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Wastewater remediation via photocatalysis for the environmentally friendly degradation of organic contaminants has attracted increasing attention in recent years. Nevertheless, the efficiency of such a promising technology is still unsatisfactory due to the low light utilization, poor hydrophilicity, easy aggregation, and difficult recycling of powder photocatalyst materials. In this study, we developed a versatile strategy for the design of superhydrophilic and polyporous nanofibrous membrane with excellent photocatalytic activity and outstanding recyclability via the combination of loading modified photocatalyst and constructing hydrophilic channels in the electrospinning nanofibers. A novel graphitic carbon nitride photocatalyst with the simultaneous introduction of boron-doped and nitrogen-deficient structure (B-C3N4) was synthesized firstly, and then blended with polyethersulfone and Poly(vinylpyrrolidone) (PVP) to fabricate composite nanofibrous membrane via electrospinning technology. After a simple water extraction process to remove PVP, a highly Polyporous and superhydrophilic nanofibrous membrane (PBCN) was obtained. The resulting mesopores and channels existing in the nanofibers could facilitate the diffusion of contaminant molecules, expose more photocatalysis sites of B-C3N4, and finally improve the photocatalytic activity. Especially, thanks to the continuous removal of residue PVP in PBCN, it was provided with a sustaining enhancement of reusability during the repetitive reuse process, which was superior to most of the traditional wastewater remediation materials. In addition, a possible photocatalytic mechanism for degrading organic contaminants by the PBCN was proposed. In this work, we not only prepared superhydrophilic, polyporous and visible light responsive nanofibrous membrane for the photocatalytic degradation of various organic contaminants, but also introduced a novel approach towards the design of advanced nanofibrous materials for diverse catalysis, adsorption and separation applications in environment remediation.

Lithium-sulfur (Li-S) batteries are considered as one of the best future profession power sources owing to their ultrahigh energy density. Nevertheless, the commercialized Li-S batteries is challenging owing to the shuttle effect of lithium polysulfides (LiPSs), poor electronic activity of sulfur and safety issues. In this work, flexible and binder-free 3D porous 1,3,5-triformylbenzene-tris(4-aminophenyl) amine (Tf-TAPA) covalent-organic framework (COF) derived N-doped carbon (CTT)/ 2D transition metal carbides and nitrides (MXene) paper is designed as electronic conductive sulfur host to restrict the LiPSs. To boost the safety of Li-S batteries and further reduce the LiPSs diffusion, all-solid-state Li-S batteries are constructed by utilizing polyethylene oxide (PEO)-based solid electrolyte with low LiPSs solubility and high safety. With the synergistic advantages of porous and electronic conductive CTT, MXene and solid-state electrolyte, the all-solid-state Li-S batteries display excellent safety character and stable cycling stability about 584 mAh g−1 even after 100 cycles.

Synthesis of biomimetic adhesive for achieving robust interface bonding attracts numerous attentions for various applications. Inspired by the metal ions-assisted coacervation mechanism of sandcastle worm glue, novel copolymer/Mn+ complex wet adhesives are synthesized successfully, containing hydrophobic component, bidentate anionic component and temperature sensitive component. The anionic segments in copolymer interacts with different metal ions (Ca2+/Mg2+/Cu2+) in solution through coacervation reaction along with temperature-strengthened dehydration effect, resulting in the formation of biomimetic adhesives. The wet adhesion strength of the biomimetic adhesives is tunable based on the ions species, concentrations and coordination time, while the adhesion mechanisms are analyzed and discussed in details. The biomimetic adhesives not only can be used to tightly bond two solid surfaces underwater, but also is robust and effective in air. For example, current adhesives can firmly bonding various substrates including glass, Si, PTFE and animal bone. More importantly, the biomimetic adhesives are capable of sealing leaky pipes or vessels in harsh wet environment. Due to no dopamine chemistry, current adhesives involve no oxidation problem. We firmly believe this new system would demonstrate promising applications in surface engineering, wet sealing/repairing and tissue engineering.

