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The adsorption technology has been widely applied in water remediation for contamination removal of dyes and bacteria, by virtue of the advantages of adsorption technology including high efficiency, energy conservation and ease of operation. Simultaneous removal of dyes and bacteria has been realized by some reported materials, but to achieve satisfactory adsorption amounts and rates remain an unmet goal for decades. Herein, a poly(methacrylatoethyl trimethyl ammonium chloride-co-methyl methacrylate) copolymer was synthesized, and then blended with polyethersulfone for the fabrication of nanofibrous membranes via electrospinning for the use of fast and massive removal of dyes and bacteria. Owing to the introduction of abundant quaternary ammonium groups, the maximum adsorption amount for methyl orange was up to 909.8 mg g−1. In addition, the modified nanofibrous membranes showed good recyclability, broad applications in severe environments, selective adsorption ability, and excellent dynamic removal performance. Especially, thanks to the abundant functional groups, the membranes showed fast adsorption ability for bacteria through electrostatic interaction. It should be noted that the clearance ratio for Staphylococcus aureus or Escherichia coli by 6 min of static adsorption could reach 93 % or 90 % for each. Additionally, dynamic removal ratio via filtration with the nanofibrous membranes could reach 99.7 % for Staphylococcus aureus or 98.7 % for Escherichia coli in 90 s. Therefore, the proposed approach towards the quaternary ammonium modified polyethersulfone nanofibrous membranes creates a new route for ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria in water remediation.

Free radical polymerization is a mature method and can be used for preparing multifunctional hydrogels by simply changing the commercial monomers, but the harsh and time-consuming initiation conditions restrict its injectable ability, which further limits its application in the biomedical field. Though some catalysts can be used to accelerate the polymerization, their application is restrained by the biotoxicity. Hence, finding a biocompatible catalyzer for in situ free radical polymerization of hydrogels has a great prospect in biomedical application but is still challenging. In this study, we discovered that silver ions could catalyze free radical polymerization under ambient by transforming hydrone into hydroxyl radicals in the presence of ammonium persulfate, and the in situ-formed hydrogels prepared by this way showed great histocompatibility, hemocompatibility, cytocompatibility, and immunocompatibility. Benefitting from its convenience and biocompatibility, the in situ polymerization of polyacrylamide-based hydrogels for tissue adhesion, wound dressing, and conductive materials on the skin could be realized by simply blending diverse ingredients. Furthermore, this discovery may be a step toward the in situ-polymerized hydrogels for biomedical applications.

Recent emerged metal-organic frameworks (MOFs), as superior drug carriers, provide novel strategies to combat pathogenic bacterial infections. Although various antibacterial metal ions can be easily introduced in MOFs for chemical bacterial ablation, such a single-model bactericidal method suffers from high-dose use, limited antibacterial efficiency, and slow sterilization rate. Hence, developing a dual bactericidal system is urgently required. Herein, we report an MOF/Ag-derived nanocomposite with efficient metal-ion-releasing capability and robust photo-to-thermal conversion effect for synergistic sterilization. The MOF-derived nanocarbon consisting of metallic zinc and a graphitic-like carbon framework is first synthesized, and then Ag nanoparticles (AgNPs) are evenly introduced via the displacement reaction between Zn and Ag+. Upon near-infrared irradiation, the fabricated nanoagents can generate massive heat to destroy bacterial membranes. Meanwhile, abundant Zn2+ and Ag+ ions are released to make chemical damage to bacterial intracellular substances. Systematic antibacterial experiments reveal that such dual-antibacterial effort can endow the nanoagents with nearly 100% bactericidal ratio for highly concentrated bacteria at a very low dosage (0.16 mg/mL). Furthermore, the nanoagents exhibit less cytotoxicity, which provides potential possibilities for the applications in the biological field. In vivo assessment indicates that the nanocomposites can realize rapid and safe wound sterilization and are expected to be an alternative to antibiotics. Overall, we present an easily fabricated structure-engineered nanocomposite with chemical and photothermal effects for broad-spectrum bacterial sterilization.

The surface of solid substrates is the main part that interacts with the environment. Therefore, surface manipulation is a key approach to improve the interaction of solid materials with their surroundings. Grafting of polymeric hydrogels is one of the major strategies for the surface modification of solid substrates. Hydrogels are the most interesting group of soft materials with numerous applications which have been studied extensively over the past few decades. In this review, we discuss the different radical polymerization strategies used for grafting hydrogel layers on the surface of flat substrates. These strategies include the thermal/redox radical polymerizations, controlled radical polymerizations, and photopolymerizations. The main factors in each approach for controlling the properties and architecture of the tethered hydrogel layer are discussed in detail along with representative examples. The soft and hydrophilic nature of the grafted hydrogel layer along with engineering of the hydrogel functional groups endows a variety of properties to the substrates including anti-fouling, anti-fogging, antibacterial, and anti-coagulation.

Although many methods have been investigated to enhance the anti-fouling and hemocompatility of polymeric membranes, developing simplified and high-efficiency strategies to synthesize low-fouling and hemocompatible membranes for safe blood purification remains a huge challenge. Herein, we proposed a facile and straightforward approach to solve the aforementioned problems. Firstly, poly (glycidyl methacrylate) (PGMA) was incorporated into polyethersulfone (PES) membranes via a combination of an in-situ crosslinking polymerization and the phase inversion method. Then, poly (acrylic acid-co-2-acrylanmido-2- methylpropanesulfonic acid) (PAA-AMPS) was covalently coated onto the PES membrane surfaces via an in-situ ring-opening reaction between the PAA and PGMA by simply immersing the membranes into the PAA-AMPS solution. Compared to pristine PES membrane, the protein adsorption amount of the modified membranes reduced; the flux recovery ratio and the resistance to blood cell and bacteria adhesion significantly increased. In addition, the hemocompatibility of the modified membranes was significantly improved, as indicated by the prolongation of the activated partial thromboplastin time and thrombin time of PES-based membranes by 157% and 584% respectively. The proposed simple and high-efficient strategy in this study might be a powerful tool to fabricate polymeric membranes with various and desired functions.

