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• OFGs, PFRs and redox properties of BC facilitate the generation of ROS. • BC and BC-based catalysts could effectively activate H 2 O 2 and persulfate. • BC-based photocatalysts could effectively degrade pollutants. • BC-based catalysts could effectively degrade pollutants in sonocatalytic systems. • BC-based catalysts may be a good alternative for the degradation of pollutants. Biochar (BC) is one of the most remarkable materials for environmental remediation. An increasing number of researchers have attempted to utilize BC as a catalyst to generate reactive oxygen species (ROS) and sulfate radicals. This work focuses on the development and progress of BC-based catalysts in different systems, including redox systems, Fenton-like systems, sonocatalytic systems and photocatalytic systems. Most importantly, the catalytic performance and mechanism of different types of BC-based catalysts are thoroughly investigated. Furthermore, the applications of BC-based catalysts in wastewater, sediments, soil and gas are presented. Special attention is paid to the factors involved in the generation of ROS and sulfate radicals, such as oxygen-containing functional groups (OFGs), persistent free radicals (PFRs) and redox properties. The generation processes of ROS and sulfate radicals are presented in detail. And the removal pathways of three mechanisms are elaborated. Furthermore, research in this field is still at an early stage, and many improvements are required before the technology can be efficiently scaled up and put into practice. This review enriches the knowledge about the generation processes of ROS and sulfate radicals by BC-based catalysts and improves the understanding of the catalytic performance and catalytic mechanism of BC-based catalysts for pollutants. [ABSTRACT FROM AUTHOR]

• The dynamic equilibrium of active hydrogen plays an important role in the reduction process of nitrate to ammonia production. • The electrocatalytic activity of cobalt-based catalysts is greatly improved by phosphidation process. • A series of cobalt phosphide nanowire array catalysts with different phosphidation degrees are constructed. • The optimal CoP NWAs/NF-300 catalyst shows super NRA performance. Electrocatalytic nitrate reduction to ammonia (NRA) is a promising strategy for restoring the global nitrogen cycle imbalance while opening up a sustainable avenue for ammonia synthesis. However, the ammonia selectivity and Faradaic efficiency (FE) of electrocatalysts are restrained by the multiple complex reactions during the whole electrolysis process. Herein, we synthesized a series of cobalt phosphide nanowire array catalysts with different phosphidation degrees grown on nickel foam (CoP NWAs/NF). An extremely high nitrate conversion rate of 97.9% as well as ammonia selectivity and FE of ∼ 100% were attained by the optimal CoP NWAs/NF-300 in the NRA reaction, which was much superior to those of counterpart Co 3 O 4 NWAs/NF catalyst and reported cobalt-based catalysts. Several control experiments and density functional theory calculations together unveil the dynamic equilibrium of active hydrogen production and consumption, which is conducive to simultaneously obtaining the super selectivity and FE for ammonia synthesis. This work provides a novel insight for the rational design of high-performance NRA electrocatalyst. [ABSTRACT FROM AUTHOR]

Defect WO 3 -carbon hybrid nanosheets (D-WO 3 @C), synthesized by a facile hydrothermal method, is utilized as an effective visible-light driven photocatalyst for sustainable inactivation of bacteria . Detailed characterization through SEM-EDS, XRD, FT-IR, HRTEM, and XPS confirmed the formation of the nanohybrids. As a result, the as-synthesized D-WO 3 @C exhibited the best sterilization efficiency among all of the WO 3 photocatalysts, and 7 log inactivation of E. coli or S. aureus was obtained after treating samples for 45 min with 1000 μg/mL D-WO 3 @C. It was found that D-WO 3 @C exhibited enhanced visible-light-driven photocatalytic sterilization in killing bacteria compared with D-WO 3 and P-WO 3 . The results show that the oxygen vacancies and carbon matrix were able to promote photocatalytic performance by triggering a faster interfacial transfer and a higher efficient separation of electron-hole pairs, which most likely is the reason behind the improved bactericidal effect. Furthermore, fluorescent-based cell viability/death tests and SEM technology were employed to demonstrate the lethal effect as well as the integrity of bacterial membranes during photocatalytic process. Photoelectrochemical techniques and UV–visible diffuse reflectance revealed the efficient separation of electron-hole pairs between D-WO 3 and carbon matrix. More importantly, after being tested in four cycles, D-WO 3 @C showed good photocatalytic performance due to its chemical stability. The excellent properties associated with the novel D-WO 3 /C indicated that they could be considered as a promising light-visible driven photocatalyst to remove, in practice, microbial contamination of water. [ABSTRACT FROM AUTHOR]

[Display omitted] • The sterilization efficiency of hybrid nanoflowers can reach 100% under 30 min light treatment. • Adjusting the structure and bandgap to improve the sterilization performance of the materials. • Adhering first and then generating ∙OH lead to bacterial damage and ultimately inactivation. Organic-inorganic hybrid nanoflowers have made exciting achievements in the field of catalysis due to their unique morphology and structural characteristics. Nevertheless, their photocatalytic sterilization effects have not been fully explored. In this study, bovine serum albumin (BSA) were used as "glue" and induced the formation of three nanoflowers. Experimental results show that under simulated visible light, nanoflowers can reach 100% bacteria inactivation within 30 min. Mechanistic studies indicate that adjusting the band gap can effectively improve the light absorption properties of photocatalytic materials. More importantly, the increase of BSA content in the material will cause the improvement of hydrophilicity, which greatly facilitates the adhesion of microorganisms to kill bacteria. In addition, the in vivo experimental results showed that the material has a significant effect on bacterial wound healing. This work provides guidance for improving the photocatalytic sterilization performance of antibacterial agents by adjusting the size and structure of the materials. [ABSTRACT FROM AUTHOR]

We report a simple in situ technique to deposit nanoparticles of copper oxide on the cellulose paper which forms a stable layer of CuO. This method can be used to deposit copper oxide on any substrate provided that it is wettable and tolerates relatively high pH around 10–12 for several hours. Same method was applied to deposit CuO on commercial textile and polyethersulfone flat sheet. The resultant CuOpaper shows superior antibacterial activity against Gram-positive and Gram-negative bacteria. This antibacterial effect is due to release of copper ions from CuO nanoparticles on the paper. The resultant composite can be used as cheap point of use system to produce safe, pathogen free drinking water. [ABSTRACT FROM AUTHOR]

Highlights: [•] Silver nanoparticles were deposited on MWNTs by chemical deposition method. [•] Ag/MWNTs were coated on the surface of UF PAN hollow fiber by physical method. [•] The antibacterial properties of the coating were tested in continues mode. [•] The coating is regenerable after silver depletion. [ABSTRACT FROM AUTHOR]

Abstract: Part I of this study presents a theoretical method combined with experiments to determine the adsorption kinetics of powdered activated carbon (PAC) in the hybrid PAC-submerged membrane (SM) system with air bubbling for trace organics removal. The homogeneous surface diffusion model (HSDM) was applied to describe the kinetics of the adsorbate uptake. The differences between the model solutions and the corresponding experimental results were minimized by means of Levenberg–Marquardt algorithm so that two kinetic parameters D S and k f involved in HSDM were obtained simultaneously. The D S was found to be 1.14×10−16 m2/s and the k f value was correlated with the bubbling rate (Q b ) and carbon dosage (C c ), which are required in the modeling of the hybrid PAC-SM system presented in Part II of this study. The k f was enhanced from 1.18×10−4 to 4.18×10−4 m/s when the bubbling intensity increased in the intermittent bubbling tests, suggesting that from energy consumption point of view, the high intensity intermittent bubbling is more efficient in improving the liquid film mass transfer than continuous bubbling with the same net bubbling rate. [Copyright &y& Elsevier]

