, and the mesopores benefit fast ion transportation. Besides, the introduction of NiO nanoparticles not only provides pseudocapacitance, but also increases the graphitization degree of the carbons and improves crystalline structure. As a result, NiO/MCNs as supercapacitor electrodes show a high specific capacitance of 406 F g −1 at 1.0 A g −1 in 6 M KOH electrolyte, and it still maintains 315 F g −1 at a high loading current density of 20.0 A g −1 . Besides, NiO/MCN electrode retains ∼91.0% of the original capacity at 3.0 A g −1 after 10,000 cycles, exhibiting outstanding cycle stability. The easy prepared, well-structured, and high-performance NiO/MCNs provide great potential to support advanced energy storage systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrochemical ceramic membrane was fabricated by Ir sputtering deposition. • COD and TN were efficiently removed by the electrochemical ceramic membrane. • The effluent biodegradability of landfill leachate was significantly improved. • Reactive chlorine species dominated the oxidation and removal of pollutants. Efficient removal of contaminants from landfill leachate remains to be a major challenge, calling for novel technologies for advanced treatment of those high-salinity wastewaters. In this work, an iridium-decorated electrochemical ceramic membrane was fabricated via magnetron sputtering deposition for the treatment of landfill leachate. The electrochemical ceramic membrane filtration (ECMF) system achieved 70.8 ± 1.5 % of chemical oxygen demand (COD) and 31.7 ± 2.8 % of total nitrogen under hydraulic retention time (HRT) 60 min and membrane flux 50 L/(m2 h) during 14-d operation. Furthermore, the ratio of biochemical oxygen demand (BOD) to COD in the effluent was increased to 0.56 in comparison to that of the influent (0.24), indicating the increase in the biodegradability of the effluent. The reactive chlorine species generated in the system were mainly responsible for the pollutant removal in this system, efficiently oxidizing the humic substances and reducing the aromaticity of the contaminants. The energy consumption and current efficiency of the ECMF system were 49.3 kWh/ kg COD and 37.4 % at 20 mA cm−2, respectively. The results of this study highlight the potential of using the ECMF system for efficient treatment of high-salinity wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe 3 O 4 doped powdered activated charcoal was synthesized by co-precipitation. • Efficient degradation of tetracycline was achieved over a wide range of pH. • Surface-bound SO 4 •− and 1O 2 were the predominant ROS in the catalytic system. • Toxicity of the wastewater was efficiently reduced after PMS activation process. • The catalyst showed a decent recyclability and catalytic stability. Iron-mediated activation of peroxymonosulfate (PMS) has long been of a great interest for the effective oxidation of micropollutants. In this study, ferroferric oxide doped powdered activated charcoal (PAC) was prepared by a chemical co-precipitation method in which abundant ferroferric oxide nanocatalyst (FONC) were immobilized on the PAC. The catalyst (FONC@PAC) enabled an efficient degradation of tetracycline via activation of PMS over a wide range of pH and the removal efficiency could reach up to 86.9%. It was verified that the surface-bound SO 4 •− and 1O 2 were the predominant reactive oxygen species in the catalytic process. A possible degradation pathway of TC was deduced and the toxicity of treated wastewater was drastically reduced after the catalytic degradation. Meanwhile, the catalyst demonstrated a decent degradation performance even after four recycles and suffered from little iron loss. The novel catalyst demonstrated its great potential for the removal of antibiotics in the wastewater. [ABSTRACT FROM AUTHOR]

This work aims at optimizing performance of the multimode anaerobic/anoxic/aerobic (AAO) system, which could be flexibly operated under AAO, reversed AAO (RAAO) and anoxic/aerobic (AO) modes, based on effluent quality and operating costs at low temperature of 12.5 °C. Influences of sludge retention time (SRT) on effluent quality, functional biomass and operating cost were evaluated for each mode. The AAO has a better performance than RAAO and AO at SRT of 5–25 d under the same operating cost for its higher pollutant removal efficiency and concentration of phosphorus-accumulating organisms. Furthermore, an operating region conforming to required discharge standards was established for the AAO mode by regulating returned activated sludge (RAS) and mixed liquor recirculation (MLR). Optimal condition was obtained using MLR ratio of 100%, RAS ratio of 50%, and SRT of 16 d. Dynamic simulation results showed that multi-criteria modeling was a useful tool in process optimization. [ABSTRACT FROM AUTHOR]