Currently, abundant efforts have been devoted to research on graphene in interdisciplinary applications due to their unique physicochemical, electronic and biological properties. Accompanying the rapid developments of graphene, it is highly important to explore graphene based bio-functional nanostructures (G-BFNs) to bridge the gap between the fundamental advantages of graphene and the requirements in designing hybridized biomaterials. Here, this review aims to outline and summarize the recent advancements in fabricating G-BFNs for advanced biological and cellular interfaces. We first discuss the general protocols for the synthesis of G-BFNs, especially diverse facile and eco-friendly strategies. Then, we carefully summarize the current developed G-BFNs based on their nanostructures and biofunctionalities, such as physiologically-stability, stimuli-responsibility, graphene-inorganic nanohybrids, functional nano-inks, nacre-like layered composites, macroporous scaffolds, 3D printed microlattices, and injectable hydrogels. Moreover, biointeractions at the interfaces of G-BFNs with viruses, bacteria and stem cells, and the relevant biocompatibilities are also highlighted. Furthermore, the emerging applications and future perspectives of G-BFNs in nanotherapeutics, anti-pathogens, tissue regeneration, and monitoring biosensors are carefully discussed. We envision that such a timely and cutting-edge review will not only take a step towards the development of G-BFNs but also inspire new opportunities by using emerged nanomaterials for biological and cellular interfaces.

In the present study, we firstly reported a green approach to prepare synthetic polymer-based particle adsorbents in aqueous solution. A novel spherical hydrogel capsule (SHC) was prepared through a facile method by partial ionic-crosslinking of carboxylated chitosan (CCS). Then, 2-acrylamido-2-methyl-propanesulfonic acid (AMPS) and acrylic acid (AA) were chosen as monomers to prepare P(AMPS-co-AA) hydrogel particles by using the SHCs as sacrificial mini-reactors. Different feed monomer molar ratios of core/shell structured CCS/P(AMPS-co-AA) hydrogel particles were synthesized through free radical polymerization. After removing the shells of the core/shell particles, the obtained P(AMPS-co-AA) particles were further used as adsorbents. The maximum adsorption capacities to the metallic ions of Ni2+, Cd2+, Cu2+, and Ag+ were 171.6, 220.5, 366.0, and 668.4 mg/g, respectively. In addition, the adsorption amount towards methylene blue (MB) reached as high as 2970 mg/g, and the removal ratio to MB by the particle columns was over 92%. Furthermore, the particles showed excellent reusability. Thus, we provide a green and economical methodology for the preparation of tunable synthetic polymer-based hydrogel particles in aqueous solution that can be used as recyclable adsorbents for water remediation.

Intensive efforts have been employed in modifying biomedical membranes. Among them, blending is recognized as a simple method. However, the conventional blending materials commonly lead to an insufficient modification, which is mainly caused by the poor miscibility between the blending materials and the matrixes, the elution of the hydrophilic materials from the matrixes during the use and storage, and the insufficient surface enrichment of the blending materials. Aiming to solve the abovementioned disadvantages, we developed novel polyethersulfone/poly(acrylic acid-co-N-vinyl-2-pyrrolidone) networked submicrogels (PES/P(AA-VP) NSs), which were blended with PES to enhance the antifouling properties, antibacterial adhesion and haemocompatible properties of PES membranes. As results, the PES/P(AA-VP) NSs showed good miscibility with the PES matrix, and hydrophilic submicrogels would enrich onto the membrane surface during the phase inversion process due to the surface segregation. The entanglement between the PES matrix and the networked submicrogels would effectively limit the elution of the submicrogels. In conclusion, the modified PES membranes prepared by blending with the PES/P(AA-VP) NSs might draw great attention for the application in haemodialysis fields.

We report a convenient, highly efficient, and universal approach for blood-compatible modification of polymer membrane based on the SI-eATRP, RAFT, and self-assembly of N-tert-butyl amide and β-cyclodextrin existed in macromolecules chains. The functional membrane surfaces with any polymer chains of hydrophilic, ionic polymer, and polysaccharide segments, for example, the copolymers of N-vinyl pyrrolidone, sodium p-styrenesulfonate hydrate, and glucose allyl amide, are easily designed and fabricated; and the thickness of polymer brushes are efficiently controlled by polymerization conditions like monomer concentration and initiator amount. As a key bio-plastic, the modified polyethersulfone membrane shows suppressed platelet adhesion, significant decreases in thrombin-antithrombin generation, and the complement activations on C3a and C5a levels compared with pristine polyethersulfone membrane; while the platelet activation (PF4) decreased. Due to the similar groups as heparin-like structure, the modified membrane effectively prolonged the activated partial thromboplastin time, thrombin time, and prothrombin time. The water contact angle of the modified membrane decreases from 89.2 to 22.3°, and the cytocompatibility of the modified membranes largely enhanced. It could be concluded that the new approach could be widely used for polymer membrane modification, and the mimic heparin-like surface seems to be a promising structure to improve the biocompatibility for blood purification application.

Polyacrylic acid/polyethersulfone (PAA/PES) capsules were adopted as templates to synthesize PAA/PES core–shell spheres, and the PES shell of spheres could be removed automatically by the swelling nature of the cross-linked PAA hydrogel core. By using the method, PAA hydrogel spheres were prepared with an ultrahigh ion exchange capacity of 12 meq g−1, and the spheres showed a high adsorption capacity for methylene blue. The PAA-polyacrylamide hydrogel spheres with dual adsorption ability and good mechanical property were also prepared. It was revealed that these two hydrogel spheres can be effectively utilized in the removal of environmental toxins.

The accumulation of low-density lipoprotein (LDL) in vascellum has been generally deemed to be a chief risk factor for the emergence of atherosclerotic cardiovascular disease (ACD), and until now, efficient and selective LDL removal has been a challenge in the clinical context. As one sort of sulfonated biomacromolecule, chondroitin presents a promising capability of cleaning LDL in the blood. However, its physiological functions normally have been restricted by its intrinsic nature, such as the inhomogeneity and uncontrollable sulfonate degree in structural characteristics. In this work, azide terminated chondroitin-analogue polymers with tunable sulfonate degrees and alkynyl modified magnetic nanoparticles (MNPs) were synthesized, respectively. Magnetic nano-adsorbents were sequentially fabricated through the azide–alkyne click reaction. Decoration of magnetic nanoparticles with functional polymers was confirmed by Fourier Transform Infrared spectroscopy (FT-IR), zeta potential measurement and transition electron microscopy (TEM). The LDL adsorption behaviours of modified magnetic nano-adsorbents presented significant variation due to the different saccharide and sulfonate ratios in the polymer chains, indicating the key roles of each pendant in the interaction with LDL molecules. Therefore, MNPs decorated with almost equal moles of saccharide and sulfonate units in polymer chains exhibited a higher affinity to LDL than the others. Due to its excellent magnetic response, the prepared nano-adsorbent realized the recyclability after a facile separation and elution process. Recycling and BSA adsorption experiments demonstrated the stable adsorption efficiency and selectivity for LDL, suggesting that the magnetic nano-adsorbent can act as an admirable material for LDL removal in potential clinical applications.

