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The widespread use of chlorination (Cl 2 ) in drinking water systems causes the selection of chlorine-resistant bacteria commonly with dense extracellular polymeric substance (EPS) against chlorine permeation, posing significant threat to public health. Herein, a nanowire-assisted electroporation (EP) via locally enhanced electric field was combined with Cl 2 to construct the synergistic EP/Cl 2 disinfection, with the purposes of inducing cell pores for chlorine permeation and bacterial inactivation. The synergistic effects of EP/Cl 2 were observed for inactivation of chlorine-resistant Bacillus cereus (G+, 304 μg DOC-EPS/10 9 CFU) and Aeromonas media (G-, 35.8 μg), and chlorine-sensitive Escherichia coli (G-, 5.1 μg) that were frequent occurrence in drinking water systems. The EP/Cl 2 enabled above 6 log B. cereus inactivation (undetectable live bacteria) at 1.5 V-EP and 0.9 mg/L-Cl 2 , which was much higher than the individual EP (1.11 log) and Cl 2 (1.13 log) disinfection. The cell membrane integrity, intracellular free chlorine levels, and morphology analyses revealed that the electroporation-induced pores on cell wall/membrane destructed the bound EPS barrier for chlorine permeation, and the pore sizes were further enlarged by chlorine oxidation, hence facilitating bacterial inactivation via destroying the cell structures. The excellent disinfection performance for tap water and lake water also suggested its sound application potentials., Competing Interests: Declaration of Competing Interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, and there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2022. Published by Elsevier Ltd.)

Still ∼10% of world's population has no sustainable access to centralized water supply system, causing millions of deaths annually by waterborne diseases. Here, we develop polypyrrole nanowire arrays (PPyNWs)-modified electrodes by polymerization of pyrrole on graphite felt for point-of-use water disinfection via low-voltage electroporation. A flow-through mode is specially applied to alleviate diffusion barrier of pyrrole in the porous graphite felt for uniform PPyNWs growth. The flow-through disinfection device using the optimized PPyNWs electrode achieves above 4-log removal for model virus (MS2) and gram-positive/negative bacteria (E. faecalis and E. coli) at applied voltage of 1.0 V and fluxes below 1000 and 2500 L/m 2 /h. Electroporation is recognized as the dominant disinfection mechanism by using square-wave alternating voltage of ±1.0 V to eliminate the electrochemical reactions. In-situ sampling experiments reveal that anode acts as the main disinfection function due to its electric field attraction with negatively charged E. coli cells. The live/dead baclight staining experiments indicate an adsorption-desorption process of E. coli cells on anode, and the adsorption-desorption balance determines the disinfection abilities of PPyNWs anode. Under 1.0 V and 2000 L/m 2 /h, the disinfection device enables above 4-log E. coli removal in tap water within 7-day operation with energy consumption below 20 mJ/L, suggesting its sound application potential for point-of-use water disinfection., (Copyright © 2021. Published by Elsevier Ltd.)

A kind of surface plasmon resonance sensor based on grapefruit photonic crystal fiber (PCF) filled with different numbers of silver nanowires has been studied in this paper. The surface plasmon resonance modes and the sensing properties are investigated comprehensively using the finite element method (FEM). The simulation results show that the intensity sensitivity is related to nanowire numbers and the distance between two nanowires. The optimum value obtained is 2,400 nm/RIU, corresponding to a resolution of 4.51 × 10(-5) RIU with a maximum distance of 2 μm. To a certain extent, the PCF filled with more nanowires is better than with just one. Furthermore, the air holes of grapefruit PCF are large enough to operate in practice. Moreover, the irregularity of the filled nanowires has no effect on sensitivity, which will be very convenient for the implementation of experiments.

Poor adhesion between silver nanomaterials and substrates seriously restricts the development of electronic composite devices. In this work, flexible and conductive silver nanowires/fibroin/degummed silk (AgNWs/fibroin/dSF) composite fibers with high adhesion and conductivity via capillarity-assisted assembly for electromagnetic interference (EMI) shielding are designed and fabricated by a facile and scalable all-solution dip-coating method. The nanocomposite fiber possesses high conductivity with a resistance of 8.8 Ω/cm at a low AgNWs/fibroin loading of 19.3 wt%. The assistance of the capillary force in the fiber highly increases the mass of deposited AgNWs. Furthermore, the AgNWs show high adhesion on the fibers in the tape-peel test. The enhanced deposition factors and mechanisms are detailly investigated. Moreover, the composite fibers are further woven into a soft and flexible fabric. The composite fabric shows an absorption-dominated EMI shielding performance with an efficient shielding effectiveness of 38 dB. The capillarity-assisted assembly is an attractive procedure for constructing high-conductive and uniform coatings for a wide application. [Display omitted] [ABSTRACT FROM AUTHOR]