[Display omitted] • The terephthalic acid intercalated carbon nanotube composite was developed for phosphate removal by CDI. • ZnZr-COOH/CNT electrode showed greatest phosphate adsorption capacity. • Phosphate adsorption occurred via the electrostatic attraction, inner sphere complexation and coordination exchange. • The energy consumption of CDI dephosphorization was sixteenth of that of chemical phosphate removal process. The discharge of phosphate from sewage water can lead to water eutrophication and endanger the aquatic ecosystem. Capacitive deionization (CDI) has displayed great potential for salt removal and nutrient recovery due to its excellent performance such as environmental friendliness and energy efficient. In this study, the terephthalic acid intercalated carbon nanotube composite material (ZnZr-COOH/CNT) was developed as an anode and its selective removal of phosphate in CDI was investigated. At a applied voltage of 1.2 V, ZnZr-COOH/CNT electrode exhibited great adsorption capacity of phosphate with low concentration (∼10 mg/L) at a wide range of pH (3 – 10), with the equilibrium concentration as low as 0.3 mg/L which was less than the national first-class emission standard (0.5 mg/L). Moreover, the adsorption of phosphate by ZnZr-COOH/CNT composite electrode was mildly disturbed by the coexisting ions (Cl−, NO 3 –, SO 4 2− and HCO 3 –). X-ray Photoelectron Spectroscopy (XPS) analysis indicated that the zirconium and zinc were coordinated with phosphate to form inner sphere complex, and the hydrogen bond was formed between the hydroxyl group of phosphate and the carboxyl group of electrode material, which enhanced the selective adsorption of phosphate. Furthermore, the energy consumption of CDI dephosphorization was calculated as low as 0.0075 kWh/g P and 0.043 kWh/m3 water at 1.2 V. This study was expected to provide the potential electrode materials and theoretical basis for the application of CDI dephosphorization. [ABSTRACT FROM AUTHOR]

Sulfur-oxidizing autotrophic denitrification process has drawn significant attention due to its high efficiency, elimination of carbon requirement and the effluent contamination by organic compounds. In the process, nitrate and sulfur are used as electron acceptor, and electron donor, respectively. In the present study, a novel sulfur based autotrophic denitrification process utilizing membrane bioreactor (MBR) was tested for nitrate removal from drinking water. A bench-scale MBR equipped with hydrophilic flat sheet polyethersulfone (PES) membranes (0.45 μm) was used. Sulfur was externally added to the MBR considering the theoretical requirement. Almost complete denitrification efficiency was achieved when the influent nitrate concentrations were 25–50 mg NO 3 − -N/L at HRT as low as 5 h corresponding to nitrate loading rates up to 0.24 g NO 3 − -N/(L d). The generated sulfate concentrations were close to the theoretical values. Membrane fouling was not significant at fluxes ⩽20 L/(m 2 h). [ABSTRACT FROM AUTHOR]

[Display omitted] • Nature breaks new ground in the design of antifouling membranes. • The review summarizes the recent progress of nature-inspired antifouling membranes. • Fundamentals, strategies and applications of antifouling membranes are reviewed. • Challenges and perspectives for nature-inspired antifouling membranes are provided. Membrane separation technologies have been widely used for water purification. However, membrane fouling, which arises from unwanted deposition and adhesion of foulants, significantly hinders the applications of membrane technology. In recent years, inspirations that come through materials, processes and designs of nature open a new avenue for the development of antifouling membranes. The review aims to summarize the recent progress in nature-inspired antifouling membranes. The fundamentals of membrane fouling are first discussed based on the classical theories and recent advances in available literature. Subsequently, antifouling surfaces inspired from nature, involving superwetting surfaces, antimicrobial approaches and bio-synthesis strategies, are systematically summarized and antifouling membrane fabrications based on these strategies are critically reviewed. The challenges and perspectives are also discussed to facilitate the future research and development of nature-inspired antifouling membranes. This review provides comprehensive understanding and practical guidance on the construction of nature-inspired antifouling membranes for water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel reactive electrochemical Pd-loaded porous Ti membrane was fabricated. • 96.3% SMX removal (energy cost 1.34 Wh/m3) was achieved at 0.5 mA/cm2. • Singlet oxygen (1O 2) was the main reactive oxygen species in the REM system. • 1O 2 was mainly generated on the anode via Pd–O 2 interaction. In this study, a novel reactive electrochemical membrane (REM) made of Pd-loaded porous Ti was prepared to achieve ultrafast and efficient oxidation of trace antibiotics sulfamethoxazole (SMX) under anodic polarization. At a current density of 0.5 mA/cm2, the percentage removal of SMX by the REM was 96.3% in flow-through mode, with the energy cost (i.e. , the electrical energy per order of removal, 1.34 Wh/m3) being much lower than the flow-by mode (125.76 Wh/m3) under the same operating condition. Quenching experiments and electron spin resonance spectra demonstrated that singlet oxygen (1O 2) was the main reactive oxygen species in the REM system, playing a vital role in SMX degradation. Results of this study indicated that 1O 2 was mainly generated on the anode via Pd–O 2 interaction that directly activated oxygen, rather than the evolution of 1O 2 precursors (e.g., O 2 − and H 2 O 2). The constantly high electrochemical removal of SMX (88.5–91.9%) from actual surface water demonstrated that the matrix effect on the process performance was minimal in realistic applications, highlighting this novel REM to be a viable way to remove trace organic contaminants from surface water. [ABSTRACT FROM AUTHOR]