Abstract: The hybrid powdered activated carbon (PAC)-submerged microfiltration hollow fiber membrane system with air bubbling has been simulated at two operation strategies of batch and continuous PAC dosing for trace organics removal from water. The mathematical models were developed based on corresponding solute mass balance equations and the homogeneous surface diffusion model (HSDM), where the two kinetic parameters D s and k f were obtained in Part I of this study. After verification with experiments using atrazine as the model trace organic compound, the developed models were used to predict the product water quality at various operating conditions. It was found that at the batch PAC dosing mode, the trace organic removal can be improved by increasing the bubbling rate or increasing the operation flux. While at the continuous PAC dosing mode, the target compound removal is independent on the bubbling rate, which suggested the possibility of reducing energy consumption by inducing a low bubbling rate. Besides, lower operation flux shows more benefit because of the longer hydraulic retention time. The simulation can provide a better understanding of the system and assist in evaluating various operation strategies properly. [Copyright &y& Elsevier]

Abstract: In the towns and countryside in the west of China, potato starch wastewater is an important source of water pollution as it is organic wastewater which is produced in high concentrations. The anaerobic–aerobic integrative baffled bioreactor is a new type of mobile equipment which is effective in the treatment of potato starch wastewater. In order to increase the efficiency of the anaerobic–aerobic integrative baffled bioreactor, porous burnt-coke particles, a waste product of heavy industry, were used as carriers in the aerobic pond to support the growth of microorganisms. Using this technique, the maximum reduction in chemical oxygen demand (COD) achieved was 98.7%, and the COD value in the effluent was less than 200mg/L under the following operational conditions: pH 5.0–8.5 at 25–35°C. The ammonium nitrogen (NH3–N) concentration in the wastewater was 10mg/L and the use of burnt-coke removed 82.3% of this contaminant. [Copyright &y& Elsevier]

Abstract: A set of batch adsorption kinetic tests of atrazine adsorption by powdered activated carbon (PAC) was performed using air bubbling as the mixing method. It was found that air bubbling at appropriate rates could achieve good mixing. Even a slight turbulence generated by a few bubbles could provide a reasonable mixing to facilitate PAC adsorption compared with unstirred processes. The estimated mass transfer coefficient in the liquid film surrounding the PAC particles increased linearly with the increase in air bubbling rate up to a plateau value. The experimental mass transfer coefficients in the bubbling system compared favorably with values calculated using correlations developed for conventional magnetic stirring systems, with the help of a conversion of the bubbling rates to the equivalent stirring speeds. The effect of intermittent air bubbling on the adsorption rate was also tested by generating bubbles intermittently at different net air flow rates. It was found that at the same net flow rate, intermittent higher intensity sparging could be more efficient for the PAC adsorption than continuous lower intensity sparging. This suggests that intermittent high intensity bubbling is the preferable operation, with the potential not only to assure good PAC adsorption efficiency but also to reduce the air/energy consumption. [Copyright &y& Elsevier]

[Display omitted] • RO-type polyamide (PA) thin-film was synthesized on ceramic tubular substrates. • The PA-ceramic membranes showed excellent performance and stability in HT-RO. • The MWCO increased at HT and surface charge was critical for salt rejection. • PA thin-films are stable at < 75 °C but thermal hydrolysis was observed at 80 °C. • The robustness of the substrates could enhance the membrane stability in HT-RO. Polyamide thin-film composite (TFC) membranes are widely used for reverse osmosis (RO), but most commercial RO membranes have a limited operating temperature of <45 °C. This has constrained the broader applications of RO in industries, where process and water feeds with high temperature >50 °C are common. In this study, robust polyamide-ceramic TFC membranes were developed for high-temperature RO (HT-RO). RO-type polyamide thin-film was successfully synthesized on the inner surface of ceramic tubular membranes via interfacial polymerization. The polyamide-ceramic membranes exhibited excellent thermal stability, maintaining high NaCl rejection (>98 %) and steady water permeability (∼5 LMH/bar) during HT-RO at 70 °C. The molecular weight cut-off (MWCO) of the membranes increased slightly from 90 to 140 Da at 70 °C, and the surface charge played an important role in maintaining the high salt rejection. Long-term stability tests showed that polyamide thin-films may undergo thermal hydrolysis at 80 °C. It was also found that polymeric substrates of flat-sheet RO membranes may experience serious compaction at high temperature, which could subsequently affect the performance and stability of the polyamide layer. The ceramic substrates provide strong support at high temperature, and the highly stable polyamide-ceramic membranes demonstrated huge potential for RO applications under more challenging conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The novel AgVO 3 /BiO 2-X catalyst can be cheaply and easily fabricated. • AgVO 3 /BiO 2-X is an efficient full solar spectrum photocatalyst. • DFT calculations reveals the mechanism of improved photocatalytic disinfection. • Biocompatibility experiments showed that our composites are safe materials. Photocatalytic disinfection has been regarded as a promising strategy in terms of significantly reducing microbial contamination, in which the activity of photocatalyst mainly depends on UV or visible light, however the effect of full spectrum solar light for photocatalytic disinfection has been rarely considered. Herein, we report a UV-Visible-NIR responsive photocatalyst based on vanadate quantum dots (AgVO 3 QDs) interspersed on vacancy-rich BiO 2-X (AgVO 3 /BiO 2-X) and achieve highly efficient photocatalytic disinfection for Methicillin-resistant Staphylococcus aureus (MRSA). With our approach, we achieved a 7-log inactivation of bacterial concentration within 30 min, with only a small amount of material (200 μg mL−1) under UV, visible and near-infrared light. The maximum absorption edge of AgVO 3 /BiO 2-X red-shifts from 880 nm to 930 nm, which can be attributed to the inner defective structure and formation of heterostructures, resulting in abundant production of reactive oxygen species (ROS) for bacterial inactivation. DFT calculations confirm the intimate interface contact between BiO 2-X and AgVO 3 , which benefit to the up-conversion photoluminescence properties of AgVO 3 QDs and fast interfacial electron transport through the electron tunneling mechanism. In vitro results illustrated that ROS can severely damage the cell wall of bacteria and inhibit its virulence factors, which eventually leading to the death of MRSA. Notably, assessment of wound infection showed that the material was very effective for promoting cell proliferation and differentiation, by phosphorylation of protein kinase B (Akt) signalling pathway in bacterial infection, which shows great potential as a safe, low-cost and efficient multimodal heterostructured photocatalyst in eliminating the microbial contaminated water. [ABSTRACT FROM AUTHOR]