A challenge for the design of nonlinear polymerization is the full appreciation of the impact of side reactions, demanding the development of modeling techniques to determine the associated kinetic parameters while using the most important experimental responses. Here the combination of computationally inexpensive method of moments (MoM) kinetic simulations and dedicated principal component analysis (PCA) is put forward as a promising strategy to be successful in this respect. Focus is on (radical) vinyl grafting of chains containing unsaturations, selecting styrene (St) as monomer and polybutadiene (PB) as backbone, and low St conversions accounting for diffusional limitations on termination. It is highlighted that the less studied macropropagation cannot be directly ignored and a combined set of experimental responses related to free polystyrene and grafted copolymer (GC) average product properties is recommended for kinetic parameter estimation. This is supported by regression analysis considering in silico generated experimental data compensated for random noise and considering a validated end-chain approximation.

The aim of this study was to quantify the removal of halogenated pollutants (using triclosan as a model pollutant) from aqueous solution by zero-valent iron coupled with a weak magnetic field. We determined the removal efficiency of triclosan from a sodium sulfate solution at different pH values under both aerobic and anaerobic conditions. The removal of triclosan followed pseudo-first-order kinetics in both the presence and absence of a weak magnetic field. The calculated rate constants indicated higher removal efficiencies of triclosan under the aerobic condition compared to the anaerobic condition. In addition, increase of triclosan removal from acidic solutions was achieved with the assistance of weak magnetic field. X-ray diffraction and X-ray photoelectron spectroscopy analysis indicated that FeO(OH) and Fe3O4 were the main aerobic transformation products, suggesting that the zero-valent iron surfaces were completely oxidized. The aerobic and anaerobic transformation products of triclosan were analyzed by liquid chromatography tandem mass spectrometry. The results indicated that the application of a weak magnetic field could be an efficient and cheap treatment process to improve the removal of halogenated pollutants by zero-valent iron, which may be developed for future use.

Superamphiphobic materials are helping with urgent issues due to increasing industrial oil transportation, as well as common oil pollution, which has triggered large interest owing to their high application value and practicability. However, they are difficult to be fabricated because of the peculiarly shaped surface structures and the substrate-dependent property, and hence, their practical applications has been immensely limited. Herein, we prepare a hierarchical superamphiphobic FOTS-SiO2 powder via a reduction reaction and self-assembly functionalization. Owing to the substrate-independent character and excellent super-repellency of the powder, it can be applied to various substrates to fabricate superamphiphobic coatings. The prepared coatings have a wide range of liquids repellency to water, oils, and even to low-surface-tension liquids like 60 wt% ethanol-water solution (25.48 mN·m−1) and n-decane (23.8 mN·m−1). What’s more, the coatings also own great water/oil-proofing ability, excellent chemical stability, antifouling and self-cleaning property. Apart from these general performances, we find that the coating has terrific anti-crude-oil-adhesion property, which endows it a new application—crude oil transportation with high efficiency (2.9 ± 0.09 mL/s). All of these advantages will endow the superamphiphobic FOTS-SiO2 particles with broad application prospects, including foodservice industry, petroleum exploitation, crude oil transportation industry, and so on.

Precisely striking the bacterially infected site and avoiding damage to healthy tissues is vital for bacterial infection therapy. Herein, an intelligent antibacterial platform that triggers the aggregation of gold nanoparticles (AuNPs) on bacterial surface based on the acidic environment of bacterial infection was developed. Also, the AuNPs functionalized with an acidity-triggered moiety (Pep-DA) exhibited a charge-convertible properties to target bacterial infection sites. The positively charged acidity-triggered AuNPs endowed the AuNPs aggregate on negatively charged bacterial surface in the infected site rather than in healthy tissues, achieving the threshold to interparticle plasmonic coupling effect among AuNPs, and killing bacteria accurately under NIR irradiation light. This acidity-triggered aggregation strategy provides an excellent therapeutic mode for treating focal bacterial infections with no critical damage to healthy tissues.