• High charge-density polyacrylamide causes better conditioning performance. • MLiSSP reveals rapid flocs aggregation using high charge density PAM. • Flocs with a rigid and dense structure suffer less from hydraulic turbulence. • QCM-D reveals compact and rigid aggregation using high charge density PAM. While chemical conditioning has been widely used to improve the sludge dewaterability, the knowledge gap in understanding the detailed interaction between the agent and sludge as well as the structural properties of the conditioned flocs remains. In this study, we therefore investigate the mechanisms of sludge conditioning with a widely used organic flocculant, polyacrylamide (PAM), by using a suite of time-resolved characterization technologies. Compared to PAM with a low charge density, the high charge-density PAM (70%) improves the sludge flocculation and apparent filtration performance as a result of the enhanced structural strength. This is mainly attributed to the bonding between the biomolecules and PAM, resulting in the aggregation of flocs, squeezing of the water dispersed among the sludge particles and finally improvement of the dewaterability. The interaction between sludge and PAM is dynamically assessed by multiple light scattering spectroscopy and quartz crystal microbalance with dissipation. Results demonstrate that the use of high charge-density PAM quickly generates flocs with a rigid and dense structure that suffer less from the hydraulic turbulence. These findings provide mechanistic insights into the interaction between sludge and flocculant/coagulant (of different charge densities) and its impacts on the floc properties, which is beneficial to the process design and optimization for sludge conditioning, pipeline transport and dewatering in high-pressure systems. [ABSTRACT FROM AUTHOR]

• Hydrolysis tank (HAT) reduced COD for nutrient removal and inhibited nitrification. • Upgrading HAT to anaerobic side / main stream reactor (ASSR/AMSR) was studied. • Upgrading HAT improved nitrogen removal and achieved sludge reduction of 15.4–40.5%. • AMSR enriched hydrolytic and predatory bacteria, while ASSR favored slow growers. • AMSR is a cost-effective and advantageous upgrading strategy for HAT. The hydrolysis acidification tank (HAT) was usually selected as the pretreatment of combined industrial and domestic wastewater for municipal wastewater treatment plants (MWWTPs). Strict source control and urbanization substantially reduced industrial wastewater fed into MWWTPs, and thus HAT should be repurposed. Long-term survey of a full-scale MWWTP showed HAT had adverse effects on biological nutrient removal (BNR) of subsequent activated sludge systems because it increased difficulty of BNR owing to carbon source loss, and generated sulfide preferentially combining with ammonia monooxygenase in anaerobic phase of posterior biological treatment process to significantly inhibit activities of nitrifiers. Full-scale experiment of bypassing HAT achieved more efficient nitrogen and phosphorus removal, and thus three pilot-scale systems were designed to investigate process performance by upgrading HAT to anaerobic side-stream reactor (ASSR) and anaerobic main-stream reactor (AMSR). The three systems were equally effective in chemical oxygen demand (COD), total phosphorus and ammonium nitrogen removal. Upgrading HAT to ASSR and AMSR enhanced total nitrogen removal from 63.3 to 65.1 and 72.0%, and achieved sludge reduction of 15.4 and 40.5%. Intrasystem flow analysis confirmed that upgrading increased proportion of COD utilized for denitrification. MiSeq sequencing results showed that AMSR enriched hydrolytic and predatory bacteria for sludge reduction, while ASSR favored the growth of slow growers. The results confirmed that AMSR is a cost-effective and advantageous strategy for HAT upgrading with higher nitrogen removal, efficient sludge reduction, and improved sludge settleability and dewaterability. [ABSTRACT FROM AUTHOR]