Ion exchange materials show great advantages in water purification, food industry, pharmaceutical industry, etc. However, the ion exchange capacities of ion exchange materials, especially for anion-exchange materials, at present are still relatively low. Hydrogels own abundant functional groups and show high hydrophilicity, and thus are recognized as high-potential ion exchange materials, but may deform and even crush in use due to their low mechanical strength and unavoidable swelling behavior. In this study, inspired by the root-soil structure, novel poly(methacryloxyethyltrimethyl ammonium chloride) composite hydrogel microspheres with ultrahigh ion exchange capacity (more than 3.8 meuqiv/g), low swelling ratio (less than 1.5 g/g under pH = 7), and ultrahigh mechanical strength (more than 28.1 MPa) were prepared. The microspheres showed efficient adsorption for anionic dyes (1491 mg/g for methyl orange, 1693 mg/g for Congo red, and 204.7 mg/g for amaranth, respectively) and great adsorption for bilirubin (131.6 mg/g). Taken together, the hydrogel microspheres were qualified as stable and high-efficiency ion exchange materials. More importantly, the root-soil structure opens up avenues for enhancing the dimensional stability of functional hydrogels.

Multifunctional hydrogels acting as wound dressing have received extensive attention in soft tissue repair; however, it is still a challenge to develop a non-antibiotic-dependent antibacterial hydrogel that has tunable adhesion and deformation to achieve on-demand removal. Herein, an asymmetric adhesive hydrogel with near-infrared (NIR)-triggered tunable adhesion, self-deformation, and bacterial eradication is designed. The hydrogel is prepared by the crosslinking polymerization of N-isopropylacrylamide and acrylic acid, during the sedimentation of conductive PPy-PDA nanoparticles based on the polymerization of pyrrole (Py) and dopamine (DA). Due to the conversion capacity from NIR light into heat for PPy-PDA NPs, the formed temperature-sensitive hydrogel exhibits tissue adhesive as well as NIR-triggered tunable adhesion and self-deformation property, which can achieve an on-demand dressing refreshing. Systematically in vitro/in vivo antibacterial experiments indicate that the hydrogel shows excellent disinfection capability to both Gram-negative and Gram-positive bacteria. The in vivo experiments in a full-layer cutaneous wound model demonstrate that the hydrogel has a good treatment effect to promote wound healing. Overall, the asymmetric hydrogel with tunable adhesion, self-deformation, conductive, and photothermal antibacterial activity may be a promising candidate to fulfill the functions of adhesion on skin tissue, easy removing on-demand, and accelerating the wound healing process.

Owing to the insufficient guidance of new bone formation in orthopedic and craniomaxillofacial surgery, construction of a guided bone regeneration membrane to support vascularized bone regeneration remains a challenge. Herein, an electrospun asymmetric double-layer polycaprolactone/collagen (PCL/Col) membrane modified by metal-organic framework (MOF) crystals is developed. The optimization of the PCL/Col weight ratio (1:1 and 1:1.5) enables the composite membrane with a balanced tensile strength (only fell by 49.9% in wet conditions) and a controlled degradation rate (completely degraded at 12 weeks). The MOF crystals can provide a pH-responsive release of Zn2+ ions. In vitro experiments indicate that the barrier layer functions to prevent the infiltration of fibrous connective tissue. The MOF crystal layer functions to enhance osteogenesis and angiogenesis in vitro. Using a rat calvarial defect model, the MOF crystals exhibit a sign of osteoinductivity along with blood vessel formation after 8 weeks post-surgery. Strikingly, when assessed in a chick chorioallantoic membrane model, the MOF modified membrane demonstrates a significant angiogenic response, which can be envisaged as its outstanding merits over the commercially Col membrane. Therefore, the MOF crystals represent an exciting biomaterial option, with neovascularization capacity for bone tissue engineering and regenerative medicine.

An in situ strategy was introduced for synthesizing carbon modified graphitic carbon nitride(g-C3N4) by using urea/4-aminobenzoic acid(PABA) co-crystal(PABA@Urea) as precursor materials. Via co-calcination of the PABA co-former and the urea in PABA@Urea co-crystals, C guest species were generated and compounded into g-C3N4 matrix in situ by replacing the lattice N of the carbon nitride and forming carbon dots onto its layer surface. The carbon modification dramatically enhanced visible-light harvesting and charge carrier separation. Therefore, visible light photo-catalytic oxidation of methylene blue(MB) pollution in water over the carbon modified g-C3N4 (C/g-C3N4) was notably improved. Up to 99% of methylene blue(MB) was eliminated within 60 min by the optimal sample prepared from the PABA@Urea co-crystal with a PABA content of 0.1%(mass ratio), faster than the degradation rate over bare g-C3N4. The present study demonstrates a new way to boost up the photocatalysis performance of g-C3N4, which holds great potential concerning the degradation of organic dyes from water.

Cells reside in a dynamic microenvironment in which adhesive ligand availability, density, and diffusivity are key factors regulating cellular behavior. Here, the cellular response to integrin-binding ligand dynamics by directly controlling ligand diffusivity via tunable ligand-surface interactions is investigated. Interestingly, cell spread on the surfaces with fast ligand diffusion is independent of myosin-based force generation. Fast ligand diffusion enhances α5β1 but not αvβ3 integrin activation and initiates Rac and RhoA but not ROCK signaling, resulting in lamellipodium-based fast cell spreading. Meanwhile, on surfaces with immobile ligands, αvβ3 and α5β1 integrins synergistically initiate intracellular-force-based canonical mechanotransduction pathways to enhance cell adhesion and osteogenic differentiation of stem cells. These results indicate the presence of heretofore-unrecognized pathways, distinct from canonical actomyosin-driven mechanisms, that are capable of promoting cell adhesion.

Excessive bilirubin in the body of patient with liver dysfunction or metabolic obstruction may cause jaundice with irreversible brain damage, and new type of adsorbent for bilirubin is under frequent investigation. Herein, graphene oxide based core @ polyethersulfone-based shell beads are fabricated by phase inversion method, amides and heparin-like polymer are introduced to functionalize the core-shell beads. The beads are successfully prepared with obvious core-shell structure, adequate thermostability and porous shell. Clotting times and protein adsorption are investigated to inspect the hemocompatibility property of the beads. The adsorption of bilirubin is systematically investigated by evaluating the effects of contacting time, initial concentration and temperature on the adsorption, which exhibits improved bilirubin adsorption amount for the beads with amides contained cores or/and shells. It is worth believing that the amides and heparin-like polymer co-functionalized core-shell beads may be utilized in the field of hemoperfusion for bilirubin adsorption.

