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Membrane active antimicrobial peptide mimics have been considered as promising alternatives to antibiotics, which interact with bacterial cell membranes to combat bacteria and avoid the emergence of multidrug-resistant bacteria. Herein, a series of star-shaped and membrane-active cationic polyetheramides derived from amino acids, were synthesized via condensation of amino acids and polyetheamine (T403). The antibacterial and anti-biofilm activitives as well as the biocompatibility of these amino acids derived polyetheramides (AAPEAs) were investigated in detail. The star-shaped AAPEAs showed high-efficient and broad-spectrum antibacterial activity against the E nterococcus faecium , S taphylococcus aureus , K lebsiella pneumoniae , A cinetobacter baumannii , P seudomonas aeruginosa , and E nterobacter species (ESKAPE) pathogens. In addition, the antibacterial activity was significantly affected by the type of amino acid. L-Trp-T403, which was obtained from L-tryptophan and polyetheramine, exhibited the best antibacterial activity with the minimum inhibitory concentration (MIC) of 1 µg/mL against methicillin-resistant S. aureus (MRSA). Time-kill kinetics and multi-passage resistance tests experiments indicated that L-Trp-T403 could rapidly kill bacteria within 1 h. This compound also showed potent antibacterial activity against bacteria over many passages. Moreover, the AAPEAs exhibited outstanding stability and long-term antibacterial activity in complex mammalian body fluids, as well as good biocompatibility, low hemolytic activity, slight toxicity for mammalian cell (L929) and low in vivo toxicity. The antibacterial activity of L-Trp-T403 was found to be based on the disruption of bacterial membranes, which leads to the leakage of the internal cytoplasm. The AAPEAs possessed high antibacterial and anti-biofilm activity, thus, they are promising to be used as long-term and biofilm-disrupting antimicrobial agents. The growing epidemic of MDR-bacteria is becoming a severe public health threat. Here, a series of amino acids derived polyetheramides (AAPEAs) with a star-shaped polyether amide scaffold was synthesized. The star-shaped AAPEAs displayed broad-spectrum antibacterial activity against Gram-positive, Gram-negative bacteria and drug-resistant bacteria MRSA. Notably, the star-shaped AAPEAs were stable under plasma conditions and showed outstanding stability and long-term antibacterial activity in various complex mammalian fluids. Moreover, these star-shaped AAPEAs not only inhibited the formation of biofilms but also disrupted the established biofilms. Furthermore, the membrane-active AAPEAs eradicated bacteria via the fast membrane lytic mechanism, thus plausibly overcoming the MDR effect. These results demonstrate that membrane-active AAPEAs can serve as emerging long-term and biofilm-disrupting antimicrobial agents to treat biofilm-related infections. [Display omitted] [ABSTRACT FROM AUTHOR]

Loose nanofiltration membrane exhibits significant advantages in removing organic pollutants due to its high selectivity at a lower operating pressure. Herein, a novel zwitterionic loose polyamide separation layer was designed and formed on the modified polyethersulfone substrate to obtain the zwitterionic loose nanofiltration (ZLNF) membrane with high water permeability and good antifouling properties. The BAPP-TMC polyamide layer was fabricated by the interfacial polymerization between 1,4-bis(3-aminopropyl)piperazine (BAPP) and trimesoyl chloride (TMC). Afterward, the BAPP-TMC polyamide layer was grafted with zwitterions by a facile surface modification. Owing to the fabrication of the relatively loose polyamide structure with zwitterions, the prepared ZLNF-0.2 membrane presented an ultra-high pure water permeability of 148.5 L m−2 h−1 bar−1 while maintaining relatively good removal capacities for organic pollutants. The removal rates for humic acid (HA, 100 ppm) and Congo Red (CR, 100 ppm) were 98.1 % and 97.6 %, respectively. Furthermore, the good hydrophilicity and strong surface hydration effect of zwitterions endowed the ZLNF membranes with excellent anti-organic fouling and antibacterial adhesion properties. The good antibacterial abilities of ZLNF membranes were also proved by the fluorescence staining results. Due to the effective separation performance and good antifouling properties, the fabricated ZLNF membranes present great application potential in removing natural organic matter and dyes. [Display omitted] • A novel zwitterionic loose BAPP-TMC polyamide separation layer was fabricated. • ZLNF membranes presented good antifouling properties. • The ZLNF-0.2 membrane exhibited an ultra-high pure water permeability. • The ZLNF-0.2 membrane showed efficient removal abilities for humic acid and dyes. [ABSTRACT FROM AUTHOR]

