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• A flexible aqueous Al-ion battery was reported for the first time. • The flexible Al-ion battery exhibits exceptional flexibility and safety. • The Al-ion battery delivers excellent electrochemical cycling stability. • This work paves the way for Al-ion battery application in wearable electronics. With the fast development of flexible and wearable electronics, the design of secondary energy storage system based on aqueous metal ion battery with outstanding flexibility, safety and low cost is critical for their practical application. As low-cost alternatives to lithium ion battery, multivalent metal ion technologies including Mg2+, Zn2+, Ca2+, and Al3+ are investigated increasingly in the past few years. The investigation based on Al-ion chemistry is also underway considering the aluminum's advantages of natural abundance, small ion size together with three-electron-redox properties. Herein, a flexible aqueous Al-ion battery is successfully fabricated for the first time with copper hexacyanoferrate cathode and polypyrrole (PPy) coated MoO 3 anode sandwiched by gel electrolyte. The as-assembled Al-ion battery based on intercalation chemistry exhibits an excellent cycling stability of 83.2% capacity retention after 100 cycles and good rate capability benefiting from the conductive PPy coating layer on MoO 3 anode. Besides, the battery demonstrates impressive flexibility and safety to sustain various deformations and mechanical abuse including bending, squeezing, folding, twisting as well as arbitrary drilling and tailoring into any desired shapes. Obviously, the flexible aqueous Al-ion battery developed in this study paves the way of multivalent metal ion battery as energy storage device towards various wearable electronics. [ABSTRACT FROM AUTHOR]

• A unique silane coupling agent derivative-coated Zn anode with ion perselectivity was demonstrated. • This modified Zn anode greatly restrained side reaction with desolvation of [Zn(H 2 O)6]2−. • Versatile coating with tightly contact of nano particles and organic network contributed to full-cell long cycling life. Although zinc anodes are extensively adopted to meet aqueous energy storage, serious dendrite formation and side reaction resulting in inferior lifetime have hindered the application. In this work, a unique interfacial engineering is proposed by a self-assembled artificial layer tightly contact to the surface of zinc anode with Zn2+ permselectivity. Such artificial layer via a facile hydrolysis consists of nano inorganic particles well dispersed in organic network. The screening for the bound water of Zn2+ enables excellent anticorrosion during cycling and rest situation. Meanwhile, the modified zinc anode can reduce the Zn2+ nucleation barrier for uniform distribution, which is beneficial to dendrite suppression. Consequently, the modified zinc anodes in both symmetric and full cells exhibit prominently electrochemical reversibility. Specifically, with a cycling area capacity of 3.0 mAh cm−2 at 1.0 mA cm−2, the modified zinc anode can tolerate superior plating/stripping behavior over 1000 h. When it is coupled with vanadium pentoxide cathode, the performance advantage of the modified full-cell is still impressive and high-capacity retention of ∼84 % after 1200 cycles is achieved. [ABSTRACT FROM AUTHOR]

• A photocatalytic process was used to degrade tetracyclines in biogas slurry. • TC, OTC and CTC removal reached 94.99%, 88.92%, and 95.52% under optimum conditions. • Adsorption of tetracyclines was increased by the concentration of biogas slurry. • Flocculation pretreatment can improve photocatalytic efficiency. • pH, total solid and chroma of biogas slurry significantly affect photocatalysis. The high concentration of antibiotics in liquid digestate makes it unviable for use as fertilizer on farmland. This study designed a system for antibiotic degradation and applied the photocatalytic process to degrade tetracyclines in liquid digestate. The effects of different operational variables (e.g., radiation source, TiO 2 concentration, photocatalytic time, temperature, and depth of Liquid digestate) on the removal of tetracyclines were analyzed and optimal operation conditions were obtained. The correlation between the physicochemical properties of liquid digestate and tetracyclines removal was also analyzed. The results indicate that a high pressure mercury lamp is effective for the photocatalysis of tetracyclines in liquid digestate. Tetracyclines removal increased with increasing TiO 2 concentration, photocatalytic time, and decreasing liquid