Bacterial attachment and the subsequent colonization on the surfaces of bio-materials usually result in biofilm formation, and thus lead to implant failure, inflammation and so on. Herein, a novel mussel-inspired antibacterial and antifouling membrane was designed via co-deposition of polydopamine (PDA) and a zwitterionic polymer, followed by incorporating bactericidal silver nanoparticles (Ag NPs). Polyethyleneimine-graft-sulfobetaine methacrylate (PEI-SBMA) was firstly co-deposited onto a polyethersulfone (PES) membrane surface via crosslinking with PDA to construct an antifouling surface. Then, Ag NPs were in situ synthesized on the membrane surface without adding any external reducing agents. Elemental and morphological surface analyses confirmed the successful co-deposition of PEI-SBMA onto the PES surface and the successful reduction of silver ions by the PDA layer. In addition, the PEI-SBMA could significantly reduce Ag NP aggregation, and the modified surface exhibited sustained bactericidal activity and effective inhibition of bacterial adhesion. This demonstrated that the proposed approach was straightforward to fabricate mussel-inspired antifouling and antibacterial membranes, which showed great potential to be used in biomedical fields.

A new class of hydrogels distinguished by electro-conductivity and high hemo-compatibility, which resemble biological tissues, are promising candidates for a plethora of biomedical applications. This work describes the design of highly elastic and biocompatible hydrogels using polypyrrole (PPy) as the conductivity media. The bio-inspired design of heparin-mimicking sodium alginate (HMSA) combined with tough alginate/polyacrylamide (PAM) is selected to form chemical and physical cross-linked binary hydrogel networks, while the incorporation of interfacial polymerized PPy endows the hydrogels with electro-conductivity. The resulting hydrogels exhibit a mesh-like hierarchical structure with excellent mechanical strength; moreover, the hydrogels show greatly enhanced electro-conductivity (up to 0.63 S m−1). In addition, due to the presence of the unique heparin-mimicking structure, the hydrogels possess a desirable anticoagulant ability and biocompatibility demonstrated via antithrombotic evaluations together with cell culture observations. The facile synthesis of HMSA/PAM/PPy hydrogels and their robust physical, chemical and biological performance make them attractive components for the future generation of biosensors and bioelectrodes.

Current therapy for liver failure and concomitant hyperbilirubinemia faces the challenge of poor hemocompatibility and bleeding risks associated with the anticoagulant injection. Herein, heparin-mimetic biomacromolecule (HepMBm) with a similar degree of sulfation and anticoagulant properties to heparin was synthesized by imitating the structure of natural biomacromolecule heparin. Then HepMBm was used to prepare nanocomposite spheres based on reduced graphene oxide (rGO). The formation of a dual-network structure in the spheres endowed the spheres with improved dimensional stability. The proposed spheres exhibited outstanding blood compatibilities and excellent self-anticoagulant properties. The bilirubin adsorption experiments and whole blood bilirubin removal assay indicated that the spheres exhibited high bilirubin removal capability from whole blood (The removal ratio was 99.69%.). The spheres open new routes for a therapeutic strategy without a plasma separation system and heparin pump, which may be a step toward a lightweight wearable artificial liver.

The aim of this study was to fabricate a novel bilayered wound dressing with excellent antibacterial performance through electrospinning and in situ cross-linking polymerization. Quaternary ammoniu...

We demonstrate highly efficient white quantum dot light emitting diode (QLED) devices using three separate quantum dots emission layers. The three luminescent layers are separated by two poly(p-phenylene benzobisoxazole) precursor buffer layers. These organic buffer layers have high lowest unoccupied molecular orbital levels, which contributes to the blocking of extra electrons and the balance of hole and electron injection. The developed trilayered white QLED device with organic buffer exhibits a high external quantum efficiency of 9.6 %, 16.4 cd/A in current efficiency, and a bright luminance of 4245.3 cd/m2.

In this study, poly(ionic liquids/ N-isopropylacrylamide) (PIL/NIPAM) modified poly(ether sulfone) microporous membranes were prepared using a pore-filling method. Due to the anion-sensitive wettability of the PIL and the thermal-sensitive phase transformation of PNIPAM, the permeability of the modified membranes showed robust anion and thermal dual-responsive behaviors. In addition, the response temperature of the membranes could be adjusted precisely from 30 to 55 °C by anion exchange, which was attributed to the cooperative interaction of the PIL and PNIPAM. The switchable response temperature and the dual-responsive performances of the membranes were demonstrated by measuring the water fluxes under various conditions. The results indicated that the membrane permeabilities increased when exchanging the counteranions (CAs) from hydrophilic to hydrophobic ones; the thermal response behaviors were also obvious, and the sensitivity increased when increasing the hydrophobicity of the CA (the fluxes could be adjusted from 0 to 3800 mL/m

Pathogen capture and removal from whole blood is a new strategy for extracorporeal blood purification, especially in initial treatment of sepsis before pathogen identification. Herein, hemocompatible magnetic particles with broad-spectrum bacteria capture capability were proposed for pathogen removal from whole blood, omitting the necessity of pathogen identification. Firstly, we designed and synthesized a new kind of imidazolium-based ionic liquid with good antibacterial activity, and polydopamine coating was utilized as a hemocompatible platform to immobilize ionic liquids on Fe3O4 nanoparticles, forming the hemocompatible magnetic particles (Fe3O4@PDA-IL). The magnetic particles exhibited good hemocompatibility and performed well in the removal of various species of clinically significant pathogens from human whole blood, including S. aureus, E. coli, and the hard-to-treat bacteria of P. aeruginosa and Methicillin-resistant S. aureus, which are the most common pathogens in bloodstream infections. Besides, the Fe3O4@PDA-IL particles were also capable to remove bacterial endotoxins from blood, inhibiting further aggravation of sepsis. Overall, we demonstrated the application of hemocompatible magnetic particles in the removal of pathogens and bacterial endotoxins from whole blood via electrostatic and hydrophobic interactions, without significant effects on blood cells or the activation of coagulation and complement, addressing the feasibility of using imidazolium-based ionic liquids for bacteria capture and removal from whole blood. It would contribute to the development of magnetic separation-based approaches to remove bacteria and bacterial endotoxin for extracorporeal blood purification, especially in initial sepsis therapy before pathogen identification.