Tin selenide (SnSe2) is an ideal anode in lithium-ion batteries (LIBs) owing to its high theoretical capacity and high conductivity for both electrons and ions. Herein, we design a unique heterostructure with 2D SnSe2 nanosheets supported on graphene, where the chemical coupling effect is formed between graphene and SnSe2, working as a cushion to buffer the volume change of electrodes. The 2D/2D SnSe2/graphene heterostructure has a reversible capacity of 490.9 mAh g−1 at a current rate of 0.1C, with an ultra-long cycling stability with capacity retention of 59.3% after 1500 cycles at 0.5C, and can well work at temperatures from −30 to 70 °C. Ex situ X-ray diffraction reveals that the long-term capacity is ascribed to reversible reaction of generating LixSn with Sn and Li, and the capacity loss is attributed to the irreversible reaction with the appearance of Li2Se. The remarkable electrochemical performances, such as high specific capacity, acceptable rate feature, ultra-long cycling life, and wide temperature operation, make the SnSe2/grapheme heterostructure very potential for all-climate LIBs.

A novel strategy of utilizing eggshell wastes to condition food wastes (FW) anaerobic fermentation for efficient volatile fatty acids (VFAs) production was proposed. The VFAs production, especially acetic and butyric acids, was significantly accelerated and enhanced by eggshell conditioning. The enhanced effects were dose-dependent and improved by approximate 13-folds with optimal dose when compared with that in control. Eggshell conditioning synchronously enhanced the FW solubilization, hydrolysis and acidification steps, resulting in high VFAs production. Further analysis found that the environmental conditions (i.e., pH, ORP, trace elements, etc.) were significantly improved by eggshell conditioning. Hence, the microbial activities (i.e., hydrolases, acidogenic enzymes and ATP) and functional fermentative bacteria related with VFAs generation were enhanced and enriched. The massive accumulation of H2 and CO2 in eggshell conditioning reactors stimulated the homoacetogenesis, which also contributed to the VFAs promotion. Metatranscriptomic analysis indicated that 3 carbohydrate-active enzymes (Glycoside hydrolases, carbohydrate esterases and carbohydrate binding modules), which participate in carbohydrates and energy metabolisms, were improved. Moreover, 10 kinds of synthetase, hydrolase and oxidoreductase genes, and 4 kinds of acetyl-CoA carboxylase genes that distributed throughout the fatty acid biosynthesis pathway (especially the acetic and butyric acids generation) were all enhanced. It was the highly expressed genes and metabolic enzymes that contributed to high microbial activities and subsequent efficient VFAs production in eggshell conditioning reactors. Besides, the improvement of dewaterability and phosphorus fixation in fermentation residues further increased the added-value of conditioning FW fermentation by eggshell wastes.

Despite the fulfilling progress in fabricating metal chalcogenides-based battery electrodes, most effort focuses on construction of hybrid architectures and/or foreign elemental doping for improving electrochemical performance. In this work, we report a self-template strategy to synthesize hexagonal SnS2 and orthorhombic SnS nanoplates with abundant S vacancies as advanced anode materials of lithium-ion batteries (LIBs). Phase evolution from hexagonal SnS2 to orthorhombic SnS by thermal annealing is investigated. The resultant tin sulfide nanoplates featuring abundant S vacancies and decreased bandgaps can provide more active sites, higher Li+-ion diffusion mobility and better electronic conductivity, which are beneficial for improving electrochemical reaction kinetics. Consequently, both the S-vacancy-rich SnS2 (SVR-SnS2) and the SVR-SnS nanoplates show significantly enhanced cycling performance and rate capability compared with the interlayer-expanded SnS2 (IE-SnS2) nanoplates. Remarkably, the SVR-SnS nanoplates can exhibit outstanding rate capability (510 mAh g−1 at 10 A g−1) and excellent long-term cycling performance. A reversible capacity as high as 765 mAh g−1 at a high current of 2 A g−1 can be delivered even after 1200 cycles. It is the best cycling performance of SnS-based electrodes for LIBs to date. Besides the benefits from S vacancies, the pseudocapacitive contribution is also responsible for the fast and stable lithium storage capability. The present work provides a new strategy for modulating 2D layered tin sulfide nanoplates as promising anode materials for LIB applications.