digestate depth. However, the temperature of liquid digestate had little effect on the removal of tetracyclines. Under the high pressure mercury lamp, the removal of tetracycline, oxytetracycline, and chlortetracycline reached 94.99%, 88.92%, and 95.52%, respectively, under the optimum conditions (TiO 2 concentration of 1.0 g/L, liquid digestate depth of 20 mm, and photocatalytic time of 120 min). In addition, the tetracyclines concentration, pH, total solid, and chroma of liquid digestate all had significant effects on the photocatalytic process. Flocculation pretreatment can improve photocatalytic efficiency by reducing the chroma, pH, and TS of liquid digestate. Our findings show that photocatalysis is an effective method for removing antibiotics in liquid digestate and has the potential for application to pollutant removal. Furthermore, our results provide conditions for the popularization and application of apparatus for the degradation of antibiotics in liquid digestate. [ABSTRACT FROM AUTHOR]

• The NH 3 -SCR activity of metal doped OMS-2 is higher than that of undoped K-OMS-2. • The NH 3 -SCR activity over M-OMS-2 increased with the Brønsted acid sites. • Na-OMS-2 showed optimal NO conversion due to the presence of more Brønsted acid sites. • The Brønsted acid sites and lattice oxygen play important role in NH 3 -SCR reaction. Different metal cations (Li+, Na+, Mg2+, Ca2+, Al3+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, and Ag+) were doped into the OMS-2 material via "one-pot" refluxing approach to investigate the influence of metal cations doping on the structure of OMS-2 and on the activity of selective catalytic reduction (SCR) of NO x with NH 3. The catalytic performance over the doped M-OMS-2 catalysts increased with the Brønsted acid sites. Na-OMS-2 displayed the best deNO x performance, which is primarily due to the higher surface area, reducibility and Brønsted acid sites. Kinetic results demonstrate that the activation energy (E a) of Na-OMS-2 catalyzed NH 3 -SCR reaction is evidently lower than that of the undoped K-OMS-2 catalyst owing to a larger number of NH 3 adsorbed on Brønsted acid sites and more facile activation of NH 3. Meanwhile, the Na+ loading of Na-OMS-2 is further optimized for the NH 3 -SCR reaction, the results indicate that the Na-OMS-2 with Na/(Na + Mn) ratio of 0.03 exhibits the best activity because of the higher reducibility and more acid sites. A feasible NH 3 -SCR mechanism is proposed to highlight the importance of the Brønsted acid sites and the lattice oxygen. [ABSTRACT FROM AUTHOR]

[Display omitted] • IM-BTO membrane is prepared by homogenization spin coating strategy. • Homogenization spin coating achieves porous structure and catalytic site exposure. • IM-BTO membrane has high water flux and photocatalytic self-cleaning ability. • The selective coefficient of IM-BTOM relative to BTOM can reach 2.66. Photocatalytic membrane technology is a promising technology for advanced water treatment. However, as a simple, fast, and stable spin coating method for photocatalytic membrane preparation, the spin coating solution often used in spin coating can cause the pore plugging on the membrane surface and encapsulates photocatalysts, which seriously affects the flux of the membrane and the exposure of the photocatalytic active site. Here, this work adopted a homogenization spin coating strategy, using polyvinylidene difluoride (PVDF) solution as the spin coating solution to prepare the highly exposed imprinted bismuth titanate porous photocatalytic membrane (IM-BTOM). Due to the same composition of PVDF solution as the PVDF substrate membrane, IM-BTOM basically retained the good porous structure of the membrane. The homogenization spin coating strategy not only endowed IM-BTOM with high flux (4545.45 L m-2h−1 bar−1), but also prevented the encapsulation of IM-BTO powder materials, fully exposing the photocatalytic active sites, thereby obtaining better photocatalytic ability and selectivity. The degradation rate of tetracycline with IM-BTOM was nearly three times that with the conventional cellulose acetate spin coating membrane. Meanwhile, the existence of imprinting cavities also endowed IM-BTOM with high selectivity for the target pollutant, with a selectivity coefficient of up to 2.66. This work provides a new idea for preparing high-efficient photocatalytic membrane by spin coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Z-scheme silver phosphotungstate/polyimide photocatalyst was synthesized. • Self-assembly and in-situ solid-phase thermal polycondensation were utilized. • Keggin units act as the shuttle