Solution pH is an important factor in the adsorptive behavior of ionizable dyes in the chemical and biotechnology industries. In this study, novel pH-responsive zwitterionic hydrogels were prepared by the copolymerization of acrylic acid and methylacryloyloxyethyl trimethylammonium chloride. The results indicated that the hydrogels showed bidirectionally pH-responsive behaviors: the swelling ratio was small in neutral pH value and increased with the increase or decrease of pH values. Meanwhile, the selective adsorption capacities of the hydrogels for anionic or cationic dyes could be controlled by adjusting the pH values. The hydrogels might be applied in many fields, such as adsorption and separation and water treatment.

Sodium alginate (SA) beads with ultrahigh adsorption capacity were prepared via hydrogen bonds between SA and 2-acrylamido-2-methylpropa-1-propanesulfonic acid (AMPS), and the AMPS was then post-cross-linked to manufacture SA/PAMPS beads. The equilibrium adsorption capacities of methylene blue (MB) and Pb2+ for the SA/PAMPS10 beads were 2977 and 2042 mg/g, respectively. Although the SA beads exhibited higher equilibrium adsorption capacities of MB and Pb2+ than those of the SA/PAMPS10 beads, the SA/PAMPS10 beads had better mechanical property and higher stability. The pseudo-second-order kinetic model and the Langmuir isotherm described the adsorption processes of the SA/PAMPS10 beads for MB well. In addition, the SA/PAMPS10 beads could be reused with stable adsorption capacity for at least three cycles. The beads also had excellent performances on absorbing methylene violet and other heavy metal ions (Cu2+, Cd2+ and Ni2+). Therefore, the SA-based beads with high adsorption capacity might be good candidates for industrial pollutant treatments.

Oxidative desulfurization is considered to be one of the promising new methods for super-deep desulfurization of fuel oil. Herein, zinc phthalocyanine/g-C3N4 (g-C3N4/ZnTcPc) composites were synthesized by a facile in situ hydrothermal technique, utilizing g-C3N4, Zn(CH3COO)2 and 1,2,4-benzenetricarboxylic anhydride as the precursors. The crystal structure, morphology and chemical environment of the catalysts were respectively confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Photocatalytic activity of the resulting g-C3N4/ZnTcPc composites was evaluated by desulfurization of thiophene in fuel under visible light with molecular O2 as the oxidant. Compared with pure g-C3N4 and ZnTcPc, g-C3N4/ZnTcPc presented a significantly enhanced photocatalytic activity for the degradation of thiophene in fuel under visible irradiation. Sulfur content of model gasoline (800 ppm) after desulfurization for 90 min was decreased to 125 ppm. The possible preparation pathway of g-C3N4/ZnTcPc has been proposed according to the results of XRD and TEM. The formation mechanism of g-C3N4/ZnTcPc–O2 complex is proposed to be desulfurization by molecular oxygen.

Functional hydrogels own superior advantages in wastewater purification thanks to their abundant functional groups and porous structure. However, the hydrogels cannot be used as stable adsorbents due to their insufficient mechanical properties and exorbitant swelling ratio. Inspired by the strong mechanical properties of the reinforced-concrete structure, the novel reinforced-concrete structured hydrogel microspheres were prepared, and the structure endowed the hydrogel with superior mechanical properties (the compressive stress was 27.4 MPa with a strain of 80%) and restricted swelling ratio (the water uptake was less than 2.2 g/g under pH = 7) but caused no obviously negative effect on the originally outstanding adsorption ability. The adsorption column filled with the concrete-structured hydrogel microspheres reached stable and efficient removal of the cationic dyes and heavy metal salts (1246 mg/g for MB, 491 mg/g for MV, 1253 mg/g for Cu(II), 564 mg/g for Ni(II), 640 mg/g for Cd(II), and 252 mg/g for...

A facile and versatile strategy towards antifouling surfaces is an emerging area of huge potential and with an increasing scientific interest. Herein, a universal approach for fabricating antifouling surfaces was developed based on tannic acid (TA) and a novel reactive zwitterionic polymer. Firstly, a thin layer was formed on polyethersulfone (PES) membranes surface with TA molecules via multivalent anchoring sites in few minutes. Subsequently, a reactive zwitterionic polymer (for the first time reported based on quaternization of PEI) was post-crosslinked on the layer via a convenient dip-coating process at room temperature. The as-prepared surface exhibited excellent hydrophilicity confirmed by water contact angle, and its electrically neutral property was affirmed by zeta potential measurement. The surface displayed prominent antifouling efficacy which was evaluated by proteins adsorption, bacteria attachment and platelets adhesion. Meanwhile, after the post-crosslinking, the stability of the surface was significantly enhanced in either acidic or alkaline condition compared with original TA-coated surface. Benefiting from the universal profile, easy operation and low cost of the TA assembly process, as well as the excellent antifouling ability of the zwitterionic polymer, the proposed strategy provided a universal route in design of antifouling surfaces used in biomedical fields.

The currently used hemoperfusion adsorbents such as activated carbon and ion-exchange resin show dissatisfactory hemocompatibility, and a large dose of injected heparin leads to the increasing cost and the risk of systematic bleeding. Natural polysaccharide adsorbents commonly have good biocompatibility, but their application is restricted by the poor mechanical strength and low content of functional groups. Herein, we developed an efficient, self-anticoagulant and blood compatible hemoperfusion adsorbent by imitating the structure and functional groups of heparin. Carrageenan and poly(acrylic acid) (PAA) cross-linked networks were built up by the combination of phase inversion of carrageenan and post-cross-linking of AA, and the formed dual-network structure endowed the beads with improved mechanical properties and controlled swelling ratios. The beads exhibited low protein adsorption amounts, low hemolysis ratios, low cytotoxicity, and suppressed complement activation and contact activation levels. Especially, the activated partial thromboplastin time, prothrombin time, and thrombin time of the gel beads were prolonged over 13, 18, and 4 times than those of the control. The self-anticoagulant and biocompatible beads showed good adsorption capacities toward exogenous toxins (560.34 mg/g for heavy metal ions) and endogenous toxins (14.83 mg/g for creatinine, 228.16 mg/g for bilirubin, and 18.15 mg/g for low density lipoprotein (LDL)), thus, highlighting their potential usage for safe and efficient blood purification.

This work describes the preparation, characterization and removal capability of a novel biomass derived carbonaceous sponges (CS) and their nanocomposites. The CS has hierarchically porous structure which is composed of lamellar structures and secondary porous structures. The pore size is on a scale from 1 nm to 200 μm. Utilizing the CS as adsorbents, rapid removal of model organic molecules, including methylene blue (MB), methyl orange (MO) and crystal violet (CV), from their aqueous solutions can be completed within 1 min with the assistance of pressure and the removal efficiency reaches up to 100%, 81% and 98%, respectively. The removal capabilities for CS towards MB, MO and CV are 0.0769 g/g, 0.2218 g/g and 1.0384 g/g, respectively and 0.0635 g/g, 0.0977 g/g and 0.8634 g/g, respectively for CS nanocomposites.