• A highly sensitive and strain-insensitive fiber-based wearable temperature sensor. • A conductive ligand chemically grafts onto the surface of silver nanowires. • Theoretically calculate the electrical conductivity properties of the ligands. • Silver nanowire network shows high conductivity with decreased junction resistance. • Modified silver nanowires tightly absorb on a stretchable covering yarn. The real-time monitoring of human temperature can facilitate efficient family health supervision, disaster diagnosis, and treatment. To meet these requirements, there is an urgent need to develop fibre-based temperature sensors with high sensitivity, fast response rates, and excellent stability. This study investigated the positive temperature characteristics of a stretchable and strain-insensitive temperature sensor with a chemically modified silver nanowire (AgNW). The regulation of the surface polymer on the AgNWs using a conductive ligand of polyaniline-L-cysteine ethyl ester hydrochloride (PANI-LCO) improved the network conductivity by decreasing the junction resistance. In addition, the pristine flexibility and helicoid structure of a spandex polyurethane (SP) covered yarn substrate proved advantageous for the ultra-stretchability of the temperature sensor. Therefore, the synergistic effect of the PANI-LCO-AgNWs and the substrate endowed the composite fibre-based temperature sensor with a high-temperature coefficient of resistance (TCR) of 47.4%/°C and a high stretchability of up to 120%. Furthermore, this study investigated the actual characteristics of the sensor required for the high-performance monitoring of human temperatures. Moreover, theoretical calculations of the electrical distribution of the PANI-LCO ligands further confirmed the experimental chemical modification. A fibre-based temperature sensor can be integrated and woven or sewn onto a cloth or glove with high adaptability. This work provides an efficient strategy to control the surface chemical structure of metal nanomaterials as well as the design of fibre-based temperature sensors that are promising for wearable healthcare management systems, artificial intelligence, electronic skin, and smart robots. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergistic electroporation/chlorination was constructed to promote i-ARG removal. • DC-EP/Cl 2 promoted the damage of ARB cells for i-ARG leakage and removal. • DC-EP/Cl 2 decreased significantly the HGT frequency than individual treatment. • DC-EP/Cl 2 had much lower energy consumption for i-ARG removal in tap water. • DC-EP/Cl 2 exhibited excellent stability of i-ARG removal within 7-day operation. Conventional chlorination (Cl 2) is inefficient to eliminate intracellular antibiotic resistance genes (i-ARGs) of antibiotic-resistant bacteria (ARB) due to the chlorine permeation barrier and oxidative competition of cell wall/membrane. Herein, we proposed an efficient strategy by constructing synergistic nanowire-induced electroporation (DC-EP) and Cl 2 (DC-EP/Cl 2) with H 2 -reduced TiO 2 nanowire (TiO x NW) electrodes, attempting to promote i-ARG removal via DC-EP-induced cell damage for chlorine permeation and i-ARG leakage. DC-EP/Cl 2 (∼3.7 log and ∼ 60.5 J/L/log) exhibited excellent synergistic effects for ARB inactivation (Escherichia coli) and i-ARG removal (tet(W) , aac(3)-II , and bla TEM – 1), which achieved much larger i-ARG removal and lower energy consumption than the individual 1.5 V-DC-EP (∼0.05 log) and 10 mg/L-Cl 2 (∼0.5 log and ∼ 262.0 J/L/log). Analyses of i-ARG/e-ARG abundances, bacterial cell integrity, and cell morphology indicated that DC-EP-induced cell pores provided channels of chlorine permeation, which was accompanied with oxidative enlargement of cell pores for i-ARG leakage and subsequent degradation. DC-EP/Cl 2 exhibited 15–90 times lower frequency of horizontal gene transfer than the individual Cl 2 disinfection. The TiO x NW-based DC-EP/Cl 2 exhibited excellent stability of i-ARG removal (undetectable ARG abundance and ∼ 20.3 J/L/log) for treating 103 CFU/mL ARB-contaminated tap water within 7-day continuous operation, suggesting its great application potential to alleviate ARG dissemination risk for drinking water. [ABSTRACT FROM AUTHOR]