• Recent advances of photodynamic inactivation are overviewed. • Various enhanced photodynamic inactivation strategies are articulated. • The various targeted inactivation organisms are given. • The corresponding efficacy and mechanisms of sterilization are also summarized. • Challenges and directions are discussed. Photodynamic inactivation that can directly utilize renewable solar energy for sterilization has attracted widespread attention in countering global environment deterioration and bacterial pollution. Graphitic carbon nitride (g-C 3 N 4), a metal-free polymeric semiconductor with a mild band gap (2.7 eV), excellent optical properties and physicochemical stability, has become a hot-spot in photocatalytic sterilization. Nanostructured materials have shown great potential in improving the photodynamic inactivation efficacy of bulk g-C 3 N 4. This review systematically analysed and summarized the latest studies on g-C 3 N 4 based nanostructured materials for photodynamic inactivation. First, strategies to enhance the sterilization of g-C 3 N 4 -based nanostructured photodynamic inactivation materials and their contemporary challenges are briefly introduced. Second, the light source and synthetic methods are described. Third, the targeted inactivation organisms, including Gram-negative bacteria, Gram-positive bacteria, drug-resistant bacteria, harmful algae and bacteriophage, are described. In addition, the photocatalyst concentration, corresponding efficacy and mechanisms of sterilization are discussed. Finally, the deficiency and possible future perspectives of g-C 3 N 4 -based nanostructured photodynamic inactivation materials are articulated. [ABSTRACT FROM AUTHOR]

In this study, a novel CoFe 2 O 4 nanocatalyst impregnated Al 2 O 3 ceramic membrane was prepared via a urea-assisted one-step combustion method. The catalytic membrane was characterized by field emission scanning electron microscopy (FESEM) with energy dispersive X-Ray analysis (EDX) and applied for the catalytic degradation of sulfamethoxazole (SMX) via peroxymonosulfate (PMS) activation under a dead-end membrane filtration mode for the first time. Results indicate that CoFe 2 O 4 could be impregnated into the macropores throughout the whole Al 2 O 3 ceramic membrane via this method and the CoFe 2 O 4 loading amount could be controlled by the multiple impregnation cycles. The membrane filtration operation mode significantly enhances the accessibility of the catalytic active sites to PMS and SMX in microreactor environment and thus the CoFe 2 O 4 impregnated membrane displays excellent catalytic activity for the SMX degradation. The pure water permeability flux can maintain at ∼3000 L m −2  h −1  bar −1 (LMHB) with the catalyst loading amount of 0.015 g/g Al 2 O 3 . In the membrane filtration system, the removal rate of SMX with the initial concentration of 10 mg L −1 can achieve to ∼98%, 70% and 40% with the residence time of 90, 36 and 18 s. The catalytic membrane shows a great tolerance at wide pH range (3–11), the existence of humic acid and anions. Meanwhile, the membrane shows self-cleaning property by retaining >90% of initial flux after 3 treatment cycles. Electron paramagnetic resonance (EPR) and radical quenching experiments indicate that both sulfate radical and hydroxyl radical are generated and sulfate radical is the dominant active species in the process. [ABSTRACT FROM AUTHOR]

[Display omitted] • The immobilization of FeWO 4 nanoparticles offered a new heterogenous Fenton catalyst. • Immobilized FeWO 4 catalyst was capable of activating H 2 O 2 with high stability. • The HF and HEF processes presented an effective tetracycline degradation. • The HEF process greatly reduced the pollutants in crude oil tank cleaning wastewater. • Mechanism of pollutants removal in the developed HEF process was proposed. The immobilization of FeWO 4 nanoparticles was carried out utilizing polytetrafluoroethylene (PTFE) as adhesion agent and Na 2 SO 4 as pore-forming agent, to develop a novel heterogenous electro-Fenton (HEF) process for the degradation of organic pollutants in neutral medium. The immobilized ferrous tungstate (FeWO 4) catalyst exhibited a certain catalytic activity towards hydrogen peroxide (H 2 O 2) activation generating active species (OH, O 2 – and 1O 2), by which an effective tetracycline degradation was achieved under neutral condition. The low Fe-leaching amount indicated that the immobilized FeWO 4 catalyst owns high chemical stability. Based on the above results, the HEF process was developed with one super-hydrophobic carbon cathode, one titanium-based oxide anode and the immobilized FeWO 4 catalyst, which exhibited favorable ability for the degradation of organic pollutants attributed to the combined action of electro-Fenton oxidation and anodic oxidation. Under the optimum conditions, for the degradation of 40 mg L–1 tetracycline, the HEF process presented 100% tetracycline removal within 60 min. Furthermore, the treatment of crude oil tank cleaning wastewater by this oxidation process for 8 h presented the chemical oxygen demand (COD) removal of 85.0% and the total organic carbon (TOC) removal of 75.2%, whereas the other typical pollutants: ammonia nitrogen (NH 4 +-N) and volatile phenols were removed completely. After the treatment, the oil tank cleaning wastewater can be used as the recycled water or discharged into some surface waters directly. This work shows that the HEF process characterized by easy catalyst separation can not only effectively degrade organic pollutants but avoid the production of iron sludge and the inconvenience of pH adjustment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The nature and classification of silver-containing wastewater is summarized and analyzed; • Various treatment methods for silver-containing wastewater are comprehensively described and compared; • The future direction of silver containing wastewater treatment technology is proposed. Due to its exceptional physicochemical characteristics of silver, silver is widely used in various industrial applications such as photography, minting, electroplating, and metal alloys. As a result, a significant amount of wastewater containing silver is generated. It would cause serious harm to both humans and the natural environment if left untreated, leading to the wastage of precious silver resources in the process. Therefore, this study provides a detailed introduction to the types, characteristics, and hazards of silver-containing wastewater. Furthermore, this study offers a comprehensive overview of the research advancements in treating silver-containing wastewater through various methods including chemical precipitation, electrochemical method, adsorption, ion exchange, membrane filtration, photocatalytic method, and integrated techniques. Based on this foundation, the removal effects and mechanisms of various treatment methods are thoroughly discussed in conjunction with experimental studies and characterization tests. Furthermore, this study conducts a comparison of the advantages, disadvantages and scope of application of various treatment methods. Additionally, it anticipates the future development of silver-containing wastewater treatment technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • "Edge in-situ heterogeneous" BiOI was synthesized. • BB exhibited the structures of both iodine defects and in-situ bismuth deposition. • The visible-light utilization and charge separation efficiency of BiOI were enhanced. • BB displayed excellent bactericidal ability and wound healing performance. The inherent narrow band gap of bismuth oxyiodide (BiOI) consistently leads to the rapid recombination of photogenerated carriers, significantly constraining its practical utility. To combat this shortcoming, we devise a Bi/BiOI 1−x (BB) nanosheet with edge heterostructure. It is modified by the introduction of both iodine defects and in-situ bismuth deposition through high-temperature calcination and solvothermal strategy. Notably, the in-situ deposition of bismuth enhances the visible-light absorption ability of BiOI. And the incorporation of iodine defects initiates a modification in the band position of BiOI, ultimately diminishing the electron-hole recombination rate effectively. More importantly, facilitated by the major work function of bismuth, a Schottky barrier is formed at the BB heterojunction interface, which effectively promotes the separation of photogenerated charges within BB. And the photocurrent intensity of BB is 4 times higher than that of pure BiOI. These ingenious designs result in a significant boost in the generation of reactive oxygen species (ROS) through the accumulation of electrons and holes on the surfaces of both Bi and BiOI 1−x. And BB photocatalyst shows an outstanding broad-spectrum bactericidal performance. The antibacterial rates against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) are 88.01% and 90.01%, respectively, which are increased by 80.6% and 83.8% compared with BiOI. Moreover, in vivo experiments provide compelling evidence for the BB photocatalyst's potential in promoting wound healing. The healing rate after BB treatment has already reached more than 95% on the fifth day. This work offers valuable insights on enhancing the sterilization performance of photocatalysts based on the synergistic effects of defect engineering and non-noble metal deposition. [ABSTRACT FROM AUTHOR]

