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[Display omitted] Plasmon-mediated chemical reaction (PMCR) is a highly attractive field of research. Here we report in situ surface-enhanced Raman spectroscopic (SERS) monitoring of plasmonic-mediated S S bond-forming reaction. The reaction is thought to be a self-coupling reaction proceeding by photoinduced aromatic S C bond arylation. Surprisingly, the S C arylation and S S coupling are found to be occurred on both partially oxidized silver and silver nanoparticles. The results demonstrated that silver oxide or hydroxide and small molecule donor sacrifice agent played a crucial role in the reaction. This work facilitates the in-situ manipulation and characterization of the active silver electrode interface in conjunction with electrochemistry, and also establishes a promising new guideline for surface plasmon resonance photocatalytic reactions on metal nanostructures with high efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] Novel two-dimensional MXene with unique optical and electrical properties has become a new focus in the field of sensing. In particular, their metallic conductivity, good biocompatibility and high anchoring ability to biomaterials make them attractive candidates. Despite such remarkable properties, there are certain limitations, such as low oxidative stability. MXene-Metal interactions are an effective strategy to maintain the long-term stability of MXene, while also improving the electrochemical activity and optical properties. Herein, a series of MXene/Ag nanocomposites including Ti 3 C 2 /Ag, Nb 2 C/Ag and V 2 C/Ag were designed based on the surface chemistry characteristics of MXene, where MXene served as the substrate for in-situ growth of silver nanoparticles via self-reduction of Ag(NH 3) 2 +. The results showed that V 2 C MXene has the strongest self-reducing ability due to its multiple variable valence states, larger interlayer space and more reactive groups. Moreover, V 2 C/Ag exhibited unexpected oxygen reduction reaction catalytic activity and photothermal performance. In view of which, an electrochemiluminescence-photothermal (ECL-photothermal) immunosensor was developed using V 2 C/Ag as ECL anchor and photothermal reagent for ultrasensitive detection of Lipolysis stimulated lipoprotein receptor. This work not only provides a simple and effective synthesis method of MXene supported metal nanocomposites, but also provides more inspirations for exploring the efficient biosensing strategies. [ABSTRACT FROM AUTHOR]

A self-standable, transparent, self-adhesive, bending resistant and highly adaptive SERS substrate has been fabricated by depositing Ag nanoparticles (AgNPs) on CdS nanowires (CdSNWs) embedded in a specially prepared nanofilm matrix, and further used for the in-situ, at real-time, sensitive and selective detection of urea in human sweat and plant leaves. [Display omitted] Wearable SERS substrates have gained substantial attention for health monitoring and other applications. Current designs often rely on conventional polymer substrates, leading to discomfort and complexity due to the need of additional adhesive layers. To address the issues, we fabricate a flexible, uniform, ultrathin, transparent and porous SERS substrate via depositing Ag nanoparticles (AgNPs) onto the CdS nanowires (CdSNWs) grown on the surface of a prepared nanofilm (AgNPs-CdSNWs/nanofilm). Unlike the wearable SERS substrates reported in literature, the one presented in this work is self-adhesive to a variety of surfaces, which simplifies structure, enhances comfort and improves performance. Importantly, the new SERS substrate as developed is highly stable and reusable. Artificial sample tests revealed that the substrate showed a great enhancement factor (EF) of 4.2 × 107 and achieved a remarkable detection limit (DL) of 1.0 × 10−14 M for rhodamine 6G (R6G), which are among the highest records observed in wearable SERS substrates reported in literature. Moreover, the substrate enables at real-time and in-situ reliable monitoring of urea dynamics in human sweat and plant leaves, indicating its applicability for health analysis and in precision agriculture. [ABSTRACT FROM AUTHOR]

[Display omitted] Efficient utilizing CO 2 is crucial approaches in achieving carbon neutralization. One of the challenges lies in the in-situ conversion of low concentration CO 2 found in waste gases. This study introduces a novel heterogeneous catalyst known as silver nanoparticles in porous N -heterocyclic carbene polymer (Ag@POP-NL-3). The catalyst is synthesized via a streamlined pre-coordination method. Ag@POP-NL-3 exhibits uniform distribution of silver nanoparticles, a porous structure and nitrogen activation groups. It demonstrates high efficiency and selectivity in absorbing and activating CO 2 and enabling the conversion of low concentration CO 2 (30 vol%) from lime kiln waste gas into cyclic carbonate under mild conditions. This catalytic system achieves both CO 2 capture and resource utilization of CO 2 simultaneously, effectively fixing low-concentration CO 2 from waste gases into C 2+ valuable chemicals. This approach elegantly addresses two goals in one solution. [ABSTRACT FROM AUTHOR]