The ever-increasing carbon emission requires the development of advanced carbon capture and storage technology. As one of the most promising approaches, the adsorption of CO 2 over porous carbon (PC) has been intensively studied due to the low cost, easy synthesis, and high adsorption capacity of PC. However, further improvement in its CO 2 adsorption capacity is hindered by the unclear relationship between each physicochemical property and the adsorption capacity. Recently machine learning (ML) has achieved giant progress in predicting the adsorption capacity of PCs. However, due to the intrinsic "black box" property of ML, the quantitative relationship between each physicochemical property and corresponding adsorption capacity cannot be derived. Herein, first random forest was well trained to predict the CO 2 adsorption capacity. Then, Shapley Additive Explanations, a powerful visualization tool, was adopted to provide insights into such an uncovered relationship. The results showed that textural property is more important than chemical composition in affecting CO 2 uptake. Furthermore, SHAP indicated that high CO 2 adsorption capacity appeared at low pressure, temperature of 298 K with specific surface area of 1100–1300 m2/g, micropore volume of 0.4–0.6 cm3/g, mesopore volume of < 0.1 cm2/g, carbon of 72–86 wt%, hydrogen of 1–4 wt%, oxygen of < 16 wt%, and nitrogen of < 1 wt%. This study sheds light on the understanding of the CO 2 adsorption mechanism on PC and guides the design of next-generation high-performance PC for carbon capture and storage. • Four different machine learning models were trained for predicting CO 2 adsorption capacity of porous carbon. • Random Forest model shows the best predication accuracy than others do. • Shapley Additive Explanations was used to elucidate the structure-performance relationship. • The desired physicochemical parameter of porous carbons for achieving high CO 2 adsorption is presented. [ABSTRACT FROM AUTHOR]

To improve the anti-biofouling property of polyvinylidene fluoride (PVDF) membrane, three kinds of antibacterial graphene oxide (GO) derivatives were prepared, including imidazole-functionalized GO (Im-GO) and quaternized GO (Q-GO) synthesized by chemical grafting method, and GO loaded with silver nanoparticles (GO-Ag) synthesized by in-site reduction method. The structural characteristics and antibacterial abilities of three kinds of GO derivatives were characterized and investigated. It was demonstrated that GO could be used as a good carrier to prepare the anti-biofouling modifiers. Correspondingly, Im-GO/PVDF, Q-GO/PVDF, and GO-Ag/PVDF ultrafiltration membranes were fabricated using the phase inversion method. In contrast with the blank PVDF membrane, all the GO derivatives/PVDF membranes showed greatly improved permeability and anti-biofouling property. Significantly, the inhibition zone test and fluorescence staining experiment were carried out to investigate the differences between Im-GO, Q-GO, and GO-Ag in the antibacterial mechanisms. The corresponding results suggest that the imidazole and quaternary ammonium salt groups grafted on Im-GO and Q-GO possess great anti-leaching characteristics, while the loss of Ag+ from GO-Ag is relatively obvious. Therefore, Im-GO and Q-GO synthesized by chemical grafting method have greater potential as the anti-biofouling membrane modifiers, considering the accumulation of harmful ions in water and possible reduction in antibacterial stability for GO-Ag. [Display omitted] • Im-GO, Q-GO, and GO-Ag with good antibacterial property were synthesized. • Im-GO, Q-GO, and GO-Ag were used as the anti-biofouling modifiers for membranes. • The anti-leaching characteristics of anti-biofouling modifiers were investigated. • Im-GO and Q-GO exhibited better anti-leaching characteristics than GO-Ag. [ABSTRACT FROM AUTHOR]

The removal of U (VI) from wastewater is an arduous technological task wherein biofouling caused by microorganisms severely depletes the relevant properties of adsorbents. Herein, the zeolitic imidazole frameworks dubbed ZIF-90 were functionalized with amidoxime via the production of a diaminomaleonitrile intermediate to manufacture a highly efficient U (VI)-adsorbing material with antibacterial properties called amidoxime-appended ZIF-90 (ZIF-90-A). The crystal and pore structures of ZIF-90 and its modified materials were characterized by FT-IR, XRD, SEM, XPS and BET. ZIF-90-A has a superior uranium-uptake capacity (490.2 mg/g) at pH 5, which is close to the pH of wastewater. At the same time, ZIF-90-A also exhibited outstanding antimicrobial properties. Values for the minimum inhibitory concentration (MIC) of ZIF-90-A were measured to be 125 and 250 μg/mL against Staphylococcus aureus and Escherichia coli , respectively. In addition, ZIF-90-A displayed good selectivity for the adsorption of UO 2 2+; moreover, the uranium-uptake capacity of ZIF-90-A did not exhibit an obvious reduction when the adsorbent was subjected to five adsorption–desorption cycles. These results suggest that ZIF-90-A is a viable choice for the efficient removal of U (VI) from nuclear wastewater. [Display omitted] • A novel U (VI) adsorbent ZIF-90-A with good anti-fouling property is prepared. • ZIF-90-A shows good antimicrobial activity against S. aureus and E. coli (MICs = 125 ~ 250 μg/mL). • ZIF-90-A shows efficient U (VI) adsorption performance (Q e = 490.2 mg/g, pH = 5). • The possible mechanisms of U (VI) adsorption and antimicrobial are illustrated. [ABSTRACT FROM AUTHOR]