• Ultrafine FeCuAgCeGd–based high–entropy nanozyme (HEAzyme) was developed. • FeCuAgCeGd–based HEAzyme exhibits high POD–like activity. • The POD–like activity mechanism of FeCuAgCeGd–based HEAzyme was proposed. • FeCuAgCeGd–based HEAzyme was used as sensor for dopamine on-site detection. Point–of–care testing (POCT) plays vital role in clinic field, especially in resource–limited areas. The nanozyme–based colorimetric platform is the potential strategy for POCT. Therefore, a high–entropy allay nanozyme (HEAzyme) was prepared via formaldehyde–assisted metal–ligand crosslinking method using multi–metal (FeCuAgCeGd) species. The obtained FeCuAgCeGd–HEAzyme showed coordination nanoparticles with ultrafine size (average size was approximately 5 nm). The peroxidase–like (POD–like) activity of FeCuAgCeGd–HEAzyme was verified through density functional theory (DFT) calculations, demonstrating the capability of FeCuAgCeGd–HEAzyme to catalyze H 2 O 2 and generate hydroxyl radicals (•OH). These radicals can oxidize colorless 3,3′,5,5′–tetramethylbenzidine (TMB) to blue oxTMB. Dopamine (DA) scavenges •OH, resulting in an "on–off" effect for TMB oxidation. Subsequently, an FeCuAgCeGd–HEAzyme colorimetric sensor was developed for DA detection, which features a low detection limit of 0.77 µM and a linear range of 5.0–70.0 µM. The sensor demonstrated a recovery ratio in spiked serum samples ranging from 97.7 % to 104.3 % with high stability and favorable selectivity. Furthermore, an FeCuAgCeGd–HEAzyme POCT platform was designed for on–site detection of DA, achieving a reliable linear detection range (5.0–70.0 µM) and a low detection limit (5.69 µM). This platform offers a facile and efficient strategy for rapid, visual, and on–site DA detection in clinical settings with advantages of cost–effectiveness and ease of operation. [ABSTRACT FROM AUTHOR]

• Ab-oriented amorphous Zn-based nanocomposites are produced for nanolabels. • A powerful CAbD strategy is raised by innovatively integrating three elements. • A mLFIA mediated by CAbD strategy was constructed for monitoring of SEMI and AOZ. • The CAbD strategy can be a universal and scatheless mAb 1 orientation approach. • The CAbD strategy reduces mAb 1 consumption and enhances the sensitivity of mLFIA. The quantity and orientation of antibodies are key elements affecting the bioactivity of immunoprobes, which have important influences on the sensitivity and specificity of immuno-biosensors. In this work, a multiplex lateral flow immunoassay (mLFIA) mediated by a powerful cascaded antibody directionality (CAbD) strategy was constructed for the simultaneous monitoring of nitrofurazone and furazolidone metabolites in food samples. Here the CAbD strategy innovatively integrated three elements: antibody staining by Coomassie brilliant blue R-250, directional anchoring of second antibodies (Ab 2) by the amorphous ZnO-based nanocomposites (ZnO-CBB-Ab 2 , ZnO-NCMs), and orientation of detection antibodies (mAb 1) by the Ab 2. The ZnO-NCMs play a double role in antibody orientation and signaling to exhibit. Thanks to the difference in surface electrical properties of Fc and Fab segments in immunoglobulin G, the excessive R-250 stained Ab 2 was anchored in ZnO-NCMs to form a multi-detection signal tag with colorimetric signal brightness. Compared with immobilization strategies of directly directional anchor-hold or post-adsorption of mAb 1 , this strategy can reduce the mAb 1 consumption, better ensure the activity and utilization efficiency of mAb 1 , and shorten the construction time of the mLFIA system. As expected, the mLFIA is given satisfactory performances with a calculated sensitivity of 0.106 and 0.060 ng mL−1 for nitrofurazone and furazolidone metabolites, respectively. The developed multiplex immunosensor ultimately shows its application potential for point-of-care testing by performing well in fish and honey samples with accredited recoveries. It's worth emphasizing that the CAbD strategy can be a universal and scatheless antibody-directed approach, especially in multiplex immunoassays for ultrasensitive food safety monitoring. [ABSTRACT FROM AUTHOR]

The superior performance of Pd/YS-TiN nanoreactor in electrocatalytic hydrodechlorination is attributed to the synergistic mechanism between strong metal-support interactions and enhanced mass transfer during the reaction enrichment process. [Display omitted] • Pd-loaded yolk-shell structured TiN spheres (Pd/YS-TiN) are designed as nanoreactor. • Pd/YS-TiN nanoreactor affords high efficiency and durability in EHDC of 2,4-DCP. • Pd/YS-TiN affords higher dechlorination degree and current density than single Pd. • Pd/YS-TiN boosts the 2,4-DCP enrichment by mass diffusion around Pd surface. • Electron-enriched Pd weak the product adsorption by strong metal-support interactions. Enhancing the enrichment behavior of low-concentration chlorinated organic pollutants remains a significant challenge in electrocatalytic hydrodechlorination (EHDC) technology. Metal-loaded hollow nanoarchitecture has emerged as a promising nanoreactor to improve reaction enrichment behavior because of its tailorable microenvironments and electronic properties. Herein, a structural engineering strategy is developed to synthesize yolk-shell structured TiN spheres supported Pd nanoreactors (Pd/YS-TiN) with confined mesoscopic spaces. Characterization by multiple techniques reveals that the yolk-shell structure of YS-TiN, with high specific surface area (139.0 m2/g) and appropriately mesoporosity (6.9 nm), exposes numerous Pd nanoparticles (∼4.0 nm) on outer/inner surface of the shell and yolk-core solid sphere, ensuring an efficient utilization of active sites for enhancing the 2,4-DCP detoxification. Consequently, the structurally optimized Pd/YS-TiN nanoreactor consistently displays maximum reaction kinetics, dechlorination degree, faradaic current density, H* utilization and product selectivity, surpassing hollow TiN-supported Pd and Pd/C catalysts. The super EHDC performance of 91.8 % 2,4-DCP conversion, a specific activity of 1.68 min−1 mol Pd −1, and a mass activity of 6.06 min−1 g Pd −1 is obtained at −0.85 V and 180 min, outperforming most reported catalysts. Combining experimental and density functional theory results, the exceptional reaction enrichment behavior of Pd/YS-TiN originates from (1) alleviating the overstrong adsorption of product phenol through strong metal-support interactions and (2) enhancing mass transport efficiency facilitated by the local concentration gradient and mesoporous shell. This study elucidates how metal-support interactions and mass transport synergistically enhance reaction enrichment behavior, showcasing potential benefits in environmental remediation applications. [ABSTRACT FROM AUTHOR]