The antimicrobial property of core-shell silver nanoparticles (Ag@mSiO 2) is better than that of yolk-shell silver nanoparticles (Ag@YSiO 2), which plays a protective role in silk cultural relics without interference. [Display omitted] Silver nanoparticles coated with organic-inorganic hybrid silica or inorganic silica have antimicrobial ability, and the coating can also effectively improve the dispersion and stability of the particles. The slow release of silver ions (Ag+) can improve the antimicrobial activity of silver nanoparticles. The synthesized nanoparticles are light yellow, which does not affect the look and feel of the silk cultural relics and meets the requirements of the principle of minimum interference. Two kinds of silver-based nanoparticles were synthesized: silver core-shell nanoparticle (Ag@mSiO 2) and silver yolk-shell nanoparticle (Ag@YSiO 2). The morphology, surface properties and Ag+ release efficiency of two nanoparticles were characterized. The antimicrobial effects of two nanoparticles on Aspergillus niger (A. niger) and Penicillium citrinum (P. citrinum) were compared. Both of Ag@mSiO 2 and Ag@YSiO 2 had uniform size and good stability. Two nanoparticles had pore structure and silver nanocore, which provided the basis for the dissolution and exchange of Ag+. Because more silver ions were released, Ag@mSiO 2 had higher antimicrobial activity than Ag@YSiO 2 for A. niger and P. citrinum. For various silk samples, Ag@mSiO 2 exhibited excellent antimicrobial properties. Meanwhile, there was little change in the color and tearing strength of Ag@mSiO 2 coated silk. [ABSTRACT FROM AUTHOR]

[Display omitted] Pseudomonas aeruginosa bacteria originate severe infections in hospitalized patients and those with chronic debilitating diseases leading to increased morbidity and mortality, longer hospitalization and huge financial burden to the healthcare system. The clinical relevance of P. aeruginosa infections is increased by the capability of this bacterium to grow in biofilms and develop multidrug resistant mechanisms that preclude conventional antibiotic treatments. Herein, we engineered novel multimodal nanocomposites that integrate in the same entity antimicrobial silver nanoparticles (NPs), the intrinsically antimicrobial, but biocompatible biopolymer chitosan, and the anti-infective quorum quenching enzyme acylase I. Acylase present in the NPs specifically degraded the signal molecules governing bacterial cell-to-cell communication and inhibited by ∼ 55 % P. aeruginosa biofilm formation, while the silver/chitosan template altered the integrity of bacterial membrane, leading to complete eradication of planktonic bacteria. The innovative combination of multiple bacteria targeting modalities resulted in 100-fold synergistic enhancement of the antimicrobial efficacy of the nanocomposite at lower and non-hazardous towards human skin cells concentrations, compared to the silver/chitosan NPs alone. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanocomposites of ZIF-8, carbon nanodots and silver nanoparticles are prepared. • A novel fluorescent sensing strategy is developed for the detection of H 2 O 2 and glucose based on AgNP-CD-ZIF-8. • Excellent analytical performances are achieved, which might inspire future studies on MOF assembly. In this study, a novel fluorescent biosensor is developed for the detection of H 2 O 2 and glucose based on Zeolitic Imidazolate Framework-8 (ZIF-8) nanocomposites. ZIF-8 encapsulating carbon nanodot (CD) exhibits bright fluorescence emission. After further loading of AgNP, the fluorescence is quenched, which is mainly based on the excited electron transfer from CD to AgNP. Besides, the excitation wavelength of CD falls within the adsorption range of AgNP, which leads to efficient inhibition of the excitation energy. The as-prepared AgNP-CD-ZIF-8 nanocomposites can be utilized as a highly sensitive platform for the analysis of H 2 O 2 and glucose. In the presence of glucose, H 2 O 2 can be generated by the catalysis of glucose oxidase (GOD), which induces the etching of AgNP and subsequent recovery of CD-ZIF-8 fluorescence. This "turn on" biosensor can be applied for facile and convenient quantification of H 2 O 2. It can also be further extended to detect glucose in real samples after combining specific catalytic effect of GOD. The analytical performances are excellent, which demonstrates great potential for practical utility. [ABSTRACT FROM AUTHOR]