• A continuous-flow photoelectrochemical filtration system was applied for Sb(III) detoxification. • Ultra-fast Sb(III) detoxification can be achieved within two seconds. • A synergistic effect between photocatalytic and electrochemical process was observed. • The Sb(III) detoxification efficiency enhanced with applied voltage. • The efficacy can be extended to similar heavy metal ions and other environmental matrixes. Herein, we designed a flow-through photoelectrochemical system consisting of a TiO 2 -nanotubes-array-mesh filter to achieve ultra-fast detoxification of highly toxic Sb(III). Upon application of UV-LED irradiation and an electrical field, in situ conversion of Sb(III) to less toxic Sb(V) can be achieved with a single-pass through the filter (τ < 2 sec). We identified an evident synergistic effect between electrochemical and photocatalytic processes. The detoxification efficiency enhanced with an increase in applied voltage from 22.6% (at 0 V) to 96.7% (at 1.5 V). This could be the combined advantages of filter's flow-through design, photoelectrochemical activity of the filter, and decreased charge recombination rate. The EPR analysis proved that hydroxyl radical dominated the process of Sb(III) conversion. At 1.5 V, 800 μg/L Sb(III)-spiked tap water still maintained an >95.6% Sb(III) oxidation efficiency. Overall, this study established a novel, effective, and promising photoelectrochemical system to accomplish the second-level detoxification of highly toxic Sb(III). [ABSTRACT FROM AUTHOR]

• A selective electrocatalytic membrane was developed using molecular imprinting. • Enhanced and preferential electrochemical degradation of 2,4-D was achieved. • Size matching and interaction of pollutant with left cavities induce selectivity. • It has great potential for selective removal of target micropollutants from waters. A selective electrocatalytic ceramic membrane filtration (ECMF) system was developed using molecular imprinting (MI) TiO 2 @SnO 2 -Sb (MI-TiO 2 @SnO 2 -Sb) anode for selectively eliminating 2,4-dichlorophenoxyacetic acid (2,4-D). The introduction of MI sites enhanced the removal of 2,4-D compared to the control. At a charging voltage of 3 V under flow-by mode, the 2,4-D removal rate of MI-TiO 2 @SnO 2 -Sb ECMF system was 1.91 times that of the control (without MI), attributed to the specific recognition sites (leading to selectivity) and the enhanced reactive oxygen species production in the presence of MI sites. In the coexistence of interferent phenoxyacetic acid herbicides, MI-TiO 2 @SnO 2 -Sb ECMF system also showed higher selective coefficient than the control (without MI). More importantly, flow-through mode could enhance the selectivity since the membrane filtration enhanced the mass transfer of target micropollutant towards MI sites. The imparted selectivity was mainly attributed to the size matching and special interaction between the target molecules and imprinted cavities. [ABSTRACT FROM AUTHOR]

• GAC-MnO 2 notably accelerates CH 4 production in anaerobic digestion. • MnO 2 acts as a catalyst to improve interspecies electron transfer. • The secretion of humic substances was inhibited by GAC-MnO 2. • Spirochaetae and Methanobacterium response to the increase of CH 4 production. The addition of conductive materials or metal oxide nanoparticles (NPs) to anaerobic systems is an attractive strategy to enhance the anaerobic digestion and the production of CH 4. This study proposed a strategy to boost the CH 4 production by adding granular activated carbon (GAC)-MnO 2 nanocomposites into an anaerobic methanogenic system. The associated mechanisms and the microbial community structure during anaerobic digestion were investigated systematically. Compared with a control with GAC only, after adding GAC-MnO 2 composite the chemical oxygen demand (COD) removal efficiency and CH 4 yield were increased by 77% and 36%, respectively. The addition of GAC-MnO 2 stimulated the secretion of extracellular polymeric substance (EPS), while the secretion of humic substances was inhibited. The spatial distribution of EPS in the anaerobic sludge affects the extracellular electron transfer efficiency as well. Manganese ions concentrated in the EPS layer facilitated the electron flow and, thus, accelerated the extracellular electron transfer. The enhancement of anaerobic methanogenesis can be mainly attributed to the reduction/oxidation cycle of Mn4+/Mn2+. Electron transfer system activity and Cytochrome C content reached up to 341 and 38 nmol/L, respectively, under optimal conditions. 16S rRNA gene sequencing analysis indicated that Spirochaetaceae, Cloacibacterium , and Treponema were the dominant bacteria. The abundance of the methanogenic archaea Methanobacterium and Methanosaeta were increased with the addition of GAC-MnO 2. [ABSTRACT FROM AUTHOR]