Development of antibacterial membranes is strongly desired for biomedical applications. Herein, we integrated antifouling and bactericidal properties on polymeric membrane surface via Schiff-based layer-by-layer (LbL) assembly. Zwitterionic polymers bearing plentiful amino groups (based on polyethylenimine (PEI) and sulfobetaine methacrylate (SBMA), and termed as PEI-SBMA) were utilized to prepare an antifouling membrane surface; then robust wide-spectrum bactericidal Ag nanoparticles (Ag NPs) were in situ generated on the surface. The as-prepared zwitterionic polymer surface showed excellent resistance to protein adsorption and bacterial adhesion. The Ag NPs could be tightly and uniformly distributed on the membrane surface by the chelation of PEI-SBMA, and endowed the membrane with bactericidal activity. Meanwhile, the Ag NPs loaded membrane could effectively resist bacterial attachment for a long time, even though the bactericidal activity lost. The proposed bactericidal and antifouling membrane was flexible, versatile and could be large-scale preparation; and this strategy would have great potential to be widely used to avoid undesired bacterial contamination of biomedical implants or biological devices.

Herein, a substrate-independent ultrathin hydrogel film was constructed on a microfiltration membrane through layer-by-layer (LbL) thiol-ene click chemistry to improve the antifouling and antibacterial properties. In our strategy, ene-functionalized dopamine was synthesized and coated onto a model substrate (polyethersulfone membrane) to introduce double bonds as anchoring sites for the hydrogel film; thiol-functionalized poly[oligo(ethylene glycol)mercaptosuccinate] (POEGMS) and ene-functionalized P(SBMA-co-AA) were synthesized as hydrogel precursors. The membrane was alternately immersed in the precursor solutions to form the ultrathin hydrogel film. Finally, Ag nanoparticles (AgNPs) were loaded into the hydrogel layer by adsorption and reduction procedures. By coating the hydrogel films, the loaded AgNPs could kill almost all the contacting bacteria and the bacteria in the surroundings, and the enhanced hydrophilicity of the modified membrane could effectively prevent the attachment of the bacteria. The membrane flux showed no significant decrease, the rejection ratio of BSA increased from 51% to 89%, and the FRR increased from 36% to 90%. Moreover, the improvement of the hemocompatibility was confirmed by the decline in the plasma protein adsorption, prolonged clotting times, low hemolysis ratio, and prevention of platelet adhesion. Compared with that of other techniques for attaching hydrogel films, the main advantage of the current technique is that the hydrogel film thickness could be well controlled within the nanometer range; thus, it could significantly improve the antifouling and antibacterial properties of the membrane, but without compromising its permeability. Another advantage is that it is versatile for various substrates such as PVDF, PAN, and CA. This study opens up a facile and versatile route for anchoring ultrathin hydrogel film onto polymeric membranes to achieve excellent antifouling, antibacterial and hemocompatible properties.

Flexible strain sensors are highly used in soft robotics, human–machine interfaces and health monitoring devices. However, it is still a big challenge to construct strain sensors with excellent mechanical properties and broad sensing ranges. In this study, a class of extremely stretchable and electrically conductive hydrogels with dually synergistic networks are fabricated for wearable resistive-type strain sensors. Dually synergistic networks are composed of a soft poly(acrylic acid) (PAA) network and a rigid conductive polyaniline (PANI) network. The PAA network is crosslinked by amphiphilic block copolymers, and the PANI network is chemically doped and ionically crosslinked by phytic acid and these two networks are further interlocked by physical entanglements, hydrogen bonds and ionic interactions. The resulting hydrogels have high tensile strength, controllable conductivity and large tensile deformation (1160%). Moreover, these hydrogels are utilized for fabricating strain sensors with good sensitivity and a wide sensing range (0–1130%). The high performances of hydrogels make such strain sensors suitable for wearable devices monitoring both subtle and large strains induced by human motions, including moving of two hands, bending of joints, conducting of gestures and swallowing.

The development of highly efficient adsorbents with a fast adsorption rate and high adsorption capacity presents an enticing prospect for wastewater remediation. In this paper, a novel ultrafast adsorption nanofibrous membrane (UFAM) for organic dyes was prepared through a simple functional group surface migration method. An amphiphilic copolymer of methyl methacrylate and sodium styrene sulfonate was synthesized in a mass ratio of 3 : 2 by free radical polymerization and further blended into polyethersulfone (PES) to prepare functionalized PES nanofibrous membranes by electrospinning technology. Just by soaking in water and lyophilization, the hydrophilic and negatively charged sulfonate groups migrated and concentrated on the membrane surface, and the obtained UFAM was found to be exceptionally efficient in the removal of methylene blue (MB) dye from aqueous solution. Especially, an ultrafast adsorption rate for MB with an adsorption equilibrium time of within 5 min was reported for the first time. The mechanism of the ultrafast adsorption based on the sulfonate group migration and enrichment was also especially explored in this study. In addition, the UFAM also showed excellent performance of recyclability, dynamic filtration–purification, selective adsorption for cationic dyes from mixed dye solutions and smart filtration–separation for cationic and anionic dyes. Therefore, we envision that this study will not only provide a new strategy to construct low-cost and highly efficient adsorbents, but also demonstrate their potential applications in the removal of organic dyes on a large scale.

The conventional strategies employed for introducing functional groups onto the surfaces of nanofibrous membranes (NFMs) require complicated steps. Herein, we report a simple strategy for the fabrication of negatively-charged polyethersulfone (PES) NFMs adsorbent by utilizing one-step electrospinning. Firstly, functional groups were introduced into the electrospinning solution via in-situ cross-linking co-polymerization of sodium styrene sulfonate and acrylic acid in PES solution. Then, the solution was directly used to electrospin into negatively-charged PES NFMs. Sufficient characterization methods were carried out to demonstrate the successful fabrication of the functional NFMs. Batch adsorption experiments for various kinds of dyes with different initial concentrations and pH values were carried out. The results indicated that the NFMs showed efficient adsorption capacity for cationic dye of methylene blue MB. In particular, binary dye adsorption column experiments were carried out and the membranes exhibited excellent separation efficiency of 98.29% for MB/amaranth mixture. The successful fabrication of such fascinating NFMs adsorbent by using this simple approach may provide new sights into the design and development of adsorptive materials for industrial wastewater treatment with excellent separation efficiency towards mixed dyes.