[Display omitted] Autonomous self-propelled micromachines based on semiconductors are at the forefront of environmental pollutants degradation research to palliate the effects of the contamination arising from the constant manufacturing of new products. Nonetheless, testing these micromotors with real-life products is almost an unexplored field, limiting the degradation of pollutants to single-component aqueous solutions or suspensions at the laboratory scale, which hinders the translation of these micromachines into useful systems. Herein, Ag 3 VO 4 has been devised as a micromotor by an asymmetric deposition of a thin layer of Pt, giving rise to Pt/Ag 3 VO 4 micromotors (Janus particle). Their motion capabilities have been demonstrated under UV light in fuel-free conditions. Their photocatalytic performance at laboratory scale has been confirmed for the degradation of Rhodamine B while, as a first approximation of a real-life application, the degradation of an energy drink has also been tested. During this latter exploration, the Pt/Ag 3 VO 4 micromotors were corroded by the citric acid present in the pollutant, releasing Ag nanoparticles into the media. As a proof of concept, the position of the generated Ag nanoparticles' surface plasmon resonance absorption maximum has been demonstrated to show a dependency on the concentration of citric acid. [ABSTRACT FROM AUTHOR]

[Display omitted] Silver nanoparticles (AgNPs) have found widespread commercial applications due to their unique physical and chemical properties. However, their relatively poor stability remains a main problem. An ideal way to improve the stability of AgNPs is not only to endow colloidal stability to individual nanoparticles but also to protect them from environmental factors that induce their agglomeration, like variation of ionic strength and pH, presence of macromolecules, etc. Mesoporous calcium carbonate vaterite crystals (CaCO 3 vaterite) have recently attracted significant attention as inexpensive and biocompatible carriers for the encapsulation and controlled release of both drugs and nanoparticles. This work aimed to develop an approach to load AgNPs into CaCO 3 vaterite without affecting their properties. We focused on improving the colloidal stability of AgNPs by using different capping agents, and understanding the mechanism behind AgNPs loading and release from CaCO 3 crystals. Various methods were applied to study the AgNPs and CaCO 3 crystals loaded with AgNPs (CaCO 3 /AgNPs hybrids), such as scanning and transmission electron microscopy, X-ray diffraction, infrared and mass spectrometry. The results demonstrated that polyvinylpyrrolidone and positively charged diethylaminoethyl-dextran can effectively keep the colloidal stability of AgNPs during co-precipitation with CaCO 3 crystals. CaCO 3 /AgNPs hybrids composed of up to 4 % weight content of nanoparticles were produced, with the loading mechanism being well-described by the Langmuir adsorption model. In vitro release studies demonstrated a burst release of stable AgNPs at pH 5.0 and a sustained release at pH 7.5 and 9.0. The antibacterial studies showed that these hybrids are effective against Escherichia coli , methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa , three important bacteria responsible for nosocomial infections. The developed approach opens a new way to stabilise, protect, store and release AgNPs in a controlled manner for their use as antimicrobial agents. [ABSTRACT FROM AUTHOR]

[Display omitted] Flexible pressure sensors have received tremendous attention for various wearable applications. However, it remains a critical challenge to develop a flexible pressure sensor with excellent sensitivity performances and multiple advantageous properties. Herein, a high-performance flexible piezoresistive pressure sensor PMIA@PDA@Ag was developed, which sensitive component is consisted of Ag nanoparticles decorated polydopamine (PDA)-modified meta -aramid (poly(m -phenylene isophthalamide), PMIA) nanofibrous membrane. The PMIA@PDA@Ag pressure sensor shows excellent mechanical, thermal insulation, antibacterial and breathable properties, as well as remarkable sensing performances including high sensitivity, wide detectable pressure range, rapid response speed and good cyclic durability. In addition, it also shows great sensing performances in monitoring various human behaviors in real-time, including large-scale motions and subtle physiological signals. [ABSTRACT FROM AUTHOR]