redox mediators for Z-scheme photocatalytic system. • The target photocatalysts exhibit enhanced visible light photocatalytic activity. • Oil-H 2 O mixed system can enhance the degradation process of AFB1. Silver phosphotungstate/polyimide (MAPI) photocatalyst was successfully synthesized by a multi-step strategy combining the self-assembly and in-situ solid-phase thermal polycondensation. The construction of MAPI photocatalysts and their photocatalytic activity were investigated. The polyimide (PI) in MAPI photocatalysts obtains the weakened π-π stacking structure and more dendritic crystalline structure. However, the POMs-π interactions, charge-transfer form in conjugated organic ligands-modified polyoxometalate (POMs) materials, and the close contact between main components are beneficial to the charge transfer in MAPI photocatalysts. The coordination interactions of Keggin anions and organic ligands allow the Keggin units released during the thermal treatment process to act as shuttle redox mediators for Z-scheme heterojunction photocatalysts. The changes related to the physicochemical and interfacial interactions of the components enable the MAPI photocatalysts to exhibit the enhanced photocatalytic activity. Pristine PI shows little activity for photocatalytic degradation of Aflatoxin B1 (AFB1) under visible light (λ ≥ 420 nm) irradiation, but the rate constant k of 5-MAPI was 7.34 and 4.46 times than that of pristine AgPW and P25, respectively. The presence of H 2 O and the transfer behavior of AFB1 in the oil-H 2 O mixed system significantly promoted the photocatalytic degradation efficiency of AFB1 in peanut oil. Z-scheme charge transfer path and the photocatalytic degradation pathway of AFB1 were also proposed. Combined with the density functional theory (DFT) calculation results, AFB1 will be firstly degraded by the ·OH-induced cycloaddition reaction at the C19 = C20 of furan ring. Subsequently, methoxy (C23-O22), furan ring, lactone ring and carbonyl group (C9 = O10) are degraded in sequence. This work can provide some interesting insights into the construction of polymer/insoluble POMs photocatalysts and the photocatalytic degradation of exogenous harmful substances in vegetable oil. [ABSTRACT FROM AUTHOR]

• Organic-inorganic Ov-PVO/G heterostructures are prepared via a ball-milling approach. • The heterostructures contain expanded interlayer spacing, oxygen vacancy and heterointerface. • Freestanding Ov-PVO/G heterostructure cathodes with high mass-loading are fabricated. • The three-in-one Ov-PVO/G heterostructures exhibit accelerated reaction kinetics. • The freestanding Ov-PVO/G heterostructure cathodes for AZIBs deliver high areal capacity. Aqueous Zn-ion batteries (AZIBs) have great potential in large-scale energy storage, however, developing suitable cathodes with high energy/power densities remains highly challenging. Herein, a unique organic-inorganic heterostructures (denoted as O v -PVO/G) of poly(3,4-ethylenedioxythiophene) intercalated V 2 O 5 nanocrystals anchored on few-layer graphene by a simple and scalable ball-milling approach are demonstrated for high areal-capacity AZIBs cathodes, in which, adjusted interlayer spacing, abundant oxygen vacancies and robust heterointerfaces can be simultaneously constructed. Moreover, the feature of being well dispersed in different polar solvents (H 2 O, NMP, etc.) enable facile incorporation of the O v -PVO/G heterostructures into conductive networks of single-walled carbon nanotubes to fabricate freestanding composite cathodes. Electrochemical measurement and first-principles calculations indicate that such "Three-in-One" heterostructure can significantly enhance Zn2+ adsorption/desorption, electrical conductivity and charge transfer due to strong synergy, thereby exhibiting high-capacity and accelerated reaction kinetics during cycling. Specifically, at a practical mass loading of 12.0 mg/cm2, the freestanding O v -PVO/G cathodes show a high areal-capacity of 6.1 mAh/cm2 at 2.4 mA/cm2 and works stable with an area-capacity of 1.63 mAh/cm2 at 120 mA/cm2 after 500 cycles. More importantly, flexible soft-packaged AZIBs based on 3×3 cm2 high mass-loading O v -PVO/G cathodes deliver record-high and stable electric energy beyond 21.5 mAh at different bending states. This work paves a more promising way to practical application of high-performance AZIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Al 2 O 3 /C nanofiber skeleton enhanced electron and thermal transport. • The OSi enhanced LiPSs suppression and electrolyte retention. • PE‖Al 2 O 3 /C@OSi assembled cell showed excellent