Abstract: Nanosheet-based three-dimensional (3D) hierarchical rosette-like In2O3 microspheres and hollow microspheres are successfully prepared by a hydrothermal and subsequent annealing process. The formation mechanism of In(OH)3(En)2 microsphere precursors is investigated systematically, and the possible chemical reactions at each stage are proposed. The complexing agent and the surfactant are the two important factors to control the morphologies and microstructures of the final products. The as-synthesized hierarchical In2O3 microspheres show excellent sensing response to volatile organic compounds such as acetone and toluene gases. The detection limit can be as low as ∼500ppb level in atmosphere. In addition, the sensing mechanism based on the change of surface resistance is discussed. Such novel In2O3 microspheres may be a promising candidate for sensor application in detecting acetone or toluene in different environments. [Copyright &y& Elsevier]

Abstract: Uniform single-crystalline In(OH)3 hollow microcubes have been synthesized in large quantities via a hydrothermal reaction of InCl3 with NaF and ethylene glycol (EG) at 140–220°C for 12h. Porous In2O3 hollow microcubes with a polycrystalline cubic structure can be obtained via calcining In(OH)3 precursors at 400°C for 2h in air. Controlled Synthesis of In(OH)3 and In2O3 hollow microcubes with the average edge lengths in the range of 2.0–4.7μm can be achieved by changing the hydrothermal reaction temperature. The In(OH)3 hollow microcubes were formed via an EG-assisted oriented attachment growth route using HF bubbles as the templates. Photocatalytic activities of the as-synthesized porous In2O3 hollow microcubes were studied at room temperature. The results indicated that the hollow In2O3 nanostructures display high photocatalytic activity in the photodegradation of rhodamine B and methyl orange. [Copyright &y& Elsevier]

Abstract: Porous Ni3Al intermetallic material with a mean pore diameter of around 1μm was prepared by step sintering Ni and Al powder pressed compacts in vacuum furnace at 900°C. The electrocatalytic activity of the as-fabricated porous Ni3Al material as an electrode for hydrogen evolution reaction (HER) in alkaline solutions was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) techniques. It is found that the onset potential of porous Ni3Al for HER shifted in the positive direction favoring hydrogen generation with lower overpotential, compared with foam Ni and dense Ni electrodes. Effects of electrolyte concentration and temperature on HER as well as the electrochemical stability in alkaline solution were investigated and the electrochemical activation energy was determined for the porous Ni3Al. The increased activity for HER was attributed to the high porosity, an increased electrochemical surface area and the nanostructure of porous Ni3Al electrode. The corrosion tests showed that the corrosion resistance of porous Ni3Al electrode changed during the immersion process due to the formation of passive film layers. [Copyright &y& Elsevier]

Abstract: LaPO4, LaPO4:Ce3+ and LaPO4:Ce3+, Tb3+ particles with different morphologies and sizes have been successfully synthesized via a simple EDTA assisted hydrothermal method. The effects of the doping components, pH value, and the chelating reagent on the phases, structures and morphologies were well investigated by means of X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Photoluminescent (PL) spectra and kinetic decays were used to characterize the fluorescent properties of the samples. The results reveal that all the samples are of high purity and assigned to the single-crystalline monoclinic structure of LaPO4 phase. The aspects ratio of the nanostructures synthesized in acid synthetic condition is larger than those obtained in alkaline solution. Additionally, the Ce3+ or/and Tb3+ doped LaPO4 particles show less smoother surface compared with pure LaPO4. Furthermore, the tendency for anisotropic growth under hydrothermal conditions can be simply enhanced by selecting the chelating ligands (EDTA). The possible growth mechanism of the LaPO4:Ln3+ (Ln = Ce3+, Tb3+) nanostructures has been proposed as well. Upon ultraviolet excitation, LaPO4:Ce3+ and LaPO4:Ce3+, Tb3+ phosphors show the characteristic 5d–4f emissions of Ce3+ and 5D4–7F j (j = 6–3) emission lines of Tb3+, respectively. [ABSTRACT FROM AUTHOR]