• A binary composite MoS 2 /TiO 2 NTAs was synthesized for photocatalytic sterilization. • The water disinfection efficiency of MoS 2 /TiO 2 NTAs was up to 98.5%. • The water disinfection efficiency still reached 92.1% after 3 times recycling. • The mechanism is the damage of bacterial by O 2 – produced by photoexcitation. Despite the development of advanced photocatalysts, the practical application of photocatalytic water disinfection is still under restrictions due to the low reusability of powder photocatalysts. In this paper, we synthesized the binary composite heterojunction photocatalyst MoS 2 /TiO 2 nanotube arrays (MoS 2 /TiO 2 NTAs), using anodic oxidation method and hydrothermal method. The water disinfection efficiency of MoS 2 /TiO 2 NTAs under visible light irradiation against pathogenic bacteria was up to 98.5% and still reached 92.1% after 3 times recovering and recycling. The mechanism was proven to be the seriously damage of bacterial cell membrane caused by the ROS produced from MoS 2 /TiO 2 NTAs photocatalyst under light irradiation. In addition, we analyzed the water sample changes after material recovery by ICP-MS, and found that there is no MoS 2 nanosheet falling off. This result supported the recyclable effect of MoS 2 /TiO 2 NTAs and avoided the nanoparticles remaining in the water as much as possible. Therefore, MoS 2 /TiO 2 NTAs composites have great application prospects in water disinfection due to their excellent photocatalytic disinfection effect, recyclability and reusability. [ABSTRACT FROM AUTHOR]

• 71% OH was allocated to dedicatedly remove oil rather than SOM with inactive SOM-Fe. • Efficiently dedicated oxidation of long-chain crude oil with inactive SOM-Fe. • Inactive SOM and inactive functional group cannot consume considerable OH. To find out the mechanism of efficiently dedicated oxidation of long-chain crude oil in the Fenton system with inactive SOM-Fe, two crude oil-contaminated soils with different concentrations (S1: 14579 mg/kg; S2: 15491 mg/kg) were used as the treatment targets in this study. The results showed that the removal of long-chain crude oil (C 21 –C 30) with inactive SOM-Fe (3120–6930 mg/kg) was much higher than that with active SOM-Fe (2493–4424 mg/kg). Moreover, about 62%–71% OH was allocated for direct oxidation of long-chain crude oil with inactive SOM-Fe compared to that with active SOM-Fe. Meanwhile, the highest removal of long-chain crude oil by unit OH yield was 1345 mg/kg for inactive SOM-Fe, which was 3.6 times that for active SOM-Fe. It can be seen that less OH were consumed by organic matter and more OH was allocated to dedicatedly oxidize long-chain crude oil in inactive SOM-Fe Fenton system. Further analysis found that, for inactive SOM-Fe the low content of active organic matter (protein Ⅰ and protein II) and the active organic functional group (C O), while high content of inactive organic matter (fulvic acid, microorganism and humic acid) and inactive organic functional groups (C H and O H) was observed. Therefore, the allocation of OH was changed after SOM was inactivate, which result in less consumption of OH by SOM and efficiently dedicated oxidation of long-chain crude oil in the soil by inactive SOM-Fe. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pd/Al 2 O 3 produced less N 2 O and NH 3 than the Pd/ZrO 2 under fuel-rich cycle. • The N 2 O generation is related to the activity of nitrates after NO x adsorption. • The NH 3 is originated from the reaction of nitrates with surface hydroxyls or steam. • ZrO 2 rather than Al 2 O 3 acts as an electron acceptor from Pd for NO adsorption. Reducible and nonreducible supports usually display distinct properties on the size, valence, and coordination of Platinum group elements in supported metal oxide. However, there are few reports on the regulation of main and side reaction rates and inhibition of byproducts from the perspective of reaction kinetics. Here, we compare the N 2 O and NH 3 formations of Pd supported on Al 2 O 3 and ZrO 2 in NO reductions. Pd/Al 2 O 3 produces less N 2 O and NH 3 in quantity than Pd/ZrO 2 , which could be due to the moderate metal-support interactions between Pd with higher average valence and Al 2 O 3 with lower ability of electrons transfer. ZrO 2 acted as an electron acceptor in NO reduction facilitating the formations of unstable nitrates and surface hydroxyls. In-situ DRIFTS and NAP-XPS results suggest that the N 2 O generation is directly related to nitrates with different stabilities: bridging, bidentate, and partial monodentate nitrates are active on Pd/ZrO 2 , whereas, only nitro and partial bridging nitrates are active on Pd/Al 2 O 3. The NH 3 is mainly originated from the reaction of nitrates to surface hydroxyls with different coordination numbers. This work clarifies the byproducts formation mechanism in NO reduction and opens up the research topics using in-situ spectroscopy methodology. [ABSTRACT FROM AUTHOR]

• Functionalized PAN-Co-C membranes were developed via one-step PAN carbonization. • Co works as a dual-functional catalyst in tuning carbon formation and PMS activation. • All functionalized membranes could activate PMS to generate sulfate radicals. • High permeability was attributed to the formation of graphite carbon and cobalt. • The membrane showed excellent antifouling property with high HA removal. A novel polyacrylonitrile (PAN)-induced carbon membrane with in-situ encapsulated cobalt crystal was developed via a one-step carbonization method and applied for peroxymonosulfate (PMS) activation. The dual-function of cobalt in tuning carbon formation and activating PMS was explored. The growth mechanism of the functionalized membrane was investigated via TGA-DSC, FTIR, XRD, Raman and XPS. Results indicated that the addition of cobalt could tune the formation of C and N containing functional groups in the carbon membrane. The membrane morphologies and surface properties were further characterized by FESEM and AFM. Batch studies revealed that more than 90% of sulfamethoxazole (SMX) could be degraded after 60 min of membranes exposure in the presence of PMS. Electron paramagnetic resonance (EPR) results verified the generation of sulfate radical in this process. The removal of humic acid (HA) in a dead-end membrane filtration mode could be maintained at ∼100% with an inconspicuous sacrifice of permeate flux over 450 min. The permeate flux achieved with PMS was higher as compared to the case without PMS addition, which could be ascribed to the catalytic oxidation of organic molecules accumulated on the membrane surface. The catalytic property imports an intrinsic antifouling property of the carbon membrane in the hybrid catalytic membrane filtration process. [ABSTRACT FROM AUTHOR]