safety under thermal gradient. • PE‖Al 2 O 3 /C@OSi assembled cell showed high-performance under lean-electrolyte. The development of lithium-sulfur (Li-S) batteries is dogged not only by severe limitations in cycling and rate performances arising from the shuttle effect of lithium polysulfides (LiPSs) but also severe degradation under harsh evaluation conditions of high sulfur loading, lean-electrolyte, and prominent thermal gradient. To achieve high performance and safety in Li-S batteries, a flexible and multifunctional integrated interlayer consisting of dual-functional alumina/carbon (Al 2 O 3 /C) nanofiber skeleton and organosilicon (OSi) filler is fabricated. Electrically and thermally conductive nanofibers are continuous and interlaced, enhancing the reutilization of LiPSs and the homogenization of temperature gradient through constructed dual-conductive networks. The interval-filled OSi helps in the diffusion of LiPSs and the absorption and retention of electrolytes, providing significant support to stabilize the Li-S batteries for long-term cycling. As a result, considerable enhancements in cycle stability and rate performance either under a high sulfur loading of ∼5.5 mg cm-2, low electrolyte/sulfur (E/S) rate of 4 μL mg-1, or artificial temperature gradients are achieved for a typical sulfur/carbon black cathode simply by incorporating multifunctional Al 2 O 3 /C@OSi interlayer. The new design and configuration of the interlayer may practically be used in high-energy applications since it can effectively address severe limitations of the current Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • E–TiO 2 @rGO with OVs were prepared through crystal defect engineering. • Mixed crystal and OVs enhanced electron-hole pairs separation efficiency. • E–TiO 2 @rGO improved 2,4,6-TCP dichlorination process and degradation efficiency. • The toxicity of 2,4,6-TCP and its intermediates was evaluated via ECOSAR and DFT. Chlorophenolic pollutants pose serious threats to the aquatic ecosystem. Photocatalysis technology has broad prospects for decontamination. In this work, MXene-derived TiO 2 nanocomposites with mixed-crystal characteristics and oxygen vacancies (OVs) (E–TiO 2 @rGO) were successfully synthesized by atmosphere modulation. Compared with commercial TiO 2 and N 2 –TiO 2 @rGO (anatase phase), the rate constants of E–TiO 2 @rGO (0.06874 min−1) over 2,4,6-trichlorophenol (2,4,6-TCP) degradation increased 4 and 1.3 times, respectively. The enhanced photocatalytic performance was attributed to the co-existence of anatase and rutile phases. On the one hand, the mixed-crystal phase narrowed the band gap, broadening the light absorption range. On the other hand, it induced the generation of OVs, which has been demonstrated by DFT calculation. The presence of OVs improved the adsorption and activation of O 2 and H 2 O molecules, beneficial for the formation of active free radicals. In addition, the incorporation of rGO promoted the separation of electron-hole pairs. The Gibbs free energy of 2,4,6-TCP degradation revealed that the OVs and mixed-crystal could reduce the energy barrier of the rate-determining step, thereby boosting the dichlorination efficiency of 2,4,6-TCP. The superoxide free radical (O 2 −) was determined as the dominant active species. Finally, a possible mechanism of 2,4,6-TCP degradation with E–TiO 2 @rGO was clarified clearly. The proposed mixed-crystal defect engineering represents a novel strategy in the design and synthesis of photocatalysts. [ABSTRACT FROM AUTHOR]

• Zincophilic layer were constructed on Zn anode via simple soaking strategy. • The artificial layer can regulate Zn2+ flux as verified by COMSOL simulation. • The decorated Zn anode displays ultralong lifespan over 4800 h. • Dendrite-free Zn anode were achieved with high CPC of 6900 mAh cm−2. Aqueous zinc-ion batteries have been highly valued for their high safety and environmental friendliness. However, the notorious Zn dendrite growth derived from uneven distribution of electric fields and side reaction at the electrolyte–anode interface critically limited the lifespan of aqueous zinc-ion batteries. Herein, uniform zinc deposition were achieved by construction of interface film with prussian blue 3D open framework, which provide highly zincophilic channel with well-regulated Zn2+ flow tailored on Zn anode surface. The decorated Zn electrode displayed an ultralong plating/stripping cycling life over 4800 h with an ultralow voltage hysteresis (30 mV) at current density of 0.25 mA cm−2. Moreover, the modified Zn||Cu half cell delivers high average coulombic efficiency up to 99.2% for more than 1000 cycles at 0.5 mA cm−2. When coupled with MnO 2 cathode, the full cells demonstrated significantly improved cycling stability with capacity retention of 85.1% after 200 cycles. The facile construction strategy of interface layer with well-regulated Zn2+ flow developed in this work provided promising perspective for the design of long term aqueous Zn battery. [ABSTRACT FROM AUTHOR]