Biocompatible flexible conductive composite fibers have attracted great research interest because of multitude of their potential applications, such as wearable devices, biomedical sensors, and actuators. Herein, highly conductive and flexible silver nanowire (AgNW)/fibroin composite fibers were fabricated by using a wet‐spinning technique. The composite fiber conductivity was as high as 5670 S/cm at an AgNW concentration of 29.1 wt%. The composite fibers also exhibited high flexibilities and could be folded without losing their conductivities. Furthermore, the composite fiber fabricated with a 3× draw ratio exhibited a breaking strain of 27.3% and breaking stress of 118.1 cN/dtex. Our attempt to produce such biocompatible flexible conductive composite fibers by using sustainable regenerated silk fibroins and compatible AgNWs via wet spinning may provide a practical way for fabricating functional biocompatible fiber materials. [ABSTRACT FROM AUTHOR]

A temperature sensor based on hollow fiber (HF) filled with graphene-Ag composite nanowire and liquid is presented. The coupling properties and sensing performance are numerically analyzed by finite element method using wavelength and amplitude interrogations. Results show that the sensor exhibiting strong birefringence with x-polarized peak provides much higher sensitivities and better signal-to-noise ratio (SNR) than y-polarized, which is more suitable for temperature detection. The graphene-Ag composite nanowire can not only solve the oxidation problem but also avoid the metal coating. Moreover, it provides better performance than other similar works like Au-Ag nanowire-filled, Au nanowire-filled, and Ag nanowire-filled sensors. Contrary to the blue shift of traditional SPR temperature sensors, the resonance peak shifts to the longer wavelength in our device when temperature increases and the high sensitivity 9.44 nm/ °C is obtained. The influences of nanowire diameter, grapheme-layer thickness on the designed sensor, are also investigated. This work can provide a reference for developing a high sensitivity, real-time, remote sensing, and distributed temperature SPR sensor. [ABSTRACT FROM AUTHOR]

We propose a photonic crystal fiber (PCF)-based surface plasmons resonance (SPR) temperature sensor in this paper, and using the dual function of PCF filled with different shapes of nanowires and analyte to realize temperature sensing and have designed an experimental setup. Different shapes of nanowires with the mixed liquid are filled into the proposed octagon PCF. The simulation results indicate that not only structure parameters of PCF but also the shapes of filled nanowires play a key role to the sensing. A blue-shift in the SPR resonant peak is shown with the temperature increases. Different loss spectra present that a higher confinement loss for low temperature and the octagon PCF filled with elliptical nanowires shows a more obvious peak shift and higher sensitivity, which is about 500 pm/°C and the corresponding sensor resolution is 2.0 × 10 −2 °C. This PCF sensing system has great practical value and significance for its advantage of high sensitivity. [ABSTRACT FROM AUTHOR]

Well-aligned ZnO nanowire arrays have been prepared, and p-MgZnO has been deposited onto the nanowires to form core–shell heterostructures. Transmission electron microscopy confirms the formation of n-ZnO/p-MgZnO core–shell nanowire heterostructures. Under injection of a continuous current, random lasing with a threshold current of around 15 mA has been observed from the heterostructures. The low threshold may be due to the relatively high crystalline quality of the ZnO nanowires as well as the carrier confinement in the heterostructures. [ABSTRACT FROM AUTHOR]

A surface plasmon resonance (SPR) sensor based on hollow‐core photonic crystal fibre (HC‐PCF) filled with silver nanowires is designed. The analyte and silver nanowires are full filled in the air holes of the HC‐PCF to realise the SPR sensing, which is more convenient than silver coated in operation. The designed sensor is analysed through numerical simulations and demonstrated by experiments. All the results show that a blue‐shift is obtained with increase of the analyte refractive index (RI), and the silver nanowires concentration has no effect on spectral sensitivity. The highest average spectral sensitivity of 14 240 nm/RIU is obtained by experiments, which is higher than that previously reported for the same type of sensors. The sensor is useful for detecting small analyte RI changes, and can also provide a reference for the implementation and application of PCF‐SPR sensors with high sensitivity. [ABSTRACT FROM AUTHOR]