[Display omitted] The size of silver nanoparticles (Ag NPs) and loading amount of Ag NPs onto their substrate/carrier are two key factors for their efficient applications. Herein, we present a facile method for in situ synthesizing ultrafine and highly loaded Ag NPs on the surface of tannin-coated catechol-formaldehyde resin (TA-CFR) nanospheres. TA-CFR nanospheres act as green and highly efficient reducing agents for converting silver ions (Ag+) into Ag NPs, and the size of resultant Ag NPs is only ∼ 7.5 nm, and the Ag NPs loading capacity of TA-CFR is as high as 61.5 wt%, both of which contribute to the very high specific surface area of Ag NPs. Consequently, the as-synthesized TA-CFR@Ag composites show high catalytic performance, and the catalytic rate for the reduction of 4-nitrophenol is almost 10 times higher than that of the control. Meanwhile, TA-CFR@Ag composites also possess high antibacterial activity, efficiently inhibiting the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Furthermore, tannin coating (thickness: ∼ 15 nm) minimizes the aggregation of Ag NPs, and enhances the reusability and stability of resultant Ag NPs, because of their high surface charges (the zeta potential is up to −65.5 ± 1.9 mV) and strong coordination capability with Ag NPs. This work provides a new frontier to develop multifunctional nanomaterials focusing on the green catalyst synthesis and environmental-remedy applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag or Au nanoparticles were deposited on ZnIn 2 S 4 via in situ sulfur vacancy induced metal precursor reduction approach. • ZIS/Ag(Au)/FeTCPP system was applied for CO 2 photoreduction. • Ag function as a promoter for interfacial charge transfer from ZnIn 2 S 4 to the FeTCPP and greatly facilitates the CO production. • The loaded Au is beneficial to H 2 generation. The construction of hybrid catalysts composed of inorganic semiconductors and molecular catalysts shows great potential for achieving high photocatalytic carbon dioxide (CO 2) conversion efficiency. In this study, ZnIn 2 S 4 was first synthesized via a solvothermal route. Gold (Au) and silver (Ag) nanoparticles were then deposited on ZnIn 2 S 4 via the reduction of noble metal precursor by sulfur vacancy defects. The obtained composite was further combined with tetra(4-carboxyphenyl)porphyrin iron(III) chloride (FeTCPP) molecular catalyst for efficient photocatalytic CO 2 conversion. The roles of different noble metal nanoparticles in charge separation and interfacial electron transfer have been comprehensively studied. The photocatalytic performance and photoelectrochemical characterizations demonstrate that the introduction of Ag or Au nanoparticles is beneficial for charge separation. More importantly, the presence of Ag nanoparticles plays a crucial role in promoting the interfacial charge transfer between ZnIn 2 S 4 and FeTCPP, whereas, Au nanoparticles function as active sites for the water reduction reaction. [ABSTRACT FROM AUTHOR]