• One-step polyphenol deposition strategy was applied to prepare multifunctional MF membranes. • Modified membranes with large pore sizes exhibited >6 log pathogenic reduction. • Metal ions were in-situ captured and reduced by polyphenol-based surface chemistry. • The membrane system showed effective biofouling prevention under gravity filtration. • Improved hydrophilicity and antimicrobial effects promote antibiofouling performance. In remote industrial areas, access to safe drinking water is often hindered by local water contamination and unreliable infrastructure. Hence, energy-effective water treatment and safe storage technology is vital and highly desirable to tackle complex water pollution caused by heavy metals and pathogenic contaminants for boundary circumstances. Here, we originally engineered a multifunctional gravity-driven membrane system to provide a household-level approach to pathogenic disinfection and biofouling prevention. Facile one-step polyphenol deposition strategy was applied on microporous membranes, tailoring the membrane surface with enhanced positive charge, favorable hydrophilicity and metal-binding ability. When applied in gravity-driven filtration of simulated multi-component wastewater containing heavy metals and pathogenic contaminants, the as-prepared membrane achieved >6 log pathogenic reduction. Metal ions could be in-situ captured and stabilized at membrane interface via natural binding and reduction by polyphenol-engineered surface chemistry, endowing ensuing membranes with improved antibacterial activity. By virtue of enhanced membrane surface properties and antimicrobial synergy, such engineered membrane platform showed potent efficacy in biofilm prevention with 97% reduced ATP content and easy permeation recovery (>90%) in cyclic operation. This study is promising for developing low-energy and easy-to-use membrane system to improve contaminated water sources in remote and underdeveloped areas at household level. [ABSTRACT FROM AUTHOR]

• The deposited layers improved the removal of contaminants and membrane permeability. • The micro fine particles enhanced the hydrophilicity of membrane surfaces. • The micro fine particles decreased adhesion free energy between membrane surfaces and foulants. • The micro fine particles influenced on the biofilm structures. Micro fine particles (micro fine powdered activated carbon (MFPAC) or micro fine powdered zeolite (MFPZ)) were deposited on hydrophobic polyvinylidene fluoride (PVDF) membrane to enhance gravity-driven ultrafiltration performances. A distinct flux attenuation and permeate quality difference were observed between pristine and deposited membrne systems. The results indicated that both MFPAC-PVDF and MFPZ-PVDF membranes exhibited a high pure fluxes, a gentle flux downward trend and a high stable permeate flux compared to the pristine PVDF membrane. Additional, compared to the pristine membrane, the deposited membrane systems exhibited a significantly enhanced removal of TOC, NH 4 +-N, and TN (increased by 48%, 93% and 22% for the MFPAC-PVDF membrane, by 18%, 89%, and 20% for MFPZ-PVDF membrane). The improved performance of deposited membranes were attributed to both the changed initial surface properties and the subsequent biofilm characteristics. Owing to the presence of MFPAC and MFPZ filtration layer, the enhanced hydrophilicity due to the introduction of surface –C-O and –OH groups, as well as the decreased free energy of adhesion between membrane surfaces and foulants, impart deposited memrbanes promising potential of permeability improvement and fouling mitigation. Furthermore, the biofilm amounts and compositions of deposited membranes were also significantly influenced, presenting a reduction of accumulated organic compounds by 40 and 50%, repectively, compared to the pristine membrane, contributing to alleviated membrane fouling. The MFPAC could function as a live bacteria incubator, resulting in a higher bacteria bioactivity and enhanced degradation in the biofilm layer. While The MFPZ was in favour of hydrophilic protein cover to form a hydration shell on biofilm surface, helping to prevent the approach of hydrophobic foulants. [ABSTRACT FROM AUTHOR]