A novel Co 3 O 4 nanocatalyst functionalized Al 2 O 3 ceramic membrane (CoFCM) with a honeycomb structure was prepared via an optimized surface-nucleated zeolitic imidazolate framework (ZIF-67) growth method. The Co 3 O 4 hollow structure which was confirmed via chemical characterizations (XRD, FTIR, Raman and XPS), was formed on the membrane surface by one-step calcination of ZIF-67 membrane. The CoFCM was characterized by various techniques including the field emission scanning electron microscopy and atomic force microscopy. The results revealed the formation of well-defined Co 3 O 4 layer on the porous Al 2 O 3 ceramic membrane with the thickness of 1.5–2 µm. The growth mechanism of CoFCM was further proposed via XPS and the catalytic activity of CoFCM was investigated for the removal of sulfamethoxazole (SMX) with the addition of Oxone. The membrane performance was examined under a home-made dead-end mode. Results indicated that CoFCM has a rougher surface with an initial membrane resistance of 1.19 × 10 11  m −1 and performs outstanding catalytic activity. The pure water permeability of CoFCM is 3024 L m −2  h −1  bar −1 , which is comparable to that of the pristine ceramic membrane (<10% difference). The SMX removal efficiency achieved to >90% in 90 min with an Oxone addition of 0.1 g L −1 . Meanwhile, the membrane showed excellent durability by retaining >95% of initial flux for at least 3 operational cycles with a low cobalt ion leaching via Oxone-assisted cleaning. Furthermore, the reaction mechanism of Oxone activation by CoFCM was proposed from the results of the electron paramagnetic resonance (EPR) and radical scavenger experiments. [ABSTRACT FROM AUTHOR]

The residues of sulfonamides and their metabolites can not only give rise to the generation of resistant bacterial/gene, but also have negative impacts on both human and ecosystem. In this work, the oxidation of sulfadiazine (SDZ) using permanganate as an oxidizer was comprehensively investigated, including the degradation kinetics, pathways and byproducts toxicity evaluation. In general, the oxidation of SDZ follows the pseudo first-order kinetics with the rate constant of 0.00168–0.498 min −1 . The activation energy was calculated to be 58.7 kJ mol −1 based on Arrhenius equation. Higher SDZ removal rate can be achieved under the lower pH condition, and the removal rate was decreased accompanying with increasing pH from 3.76 to 8.80. The presence of humic acid at low concentration can accelerate SDZ oxidation rate. Six oxidized byproducts were identified and the plausible oxidation pathways were also proposed. The quantum chemistry calculations indicate that S (2), N (14) and C (16) were more likely to be attacked, which were consistent with the proposed pathways. Furthermore, the toxicity evaluation of the oxidation byproducts suggests that the toxicity of three byproducts (i.e. 2-aminopyrimidine, 4-nitro-N-(pyrimidin-2-yl) benzene sulfonamide and 4-(2-iminopyrimidin-1(2H)-yl) aniline) was higher than parent compound. Despite of complete removal by permanganate, the byproducts that generated by SDZ were even more toxic than parent compound. Therefore, more attentions should be paid to application of permanganate to remove sulfadiazine and further risk assessments should be made to transformed byproducts. [ABSTRACT FROM AUTHOR]

A novel mesoporous graphitic carbon nitride/titanium dioxide (mpg-C 3 N 4 /TiO 2 ) nanocomposite was successfully synthesized and incorporated into polysulfone (PSf) matrix to fabricate photocatalytic membranes. This study aimed to explore the photocatalytic ability of the novel nanomaterial membrane in degrading the antibiotic sulfamethoxazole (SMX) under solar light. The structural and morphological properties of the mpg-C 3 N 4 /TiO 2 nanocomposite and membrane were characterized using various techniques. The SMX photocatalytic degradation performance, pathway and mechanism by mpg-C 3 N 4 /TiO 2 photocatalytic membrane reactor (PMR) were systematically investigated using HPLC and LC-MS/MS. As a pharmaceutically active compound, SMX was transformed into 7 kinds of non-toxic and pharmaceutically inactive byproducts by the innovative PMR technology. SMX removal efficiency of the membrane PSf-3 (with 1% mpg-C 3 N 4 /TiO 2 loading) was the highest over the 30 h consecutive irradiation. Meantime, the membrane didn’t affect the SMX photodegradation, and the structure was able to provide stable support with high integrity and flexibility after solar irradiation. The developed membrane has a great potential to be applied in water treatment industry. [ABSTRACT FROM AUTHOR]

Nanozymes, as a robust alternative to natural enzyme, usually suffer from unsatisfactory catalytic efficiency and limited modulating flexibility. Herein, we proposed a novel strategy to conquer these disadvantages relying on the facet-selective response of external trigger molecule which boosts the oxidase-like catalysis of nanoceria. Results indicate that the trigger molecule (i.e., sulfate ion) prefers to bind to the rod-like nanoceria (on its unique {1 1 0} facets) rather than nanopolyhedra or nanocubes. Sulfate ion-treated CeO 2 nanorods (SO 4 2− /CeO 2 NRs) became modulatable oxidase mimetics of high efficiency, and the catalytic efficiency ( k cat / K m ) of SO 4 2− /CeO 2 NRs improved by nearly 20-fold (versus that of the naked CeO 2 NRs) for 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation. This modulating strategy, together with the mechanism behind, is finally applied to develop colorimetric biosensors, which paves the way for embedding the system in biological and environmental networks. [ABSTRACT FROM AUTHOR]

A synthetic hormone, 17α-ethynylestradiol (EE2), has received much attention due to its widespread occurrence and adverse effects on aquatic animals. The removal of EE2 from water has been very challenging mostly because of its low concentration in environmental waters. Here we report a simple and novel approach for concentrating EE2 through adsorption and elution using microporous polyethersulfone (PES) hollow fiber membrane in a cross-flow filtration system, which can be easily scalable for practical applications. Our results showed that microporous PES hollow fiber membrane has a high EE2 adsorption capability (∼100% from water containing 20 μg/L of EE2) and the adsorbed EE2 could be eluted using a small volume of 10% ethanol solution to achieve a recovery efficiency of 75.9 ± 8.5%. We further demonstrated that the PES hollow fiber membrane maintained ∼100% removal of EE2 throughout five cycles of adsorption and elution. Our results from molecular simulation suggest that the strong affinity between PES and EE2 is mainly attributed to the π- π interaction and the hydrogen bonding. This proof-of-concept demonstrates for the first time that PES hollow fiber membrane system can remove EE2 at low concentrations, and elute EE2 solutions at a much higher concentration over multiple cycles in a sustainable and environmentally-benign condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • ∼85 nm spaced nanorods array timely switches macrophages from M1 to M2 phenotype. • Interrod spacing switches MΦs to M2 phenotype via the FN-integrin β1 -Akt1 pathway. • M2 cytokines enhanced by arrays facilitate osteogenesis via BMP2-TGF-SMAD pathway. Osseointegration is initiated by immune cell-derived inflammatory responses to the surfaces of implanted materials. However, the bio-molecular mechanisms by which nanotopographic features of implant surfaces immunomodulate osseointegration remain to be clarified. To this end, herein, three kinds of TiO 2 nanorod-like arrays on Ti with the interrod spacing of ∼0, 45 and 85 nm, termed as S0, S45 and S85, respectively, were hydrothermally grown, and their actions on the polarization of macrophages (MΦs) and MΦs-mediated contact osteogenesis of bone marrow-derived mesenchymal stromal cells (BMSCs) were explored, especially the involved signaling pathways. Compared to pure Ti (namely P-Ti), the nanorods-arrayed Ti activated FG-integrin α M β 2 -IKK-NF-κB signaling pathway in the adhered MΦs at initial 6 h while FN-integrin α 5 β 1 -PI3K-Akt1 pathway since 24 h, accelerating the transition of MΦs from pro-inflammatory (M1) to anti-inflammatory (M2) phenotype. With the cytokines secreted by M2 cells, the coatings activated the BMP2-TGFβ1-SMAD signaling pathway to enhance osteogenic differentiation of the recruited BMSCs in vitro. Also, the nanorods-coated Ti induced a proper immune microenvironment and accelerated bone apposition in rabbit tibia marrow cavities in vivo. Furthermore, owing to the favorable capacity of osteoimmunomodulation, the ∼85 nm spaced nanorods-arrayed coating exhibited satisfactorily in orchestrating osteogenic differentiation in vitro and in vivo. This work provides insights into nanotopographic features of implant surfaces immunomodulating contact osteogenesis. [ABSTRACT FROM AUTHOR]