Stretchable and elastic double network (DN) hydrogels are increasingly investigated for flexible electronics but their recyclability is rarely considered. Herein, recyclable, stretchable and conductive DN-hydrogels are explored and utilized in flexible resistive-type strain sensors. Such DN-hydrogels are fully physically cross-linked and composed of a crystalline domain cross-linked poly(vinyl alcohol) (PVA) network and a Tb3+-cross-linked poly(acrylic acid sodium) (PAANa–Tb3+) network. Due to their unique structure, DN-hydrogels have excellent recyclability and flexibility, and they are also conductive and photoluminescent due to the presence of Tb3+. Utilizing DN-hydrogels, flexible strain sensors are assembled and further applied to monitor large human motions, such as moving of two hands and bending of joints, as well as subtle physiological activities including moving of the bicipital muscle, swallowing and breathing. Overall, the present example not only helps to understand the toughening and strengthening mechanism of fully physically cross-linked DN-hydrogels, but also offers a clue to develop multifunctional hydrogels for recyclable flexible electronics.

Smart materials with controllable responses to various stimulations offer considerable potential in many applications. Herein we report a simple and efficient method to fabricate ionic strength- and thermo-responsive polyethersulfone composite membranes using zwitterionic copolymers of sulfobetaine methacrylamide (SBMI) and sulfobetaine methacrylate (SBMA). The permeability of the modified membranes could be adjusted by varying the ionic strength from 0 mol kg−1 to 1.0 mol kg−1 and/or varying the surrounding temperature from 15 °C to 90 °C, and both the responses were reversible. The thermo-response transition temperature could be regulated by changing the chemical compositions of the zwitterionic copolymers. Furthermore, the zwitterionic copolymer modified membranes exhibited excellent antifouling resistances to protein solutions and surfactant-stabilized oil-in-water emulsions. Their ionic strength- and thermo-responsive flux, separation ability, and excellent antifouling properties endowed the membranes with a wide range of applications in the field of separation.

In this study, an environmentally friendly approach for surface modification of polymer membrane was reported, which named surface-initiated electrochemically mediated atom transfer radical polymerization (SI-eATRP). It was triggered after diffusion of a CuI/L activator generated at a working electrode. The introduction of electrochemically mediation can control the polymerization of monomers by a one-electron reduction of an initially added air-stable CuII salt. The reaction was carried out in an electrochemical cell with a three-electrode system at low temperature. Using this technique, hydrophilic polymer brushes of poly(N-vinylpyrrolidone) were grafted onto PES membrane surface. The effects of reaction conditions like polymerization time, monomer concentration, initiator amount, and different monomer on the polymerizations of monomer were investigated in detail. Based on these data, we concluded that the polymerization on polymer membrane surface could be controlled by mediating the reaction condition. Moreover, the precisely controlled polymerization may allow it to serve as excellent model systems for polymer membrane modification, in general, to illustrate the role of electrochemically mediating on the polymerization approach. And the water contact angle of the modified membrane decreased from 89° to 72°. The APTT of the modified membrane increased from 46 s to 81 s. Those results indicated that the surface modification by grafting PVP brushes provided practical application for the PES membranes with high surface properties.

A series of poly(ionic liquid)s (PILs) modified polyethersulfone membranes were fabricated via an in-situ cross-linking copolymerization method. Due to the positive charge and ion-exchange properties of the PILs, the membranes showed anion species and strength responsive behaviors. The morphologies and chemical compositions of the membranes were characterized by scanning electron microscope and X-ray photoelectron spectroscopy. The anion species and strength responsive properties were investigated by measuring the fluxes of the membranes with various anion species and concentrations of salt solutions. The anion strength response of the membranes was positive, and the responsive coefficient of the membranes (the ratio of the salt water flux to pure water flux) could reach 26 times when responded to the stimulus of NaCl aqueous solution; the cation species and concentrations had barely influence on the responsive behavior. Meanwhile, the membranes were responded to both anion species (including PF6−, BF4− and SCN-) and their strength: the pure water fluxes and the morphologies of the modified membranes changed associated with different types of anions, and the membranes after ion-exchanging also showed obvious anion strength responsive behaviors to the corresponding salt solutions. The facile design of anion-responsive membranes via in-situ cross-linking polymerization opens up a new route to fabricate “intelligent” membranes for ion-recognizable chemical/biomedical separations and purifications.

In this study, a novel core@shell bead adsorbent was fabricated by using poly (acrylic acid) (PAA) microgels and polyethersulfone (PES) via a facile and versatile strategy for dye uptake from wastewater. PAA microgels were synthesized by distillation precipitation polymerization, followed by enwrapping with PES films to form core@shell beads by a phase inversion technique. The scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) mapping confirmed that the bead had a core@shell structure with PAA microgels in the core and PES on the shell. Batch adsorption experiments indicated that the contact time, initial dye concentration, adsorbent dosage, pH and ionic strength greatly affected the adsorption process. The beads could adsorb methylene blue as high as 84.82 mg/g while the adsorption capacities of methyl violet, rhodamine B, amaranth red and methyl orange were 43.37, 14.60, 2.93 and 2.29 mg/g, respectively. Simultaneously, the beads were recyclable for the removal of dye and the adsorption process fitted well with the non-linear Freundlich isotherm. All the results indicated that the prepared beads were promising in dye treatment.

In this study, polyethersulfone (PES) membranes were modified by in situ cross-linking polymerization of polyurethane with functional groups of –COOH and –SO3H using PEG as the chain extender in one pot, followed with a phase inversion technique. The composite membranes were characterized by FTIR, water contact angle, and scanning electron microscope. Comparing with pristine PES membrane, the modified membranes showed decreased water contact angles and changed cross-sectional morphology. The modified membranes also showed decreased protein adsorption and suppressed platelet adhesion, as well as improved antifouling property. In addition, the composite membranes had prolonged activated partial thromboplastin times due to the functional groups and improved hydrophilicity. The results of contact activation and complement activation also indicated that the modified membranes had good blood compatibility. Furthermore, the cytocompatibility was significantly improved. The highly hemocompatible PES composite membranes fabricated by the in situ cross-linking polymerization of polyurethane may have great potential to be used in the field of blood purification.