Nanostructured titanium substrates provide inherent antimicrobial activity against drug-resistant fungi and bacteria, mimicking structures on the surface of naturally antimicrobial organisms. The addition of silver nanoparticles onto the nanostructures provides a secondary chemical antimicrobial mechanism and increases the efficacy in the response for both microbial species via low concentrations of silver. [Display omitted] Titanium and its alloys are commonly used implant materials. Once inserted into the body, the interface of the biomaterials is the most likely site for the development of implant-associated infections. Imparting the titanium substrate with high-aspect-ratio nanostructures, which can be uniformly achieved using hydrothermal etching, enables a mechanical contact-killing (mechanoresponsive) mechanism of bacterial and fungal cells. Interaction between cells and the surface shows cellular inactivation via a physical mechanism meaning that careful engineering of the interface is needed to optimse the technology. This mechanism of action is only effective towards surface adsorbed microbes, thus any cells not directly in contact with the substrate will survive and limit the antimicrobial efficacy of the titanium nanostructures. Therefore, we propose that a dual-action mechanoresponsive and chemical–surface approach must be utilised to improve antimicrobial activity. The addition of antimicrobial silver nanoparticles will provide a secondary, chemical mechanism to escalate the microbial response in tandem with the physical puncture of the cells. Hydrothermal etching is used as a facile method to impart variant nanostrucutres on the titanium substrate to increase the antimicrobial response. Increasing concentrations (0.25 M, 0.50 M, 1.0 M, 2.0 M) of sodium hydroxide etching solution were used to provide differing degrees of nanostructured morphology on the surface after 3 h of heating at 150 °C. This produced titanium nanospikes, nanoblades, and nanowires, respectively, as a function of etchant concentration. These substrates then provided an interface for the deposition of silver nanoparticles via a reduction pathway. Methicillin-resistant Staphylococcous aureus (MRSA) and Candida auris (C. auris) were used as model bacteria and fungi, respectively, to test the effectiveness of the nanostructured titanium with and without silver nanoparticles, and the bio-interactions at the interface. The presence of nanostructure increased the bactericidal response of titanium against MRSA from ∼ 10 % on commercially pure titanium to a maximum of ∼ 60 % and increased the fungicidal response from ∼ 10 % to ∼ 70 % in C. auris. Introducing silver nanoparticles increased the microbiocidal response to ∼ 99 % towards both bacteria and fungi. Importantly, this study highlights that nanostructure alone is not sufficient to develop a highly antimicrobial titanium substrate. A dual-action, physical and chemical antimicrobial approach is better suited to produce highly effective antibacterial and antifungal surface technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag or Au nanoparticles were deposited on ZnIn 2 S 4 via in situ sulfur vacancy induced metal precursor reduction approach. • ZIS/Ag(Au)/FeTCPP system was applied for CO 2 photoreduction. • Ag function as a promoter for interfacial charge transfer from ZnIn 2 S 4 to the FeTCPP and greatly facilitates the CO production. • The loaded Au is beneficial to H 2 generation. The construction of hybrid catalysts composed of inorganic semiconductors and molecular catalysts shows great potential for achieving high photocatalytic carbon dioxide (CO 2) conversion efficiency. In this study, ZnIn 2 S 4 was first synthesized via a solvothermal route. Gold (Au) and silver (Ag) nanoparticles were then deposited on ZnIn 2 S 4 via the reduction of noble metal precursor by sulfur vacancy defects. The obtained composite was further combined with tetra(4-carboxyphenyl)porphyrin iron(III) chloride (FeTCPP) molecular catalyst for efficient photocatalytic CO 2 conversion. The roles of different noble metal nanoparticles in charge separation and interfacial electron transfer have been comprehensively studied. The photocatalytic performance and photoelectrochemical characterizations demonstrate that the introduction of Ag or Au nanoparticles is beneficial for charge separation. More importantly, the presence of Ag nanoparticles plays a crucial role in promoting the interfacial charge transfer between ZnIn 2 S 4 and FeTCPP, whereas, Au nanoparticles function as active sites for the water reduction reaction. [ABSTRACT FROM AUTHOR]

Nanostructured titanium substrates provide inherent antimicrobial activity against drug-resistant fungi and bacteria, mimicking structures on the surface of naturally antimicrobial organisms. The addition of silver nanoparticles onto the nanostructures provides a secondary chemical antimicrobial mechanism and increases the efficacy in the response for both microbial species via low concentrations of silver. [Display omitted] Titanium and its alloys are commonly used implant materials. Once inserted into the body, the interface of the biomaterials is the most likely site for the development of implant-associated infections. Imparting the titanium substrate with high-aspect-ratio nanostructures, which can be uniformly achieved using hydrothermal etching, enables a mechanical contact-killing (mechanoresponsive) mechanism of bacterial and fungal cells. Interaction between cells and the surface shows cellular inactivation via a physical mechanism meaning that careful engineering of the interface is needed to optimse the technology. This mechanism of action is only effective towards surface adsorbed microbes, thus any cells not directly in contact with the substrate will survive and limit the antimicrobial efficacy of the titanium nanostructures. Therefore, we propose that a dual-action mechanoresponsive and chemical–surface approach must be utilised to improve antimicrobial activity. The addition of antimicrobial silver nanoparticles will provide a secondary, chemical mechanism to escalate the microbial response in tandem with the physical puncture of the cells. Hydrothermal etching is used as a facile method to impart variant nanostrucutres on the titanium substrate to increase the antimicrobial response. Increasing concentrations (0.25 M, 0.50 M, 1.0 M, 2.0 M) of sodium hydroxide etching solution were used to provide differing degrees of nanostructured morphology on the surface after 3 h of heating at 150 °C. This produced titanium nanospikes, nanoblades, and nanowires, respectively, as a function of etchant concentration. These substrates then provided an interface for the deposition of silver nanoparticles via a reduction pathway. Methicillin-resistant Staphylococcous aureus (MRSA) and Candida auris (C. auris) were used as model bacteria and fungi, respectively, to test the effectiveness of the nanostructured titanium with and without silver nanoparticles, and the bio-interactions at the interface. The presence of nanostructure increased the bactericidal response of titanium against MRSA from ∼ 10 % on commercially pure titanium to a maximum of ∼ 60 % and increased the fungicidal response from ∼ 10 % to ∼ 70 % in C. auris. Introducing silver nanoparticles increased the microbiocidal response to ∼ 99 % towards both bacteria and fungi. Importantly, this study highlights that nanostructure alone is not sufficient to develop a highly antimicrobial titanium substrate. A dual-action, physical and chemical antimicrobial approach is better suited to produce highly effective antibacterial and antifungal surface technologies. [ABSTRACT FROM AUTHOR]