With the increasingly serious environmental pollution and energy issues, water-based lubricating materials will gradually replace oil-based lubricating materials in some specific applications, which has become a trend. As a water-soluble lubricating additive, the synthesized proton-type ionic liquids (PILs) have the advantages of simple synthesis, good solubility stability, and excellent corrosion resistance properties, providing a method to better solve the problems of traditional water-based additives. The physical-chemical properties and lubrication functions of additives were characterized by foam corrosion test and tribological trials, with the detailed exploration of their lubricating mechanism obtained from QCM, TEM, TOF-SIMS, XPS and MD analysis. The results show that PILs display excellent friction-reducing and anti-wear performances, and improve the carrying capacity for water, which is mainly attributed to the formed tribofilm on the friction surface. The tribofilm is probably triggered by ions pair adsorption on the substrate surfaces, equipping with a typical bilayer structure self-assembly between two convexs. When it worked on the interface, a double layer structure is formed by the way of self-assembly, resulting in the formation of a continuous boundary protective film induced by tribochemical reaction, which can effectively reduce the shear damping during friction. Torque testing system results show that PILs have the smaller torque values, indicating their better lubricating performance in the small-scale platform test, which can make it to be used as a potential additive with excellent properties in water-based cutting fluids.

A heat transfer enhancement technique based on longitudinal vortex generators (LVGs) has been well established for large-scale heat exchangers. Motivated by the success of the LVGs, this paper is intended as an investigation of micromixers based on the T-shaped channel with rectangular winglet pairs (RWPs) mounted on the bottom of the main channel. The RWPs stay with an angle of attack to the main flow direction and generate longitudinal vortices to enhance fluid mixing. The effects of geometrical parameters on the performance of micromixers with micro-scale LVGs are investigated by numerical simulations and the Taguchi method. The validity of numerical simulations is examined by comparing the numerical and experimental results. The results obtained for a wide range of Reynolds numbers show that the mixing efficiency of the micromixer with divergent RWPs is greater than that of the micromixer without RWPs for convection-dominant cases as well as diffusion-dominant cases. A static Taguchi analysis shows that the relative effectiveness of the geometrical parameters can be ranked as: asymmetry index > angle of attack > winglet height > winglet spacing. Based on the relative influence of the geometric parameters, we can obtain an optimal parameter group on the parameter selected range.

An effective planar micromixer based on a meandering microchannel with converging–diverging cross section is proposed, fabricated and investigated in this work. The side walls of the microchannel consist of successive semi-elliptical surfaces with perpendicular major axes. The results of this work show that the fluid mixing in such a microchannel is enhanced by the multidirectional vortices, including the Dean vortices in the transverse plane due to centrifugal force in the meander-channel flow and the separation vortices caused by the converging–diverging cross section of the meandering channel for the case with a large flow rate and a small enough radius of curvature. We fabricate the micromixer by a single lithography process and the fluid mixing in the micromixer is observed by using a confocal spectral microscope imaging system. The fluid mixing is also simulated by a commercial code. The simulation results are in reasonable agreement with the experimental results. The results show that the mixing efficiency of the present micromixer with a large expansion ratio defined as the maximum width divided by the minimum width of the main channel is generally better than that of the ordinary meander-channel micromixer with constant cross section for the case with a large flow rate and a small radius of curvature. Besides, more simulation results show that the present meandering-channel micromixer formed by semi-elliptical side walls with perpendicular major axes is superior to the meandering-channel micromixer formed by semi-elliptical side walls with aligned major axes, the meandering-S micromixer and the Sigma micromixer.