• An acid-stable polyamine NF hollow fiber module was prepared for phosphorus recovery via the IP method. • Tannic acid interlayer was first constructed onto the PES substrate to assist the spreading of the aqueous phase. • The resultant NF membrane shows only 9.6% rejection of phosphorus, alongside over 93.5% rejection of metal ions at pH 2. • Membrane water permeability can reach 20.3 LMH/bar. The hazardous heavy metals coexisting with phosphorus-containing sewage sludge seriously limit phosphorus recovery. Nanofiltration (NF) membrane, which can selectively separate heavy metals and phosphorus, has a promising potential for recovering high-quality phosphorus from sewage sludge. In this work, we utilized the undissociated form of H 3 PO 4 at pH <2 and customized an acid-stable polyamine NF membrane via interfacial polymerization (IP) for separating phosphorus and heavy metals under acidic conditions. An interlayer formed via co-deposition of tannic acid (TA) and diethylenetriamine (DETA) was firstly coated onto the polyethersulfone (PES) hollow fiber module to assist the spreading of aqueous phase on the substrate surface. Consequently, a tight and positively charged polyamine layer with a mean pore size of 0.77 nm was successfully constructed on the PES substrate, which is smaller than that of the membrane without interlayer (1.39 nm). This polyamine membrane maintained excellent stability during 15-day acid testing with 0.1 M HCl as feed solution. When it was used to recover phosphorus at acidic condition (pH 2), the phosphorus rejection of the NF membrane was only 9.8 %, much lower than that at neutral pH (46.7 %), which is due to the fact that most phosphorus existed in the undissociated form of H 3 PO 4 at pH 2. Meanwhile, given the fine-tuning pore size and Donnan exclusion effect of this membrane, it could effectively retain 96.9 % of Mg2+ and over 93.5 % of most heavy metal ions such as Pb2+, Cu2+, Fe3+, Zn2+, and Cr3+, alongside outstanding water permeability of 20.3 LMH/bar at 2-bar operation pressure. This result demonstrates the potential of our homemade polyamine membrane in phosphorus recovery. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microfiltration PTFE hollow fibres were transformed into durable, high value OSN membranes. • A PEI/PIP based polyamide thin film was successfully synthesized on PTFE hollow fibre substrates. • A two-time interfacial polymerization was conducted to obtain a defect-free polyamide layer. • The resultant membranes could withstand strong aprotic solvents like DMF and DMSO. • The membranes had high solute rejections, of up to 95 % methyl orange (327 Da) rejection in DMF. Polymeric membranes have been extensively studied for organic solvent nanofiltration (OSN) but many fail to show sufficient chemical resistance in strong solvents like dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). This study focuses on harnessing the outstanding chemical resistance of polytetrafluoroethylene (PTFE), to develop polyamide-PTFE thin film composite (TFC) membranes that are resistant to such aprotic solvents. A defect-free polyamide thin film layer was successfully synthesized on the microfiltration PTFE hollow fibre substrates, overcoming challenges such as large and uneven pore size, and hydrophobicity of the PTFE substrates. A simple polydopamine (PDA) coating was carried out to improve the substrate's hydrophilicity prior to the polyamide synthesis via interfacial polymerization (IP). Polyethyleneimine (PEI) and trimesoyl chloride (TMC) were used as the monomers and a two-time IP method was employed to obtain a defect-free polyamide coating. The synthesized membranes showed high acetonitrile (ACN) and DMF permeabilities of 7.94 and 3.70 lm−2h−1bar−1, respectively, with acid fuchsin (585 Da) rejections of > 90 %. The molecular weight cut-off (MWCO) of the membranes could be further reduced to ∼300 Da by the addition of piperazine (PIP) monomers. The membranes also showed excellent stability and performance in a 72-hour OSN test performed in DMF indicating their great potential in effective molecular separation in harsh solvents. This study demonstrates how a simple modification and coating technique can transform commercially available microfiltration PTFE hollow fibres into durable and high value OSN membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel alternating spin-spray electrospun nanofibrous scaffold with embedded MOFs. • Anionic dye removal of >99% with water permeability up to 8808 Lm−2h−1bar−1. • High throughput of up to 500 mL of permeate in 40 min whilst operating at 2 psi. • Robust membrane scaffold maintaining > 99% dye removal over 3 regeneration cycles. Adsorption is an attractive process for wastewater treatment, owing to its technical simplicity and ease of implementation. However, the adsorption process is often challenged by unoptimized efficiency, especially when the high-performing adsorbents are compacted into a packed bed column design. Herein, an electrospun nanofibrous porous scaffold is rationally designed to fractionate packing and reduce hydraulic resistance of a chromium benzene dicarboxylate-based metal–organic framework (MIL-101(Cr)) used as an adsorbent for the removal of anionic dyes. The MIL-101(Cr) adsorbent was in situ loaded via a spray-assisted method onto the electrospun scaffold in an alternating spray-and-spin fashion to deconstruct the packing and offer fractionated loading of the adsorbent materials. As compared to its unfractionated counterpart, well-fractionated MIL-101(Cr) exhibited an order of magnitude higher adsorption capacity over time with high dye removal towards Methyl Orange (MO), Acid Fuchsine (AF,) and Rose Bengal (RB). In a single pass filtration experiment, the PAN/MOF(50) ESNF-AS scaffold performed at 8808, 5066, and 7574 Lm−2h−1bar−1 water permeabilities at 2 psi with exceptional > 99 % dye removal for MO, AF, and RB dye, respectively. In addition, the spent MIL-101(Cr) adsorbent in the electrospun scaffold was able to be regenerated by alkaline and acid washing and showed good recyclability, suggesting the chemical and structural robustness of the scaffold design. This approach is highly versatile and can be adopted on different adsorbents to target the removal of different contaminants from wastewaters for a more sustainable future. [ABSTRACT FROM AUTHOR]