The synthesized Ag@CoMo-LDH electrode exhibited distinguished electrocatalytic performance compared with most reported advanced OER electrocatalysts. [Display omitted] Modulating electronic resistance properties and enhancing both active site populations and per-site activity are highly desirable for the application of layered double hydroxides (LDHs) in the electrocatalytic oxygen evolution reaction (OER). Herein, a metal-support structure consisting of silver (Ag) nanoparticles supported by MoO 4 2− intercalated Co-LDH (CoMo-LDH) nanocages (Ag@CoMo-LDH) was developed using a sacrificial template method and a subsequent spontaneous strategy. The resultant hybrid was shown to be a highly efficient OER electrocatalyst in alkaline media. The required overpotential of Ag@CoMo-LDH for affording a geometric current density of 10 mA cm−2 is as low as 205 mV, which is not only significantly lower than that of separate CoMo-LDH or Ag nanoparticles but also superior to that of most developed OER electrocatalysts reported recently. The constituents and respective work mechanism of Ag@CoMo-LDH are discussed in detail. The superior performance of Ag@CoMo-LDH is related to the unique construction and the effective and stable heterointerfaces between Ag nanoparticles and CoMo-LDH, which accelerate the electron and mass transfer, provide a large number of new active sites and optimize the activity of the original sites. Impressively, Ag@CoMo-LDH also exhibited promising practical prospect on account of the remarkable cyclic and long-term stability. This finding demonstrates that pointedly integrating multiple strategies into one system is a promising way to construct new LDH-based OER electrocatalysts with synthetically improved performance, providing a promising model for developing advanced electrocatalysts in energy conversion devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The plating mechanical of metallic Li on carbon microspheres is revealed. • Li-Ag alloy enables high physical plating/stripping and carbon spheres structural are utilized as a Li cage. • Behavior behind the enhanced Li nucleation, plating and stripping is investigated. • Silver-coated N-doped onion-like carbon spheres (Ag@NCS) obtain by simple one-step injection pyrolysis. Lithium metal is considered as a promising anode material for next-generation secondary batteries, owing to its high theoretical specific capacity (3860 mA h g−1). Nevertheless, the practical application of Li in lithium metal batteries (LMBs) is hampered by inhomogeneous Li deposition and irreversible "dead Li", which lead to low coulombic efficiency (CE) and safe hazards. Designing unique lithiophilic structure is an efficient strategy to control Li uniformly plating /stripping. Here, we report the silver (Ag) nanoparticles coated with nitrogen-doped onion-like carbon microspheres (Ag@NCS) as a host to reduce the nucleation overpotential of Li for dendrite-free LBMs. The Ag@NCS were prepared by a simple one-step injection pyrolysis. The lithiophilic Ag is demonstrated to be priority selective deposition of Li in the carbon cage. Meanwhile, the onion-like structure benefits to uniform lithium nucleation and dendrite-free lithium during cycling. Impressively, we successfully captured lithium metal on different hosts at atomic scale, further proving that Ag@NCS can effectively and uniformly deposit Li. Besides, Ag@NCS show a superiorly electrochemical performance with a low nucleation overpotential (∼1 mV), high CE and stable cycling performance (over 400 cycles at 0.5 mA cm−2) compared to the Ag-free onion-like carbon in LMBs. Even under harsh conditions (1 mA cm−2, 4 mA h cm−2), Ag@NCS still present superior cycling stability for more than 150 cycles. Furthermore, a full cell composed of LiFePO 4 cathode exhibits significantly improved voltage hysteresis with low voltage polarization. This work provides a new choice and route for the design and preparation of lithiophilic host materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gold and silver nanoparticles have been homogeneously disseminated on BP nanosheet by a light-assisted self-reduction. • Robust SERS chips were successfully developed by assembling BP@Au-Ag nanocomposites into bilayer membrane. • A reliable in-situ recyclable detection strategy has been demonstrated utilizing the tape-mediated SERS chip. • The