We report on a self-defensive bilayer hydrogel coating which can switch from a cell adhesion surface to an antibacterial adhesion surface. To covalently attach the coating, an antifouling hydrogel thin film was firstly prepared on a thiol modified substrate as the bottom layer via the thiol–ene click reaction of the ene-functionalized copolymer of poly(sulfobetaine methacrylate-acrylate acid-2-hydroxyethyl methacrylate) (P(SBMA-AA-HEMA)). Thereafter, heparin-mimicking polymer chains were grafted onto the hydrogel film surface as the upper layer via surface initiated atom transfer radical polymerization. The ester group of HEMA was designed as the sensitive part which could be cleaved in a bacterial infectious environment, while the hydroxyl group was designed as the anchoring point of the upper layer. The surface morphology and chemical composition after each modification step were characterized by scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. The bilayer coating could promote cell adhesion and proliferation, as well as bacterial adhesion. After being immersed into a cholesterol esterase solution (simulative bacterial infectious environment), the upper layer could be detached rapidly, and the exposed bottom layer then showed strong resistance to bacteria. Our approach towards bacteria-responsive “intelligent” coating gives new insights into the antibacterial protection of biomedical devices.

To improve the hemocompatibility and antifouling property of polyethersulfone (PES) membranes, heparin-mimicking microgels of poly(acrylic acid-co-N-vinyl-2-pyrrolidone) (P(AA-VP)) and poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylamide) (P(AMPS-AM)) were synthesized by conventional free radical copolymerization, and then incorporated into a PES matrix by blending. The results of Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and scanning electron microscopy (SEM) confirmed that heparin-mimicking microgels were successfully synthesized. The presence of the microgels in the membrane matrix was also confirmed by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA), and SEM. Compared with pristine PES membranes, the improvement of the antifouling property of the heparin-mimicking microgel modified membranes was demonstrated by the increased flux recovery ratio and improved anti-bacterial adhesion, while the enhancement of hemocompatibility for the modified membranes was proved by the decreased plasma protein adsorption, suppressed platelet adhesion, prolonged clotting times, as well as depressed blood-related complement activation. Additionally, after introducing the heparin-mimicking microgels, the membranes showed enhanced cell adhesion and proliferation properties. These results indicated that the heparin-mimicking microgel modified membranes had great potential to be used as blood contacting materials.

Wound treatment is a long-lasting clinical issue. Poor angiogenesis leading to delayed wound closure causes huge challenges for healing. Functional electrospun membranes have been established as an efficient strategy to promote wound recovery by protecting and improving vascular regeneration. Here, we aimed to investigate the effect of tazarotene, an active drug for angiogenesis, loaded in aligned electrospun nanofibrous barrier on a soft tissue wound. This aligned membrane was arranged in a single direction, and tazarotene could be released from its nanofibers sustainably. The in vitro study demonstrated that compared with the random drug-loaded or other control groups, the aligned tazarotene-loaded membranes [poly-caprolactone (PCL)/AT] could stimulate proliferation, migration, angiogenesis, and vascular endothelial growth factor secretion and its gene expression of human umbilical vein endothelial cells. Furthermore, the in vivo model showed that the prepared tazarotene-loaded aligned membrane significantly accelerated the speed of healing, improved the neovascularization and re-epithelialization, and inhibited the inflammatory reaction in the wound area. All these results above indicated that the PCL/AT nanofibrous dressing, which could promote angiogenesis because of both stimulation of structure and chemical signals, is a promising wound-caring material.

The prevention of bacteria-induced infections has been increasing in importance in both clinical surgery and biomedical engineering. Although great attention has been paid to designing intelligent antibacterial surfaces, the fabrication processes are still not facile and universal enough, and the antibacterial efficiencies of these surfaces are also not ideal. Herein, ionic liquid (IL) molecules of 3-(12-mercaptododecyl)-1-methyl-1H-imidazol-3-ium bromide (IL(Br)) were synthesized with the minimum inhibitory concentrations as low as 4 and 8 μg mL−1 against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. By simply immersing a polymeric substrate into the IL(Br) solution, an antibacterial surface with high killing efficiency of 99% against S. aureus (94% against E. coli) was achieved via a mussel-inspired approach. Subsequently, 97% S. aureus and 95% E. coli on the substrate could be released by simple ion-exchange of Br− with (CF3SO2)2N− due to the ion sensitivity of the IL molecular brushes. Thus, the proposed facile strategy towards a superior efficiency surface could be potentially used in intelligent antibacterial fields.

Applications of effective and steady metal catalysts for the hydrogen evolution reaction (HER) via electrolysis of water have a huge potential to relax energy crisis and reduce carbon dioxide emission. Herein, we design a simple, facile, and general approach for the synthesis of a series of transition-metal phosphide nanoparticles embedded in N-doped carbon (NC) nanomaterials using metal salts, abundantly available hexamethylene diamine tetra(methyl phosphonic acid), and urea as precursors. The resultant transition-metal phosphide nanoparticles can serve as high-efficiency and steady HER catalysts. Particularly, when the current density is 10 mA cm-2, the overpotentials of the obtained RhP2@NC are 30, 85, and 70 mV in acid (0.5 M H2SO4), neutral (1 M PBS), and alkaline (1 M KOH) solutions, respectively. Besides, the RhP2@NC exhibits good stability after 10 h in aforementioned solutions. More importantly, it is suited to fabricate other transition-metal phosphide nanoparticles/NC heterostructures by this synthetic strategy. The obtained CoP@NC, FeP@NC, Ni2P@NC, and Cu3P@NC also show relatively high efficiency for HER. Hence, the versatile synthesis strategy opens a new route for the research and fabrication of transition-metal phosphide-based catalysts for HER.

Given the complexity of pollutants in wastewater, development of facile and effective multifunctional materials, which can not only kill bacteria but also remove dyes from wastewater, is in high demand. Herein, a facile strategy for the preparation of positively-charged nanofibrous membranes (NFMs) is reported via the combination of electrospinning and in-situ cross-linked polymerization of poly ([2-(methacryloyloxy)-ethyl] trimethyl ammonium chloride) (PMETAC) in poly (ether sulfone) (PES) solution. The quaternary ammonium salt polymer of PMETAC enabled the NFMs with positive charge to kill bacteria and remove anionic dyes. The antibacterial tests including agar plate counting and live/dead staining indicate that the NFMs show strong antibacterial ability with bacterial killing ratios of nearly 99% for both Escherichia coli and Staphylococcus aureus, as well as remarkable recyclability towards killing bacteria. The dyes adsorption experiments show that the NFMs exhibit high adsorption capacity for anionic dyes up to 208 mg g−1 for Congo Red (CR) and good reusability toward CR. Impressively, the membrane adsorption column test indicates that the CR dye removal ratio is up to 100% for the first time, and that is still as high as 96.5% for the third time with a fresh dye solution. Given the above advantages, such fascinating NFMs may provide new perspectives in the exploitation of multifunctional membrane materials for complex water remediation.