Arsenic, a common highly-toxic pollutant, is mainly associated with the hydrous ferric oxides in soils and minerals. A possible mechanism for arsenic mobilization is the reductive dissolution of iron (hydr) oxides. In this paper, the possibilities of iron-reducing bacteria Shewanella oneidensis MR-1 and Shewanella sp. strain MR-4 in mobilization, oxidization and methylation of arsenic were investigated. Under laboratory conditions, the dynamics of As- and Fe-release from arsenopyrite and scorodite under microbial activities, the transformation of arsenic release from iron minerals and the environment factors affecting the arsenic release and transformation during reactions were examined. The aqueous concentrations of different forms of As were determined by a liquid chromatography–atomic fluorescence spectrometry (LC–AFS) and the new surface morphology of iron minerals was also measured and characterized using scanning electron microscopy (SEM) and X-ray diffractometry (XRD). Results indicated that As could be dissolved from arsenopyrite or scorodite and oxidized or even methylated quickly in the presence of Shewanella strains. The transformation of arsenic forms were affected by the culture temperatures, pH of environment medium, and spiked Fe(III) content in the solutions. Moreover, solid-phase analysis revealed that the morphology and mineralogy in the solid-phase products were changed, such as many wrinkle-shaped gullies were formed on surfaces of iron minerals. The amount of secondary precipitates also increased with time. The As mobility could be enhanced by the activity of dissimilatory iron-reducing bacteria in the environment. This study provides insights into in situ remediation of As pollution. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) provides performance of ion removal via electrodes with high porosity and confined nanopores. Hitherto, the main emphasis has been on the enhancement of removal efficiency based on a lab-scale setup, neglecting anomalous dynamic and dielectric properties in confinement. This work was completed to reveal structural and dynamic properties of hydrated ions in a 3-nm nanopore of a CDI electrode using molecular dynamics simulation based on the nonpolarizable (SPC/E) and polarizable (SWM4-DP/-NDP) force fields. It was shown that all the force fields caused marginal differences in hydration structure but greater differences in ionic dynamics. Furthermore, dielectric constants obtained from all the force fields were lower in confinement than in bulk, although they were slightly higher in the polarizable models. Angular distributions of water bonds and dipole vectors revealed this decrease was caused by the restriction of water rotational dynamics and hence a depression of dipolar fluctuations. Hydrogen bond lifetimes indicated that higher availability of hydrogen bonding sites also facilitated increasing the dielectric constant as it allowed a more frequent "switch" of the fast hydrogen bond. Both the angular distribution and the hydrogen bonding contributed to the slightly higher dielectric constant in the polarizable model than in the nonpolarizable model. Our local sensitivity analysis of a ion transport model revealed that the dielectric constant greatly determined ion transport in the electrode, although the diffusion coefficients of typical ions had limited influences. This work provides fundamental theories and great implications for the theoretical analysis of ion electrosorption in a CDI electrode and enhances its application in water treatment. [Display omitted] • Ionic structure and dynamics were investigated on a molecular scale. • Anomalous dielectric constants were found based on the MD simulations. • Hydrogen bonding network clearly explains the anomalous dielectric constant. • The dielectric constant greatly influences on ion transport in a CDI system. [ABSTRACT FROM AUTHOR]

[Display omitted] • The QAs bearing pH responsive copolymer were synthesized. • Self-adaptive antibacterial coating were prepared on titanium implants. • The coating displays pH responsive antibacterial activity. • The modified titanium implants shown osseointegration-promoting performances. The development of responsive antibacterial implants is of high significance for the treatment of implant-associated infections. In this study, a self-adaptive antibacterial Ti-based implant with pH-sensitive coating was flexibly designed and constructed, with the dual functions of antibacterial and promoted osseointegration. The pH-sensitive antibacterial copolymer containing cationic quaternary ammonium salts (QAs) and carboxyl groups was firstly synthesized. Then, the prepared copolymer was coated on the surface of Ti metal by a simple layer-by-layer (LBL) self-assembly method to construct an antibacterial coating. The surface charge reversal was caused by the acidic microenvironment induced by the infected bacteria. The positively charged QAs possessed excellent antibacterial property against E. coli and S. aureus in vitro. The negatively charged carboxyl groups promoted the adhesion, proliferation and osteogenic differentiation of MC3T3-E1 cells in vitro. And the results of a S. aureus infection rat model further confirmed that the coated screws possessed good abilities of antibacterial and anti-inflammatory of implantation, and showed good osteointegration performance compared with the control ones. This strategy of self-adaptive antibacterial coating will provide a potential application for the prevention of Ti implant-associated bacterial infections. [ABSTRACT FROM AUTHOR]

[Display omitted] • SnO 2 and CeO 2 nanoparticles were firstly used to modified graphene electrode. • The synergistic effect of bimetals enhanced the electron transfer of electrode. • DFT calculation substantiated the increased adsorption energy and electron transfer. • The developed sensor achieved a very low detection limit of 0.01 μg/L for Cd ion. A novel laser-induced graphene (LIG) electrode modified with SnO 2 and CeO 2 nanoparticles (NPs) was created to detect Cd(II) ions via differential pulsed anodic stripping voltammetry (DPASV). Transmission electron microscopy (TEM), scanning electron microscopy (SEM), infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and contact angle (CA) analyses were used to characterize the physical and electrochemical properties of the electrode. Both the electrochemical activity and adsorption capacity of the carbon electrode were significantly enhanced. Due to the synergistic effects of SnO 2 and CeO 2 NPs, the modification enhanced the transfer of free electrons on the electrode surface, increasing the electrode sensitivity and accelerating the response speed in the detection process. The use of poly-aminobenzene sulfonic acid (p-ABSA) further increased the conductivity of the electrode. The enhanced adsorption energy and electron transfer properties of the modified electrode were also substantiated by density functional theory (DFT) calculations. Parameters such as Sn/Ce ratio, deposition time, number of polymerization cycles of p-ABSA and solution pH were optimized to determine the best detection conditions for Cd(II) ions. Under optimal conditions, our sensor showed a broad linear concentration range (0.1 ∼ 160 μg/L) with a low detection limit (0.01 μg/L). This sensor was also successfully applied for detection of Cd(II) ions in groundwater and tap water. Recovery rates ranged from 94 to 111% with a relative standard deviation (RSD) less than 6.06%. This sensor has good anti-interference ability, reproducibility and stability. Our results provide a promising sensor technique for efficient and rapid in situ monitoring of Cd(II) ions in aquatic environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biomimetic injectable hydrogel embedded with Au/MOF composites was synthesized. • Au nanoparticles could improve visible light-driven photocatalysis of ZIF-8. • The hydrogel kills bacteria under visible light while promoting wound healing. Antibiotic resistance of bacteria is one of the greatest threats to wound healing, which necessitates the need for alternative strategies to eradicate bacteria in the wound site. Taking advantage of the reactive oxygen species (ROS)-generating capability of photocatalytic semiconductor nanomaterials under light irradiation, here we report a biomimetic injectable double-network hydrogel using oxidized sodium alginate and carbohydrazide-modified methacrylated gelatin that mimics the extracellular matrix, which was further embedded with semiconductor-like metal–organic frameworks (MOFs) encapsulating noble metal nanoparticles (Au@ZIF-8). This composite design substantially improved the ROS generation under visible light actuation (>400 nm) compared with pristine ZIF-8, owing to its reinforced light absorption and charge carrier separation by the Au-mediated surface plasmon resonance (SPR) and Schottky junction. The composite hydrogels not only showed remarkable bactericidal activity against both E. coli and S. aureus , but also significantly accelerated wound healing at optimal safety. Altogether, this injectable double-network hydrogel could simultaneously provide antibacterial and pro-healing capabilities, which may have translational potential as wound dressing materials. [ABSTRACT FROM AUTHOR]