Dual functional composite films with high electromagnetic interference (EMI) shielding and photothermal conversion properties are urgently demanded for modern microelectronic devices, especially to be used in an extreme environment. Here, flexible and lightweight MXene/AgNW/PU composite foam films were constructed by incorporating 1D AgNWs and 2D MXene in a PU matrix for highly efficient electromagnetic interference shielding and photothermal conversion. The 3D conductive network of AgNWs and MXene as well as the porous structure with multiple interfaces facilitated a high shielding effectiveness of 50 dB at a low density of 0.15 g/cm3 in X-band with a high absorption-dominated shielding efficiency of 86%. In the frequency of Ku-band, the composite foam film presented a higher shielding efficiency of 60 dB with the absorption efficiency as high as 95%, representing an excellent absorption-dominated shielding performance. The composite foam film remained an excellent EMI shielding efficiency of 41.5 dB after 1000 cycles of compression and release. Furthermore, the composite foam film showed a high photothermal conversion property. The flexible and lightweight MXene/AgNW/PU composite foam films provided a facile strategy for applications of EMI shielding and photothermal conversion in aerospace as well as portable smart electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

Supercapacitor with favorable power density and short charging time has attracted tremendous attention. However, its energy-storing capability is still far less than the battery's. Pseudocapacitive materials such as polypyrrole exhibit great potential in the high-capacitance devices. Here, pyrrole was in-situ polymerized on the hollow polyurethane thread (PPy/HPU), then the PPy/HPU acted as working electrode for the electrochemical polymerization of pyrrole to construct PPy nanowires on its outer surface (EPPy-PPy/HPU thread). EPPy-PPy/HPU electrode with abundant PPy nanowires exhibits higher slope value of Δ J /2 vs. scan rates (1.43 mF cm−1) than the PPy/HPU's one (0.327 mF cm−1), indicating its larger active area for electrochemical reaction. Thus, EPPy-PPy/HPU performs a superior capacitance (475.9–221.3 mF cm−2 at 0.25–1.00 mA cm−2) than the PPy/HPU (249.1–92.5 mF cm−2). Two EPPy-PPy/HPU electrodes were penetrated by PVA/H 2 SO 4 gel electrolyte to assemble a solid-state supercapacitor (SSC), which presents a dominant diffusion-controlled capacitance, good rate capability (only falling from 36.25 to 29.5 mF cm−1) and stable energy density (0.915–1.286 μWh cm−1). This fiber-shaped SSC has great potential in the application of wearable energy storage devices. • The combination of spinning and multiple morphology regulation for electrode. • A hollow thread electrode with polypyrrole nanowires for supercapacitors. • Polypyrrole nanowires with good capacitive contribution and rate capability. [ABSTRACT FROM AUTHOR]

Abstract Nickel cobalt oxide is widely studied as the electrocapacitive material for energy storage devices because of its high electrical conductivity and multiple transition states for generating abundant Faradaic redox reactions. Constructing well-defined core/shell structures with effective charge transfer path and large surface area is one of the feasible ways to develop efficient electrocapacitive materials. This study proposes a novel insight at the first time to investigate the electrocapacitive performance of the NiCo 2 O 4 core/shell electrodes comprising different core morphologies of one-dimensional (1D) nanowire (NW) and two-dimensional (2D) nanosheet (NS). The nickel molybdenum oxide shell synthesized on different NiCo 2 O 4 cores shows similar morphologies, suggesting the core structure has limited influences on the growth of the shell. Simple sheet-on-wire and sheet-on-sheet configurations are therefore obtained for the core/shell structures with 1D NW and 2D NS cores, respectively. A specific capacitance (C F) of 5.53 F/cm2 is obtained at 5 mV/s for the core/shell electrode composed of the 1D NW core, along with the C F retention of 65% after 2000 cycles repeated charge/discharge process. This study provides a novel viewpoint for constructing efficient energy storage devices via carefully designing the core morphology for the core/shell structures as the electrocapacitive material. Highlights • The core morphology effects on core@shell structures and performances are studied. • Nanowire (NW) and nanosheet (NS) are made as core for NiCo 2 O 4 @NiMo x O y structures. • NiCo 2 O 4 @NiMo x O y structures show simple combination of core and shell morphologies. • NiCo 2 O 4 NW@NiMo x O y electrocapacitively performs better than NiCo 2 O 4 NS@NiMo x O y. • The 1-D NW core provides efficient charge transfer paths and better performances. [ABSTRACT FROM AUTHOR]