The design of hierarchical nanostructures with a controlled composition arrangement is a promising strategy to achieve high ion transport and enhanced charge storage for high-performance supercapacitor electrode development. Herein, we report a high-energy-density electrode based on CoP/Mo-NiCoP nanoplates array on carbon cloth templated by the metal-organic frameworks (MOFs). The unique hierarchical 3D structure provides an extremely large surface that enables excellent accessibility to the active surface sites, promoting electrochemical energy storage performance effectively. In addition, according to the density functional theory (DFT) calculation, Mo-doped in CoP/NiCoP nanoplates results in a desired electronic structure to enhance electronic transfer capability. As a result, the CoP/Mo-NiCoP electrode presents a high specific capacity of 892.6 C g−1 (248 mAh g−1) at the current density of 1 A g−1, as well as good rate capability (78.9% of capacity at 20 A g−1), and long-term cycling stability (82.6% retention after 10000 cycles at 4 A g−1). Furthermore, the assembled supercapacitor yielded a high energy density of 64.7 Wh kg−1 at 800 W kg−1 with an operating voltage of 1.6 V, outperforming most asymmetric supercapacitors. This work shows a promising hierarchical nanomaterial array for the development of high-performance flexible supercapacitors. [ABSTRACT FROM AUTHOR]

Abstract: In2O3 nanowires have been synthesized on a large-area surface by direct thermal oxidation of indium grains coated with an Au film at 700–850°C under the flow of O2. The indium grains were used as both a reagent and a substrate for the growth of In2O3 nanowires. The as-synthesized In2O3 nanowires were characterized by transmission electron microscopy, scanning electron microscopy and Raman spectrum. It was found that the In2O3 nanowires were a polycrystalline with the body centered cubic structure and had a controllable diameter in the range of 60–250nm with lengths of up to 10μm by varying the heating temperature. A possible mechanism was also proposed to account for the growth of these In2O3 nanowires. [Copyright &y& Elsevier]

Single perovskite alloy nanowire capable of emitting lasing broadly and continuously is highly desirable for the miniaturization and integration of all-photonic devices. However, due to the limitation of a soft and dynamic crystal lattice and the synthesized strategy, single perovskite nanowire with single-band lasing emission is mostly observed. Here, we propose a solid-solid anion-diffusion process to construct single CsPbCl 3-3x Br 3x perovskite alloy nanowire with a widely tunable bandgap from 2.41 to 2.82 eV and a regularly geometrical structure. We realized a broadly and continuously tunable nanolaser from 480 to 525 nm in single CsPbCl 3-3x Br 3x nanowire, as different spots along the length serve as a gain medium and microcavity simultaneously. The kinetics and atomic-scale mechanism of solid-solid anion diffusion were analyzed by a quantitative study and theoretical calculations, giving a small activation energy of halide migrations. The dynamics of carrier transportations revealed the energy transfer in single CsPbCl 3-3x Br 3x alloy nanowire, that's why broadly tunable lasers are difficult to realize in single isolated nanowire. Our work proposes a new strategy to construct single perovskite alloy nanowire for achieving a broadly and continuously tunable laser, clarifies the mechanism and kinetics of anion diffusion in perovskite alloy nanowires. We realized a broadly and continuously wavlength-tunable lasers (480–525 nm) in single perosvkite alloy nanowire. An anion-diffusion process was proposed to construct the nanowire with a widely tunable bandgap (2.41–2.82 eV), the kinetics and atomic-scale mechanism of anion diffusion were analyzed. The carrier dynamics were systematically studied to clarify the energy transfer of single perovskite alloy nanowire. Image 1 • A broadly and continuously (480–525 nm) tunable laser is realized in single CsPbCl 3-3x Br 3x nanowire. • Single CsPbCl 3-3x Br 3x nanowire with a widely tunable bandgap (2.41–2.82 eV) is realized via an anion-diffusion process. • The kinetics and atomic-scale mechanism are clarified in theory and experiment. • The energy transfer is revealed by time-resolved photoluminescence measurements in single nanowire. [ABSTRACT FROM AUTHOR]

We demonstrate the observation of the strong excitons-photons coupling in pencil-like ZnO microwires at room temperature. The pencil-like ZnO microwires with high optical quality were fabricated by using a carbothermal growth method at 1100 °C. The strong coupling of excitons and photons is evidenced by using angle-resolved photoluminescence spectroscopy. By scanning excitations spot from the arm to the tip of the pencil-like ZnO microwires, we found that the confinement of the tip is weaker than that of the arm due to the shrinked size. With increasing the excitation power, the lowest energy states of exciton-polariton modes are remarkably populated, and lasing phenomena are observed. By using the coupled oscillator model, the polariton effect can be well described. [ABSTRACT FROM AUTHOR]