effective preservation of BP was realized based on the principle of fresh-keeping film. Self-cleaning surface-enhanced Raman scattering (SERS) substrates dependent on versatile two-dimensional semiconductors offer an efficient channel for the sensitive monitoring and timely degradation of hazardous molecules. Herein, a kind of sophisticated SERS-active nanocomposites was developed by incorporating Au-Ag nanoparticles onto black phosphorus (BP) nanosheets via photo-induced self-reduction. Combining the substantial electromagnetic "hot spots" triggered by bimetallic plasma coupling effect and the efficient charge transfer from BP to probe molecules, the proposed nanocomposites featured attractive SERS enhancement, facilitating a limit of detection down to 4.5 × 10−10 M. Attributed to the remarkable restriction of electron-hole recombination stemming from "Schottky contact", the photocatalytic activity of BP was prominently boosted, demonstrating a complete degradation time as short as 65 min. Furthermore, the disgusting instability of BP was considerably hindered by inserting the nanocomposites into various bilayer matrices with diverse hardness and viscosity inspired by cling film principle. Moreover, a significantly elevated collection rate high to 93.1% for in-situ detection was also achieved by the as-manufactured flexible SERS chips based on tape. This study illustrates a clear perspective for the development of versatile BP-based SERS chips which might facilitate sensitive analysis and treatment of perilous contaminants in complicated real-life scenarios. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Ag-modified Bi 2 MoO 6 was obtained for ppb-level NH 3 gas detection. • The highest response (G g /G a = 37.6 to 200 ppb NH 3) under 20% RH. • The synergistic effect of metal–semiconductor junctions and noble metal catalytic. Noble metal-doping and modification are proved effective in improving the gas-response performance of semiconductor sensors. In this study, we developed a promising Bi 2 MoO 6 (BMO)-based gas sensor capable of sensing ppb-level NH 3 at room temperature via introducing silver (Ag). The BMO samples with different Ag doping and modification ratios were successfully formed via one-step solvothermal and glucose reduction techniques, respectively, which could be confirmed by the results of X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) techniques. Compared to bare BMO, the gas-sensing properties of both Ag-doped and Ag surface-modified BMO samples were improved to various extents, respectively. In particular, the 5% Ag-modified BMO sensor with the highest response (G g /G a = 37.6 to 200 ppb NH 3), long-term stability, and low threshold concentration (50 ppb) at 20% RH. Based on the spillover effect and metal–semiconductor junctions of Ag nanoparticles, the enhanced sensing response towards NH 3 can be thoroughly illustrated. Combined with the first-principles calculations, the adsorption energy, density of states, and charge transfer of Ag-modified BMO were further performed to demonstrate the high sensing response and ultra-low detection limit. [ABSTRACT FROM AUTHOR]

[Display omitted] A robust method to prepare silver nanoclusters (AgNCs) inside a methacrylic acid-ethyl acrylate (MAA-EA) nanogel is proposed, where AgNCs were produced within the nanogel scaffold via UV-photoreduction. The impact of UV irradiation time on the formation of AgNCs and their application in biolabeling and antimicrobial properties were examined. The AgNCs formation is described by two stages; (1) Ag n (n = 2–8) nanoclusters formation between 0 and 25 min, and (2) larger silver nanoparticles (AgNPs) formed via aggregation inside the nanogel. The antimicrobial performance depended on the size and concentration of silver ions (Ag+). A maximum inhibitory concentration (MIC) of 1.1 ppm was observed for antimicrobial test with yeast, and a MIC of 11 and 22 ppm was recorded for Escherichia. coli and Staphylococcus aureus respectively. Combining with the green illumination property of AgNCs (emitted at 525 nm) with dead yeast, it could be used for biolabeling. By tuning the size through photoirradiation, the nanogel templated AgNCs is a promising candidate for antimicrobial and biolabeling applications. [ABSTRACT FROM AUTHOR]

Silver nanoparticles with vanadium oxide nanowires were obtained using the vanadium oxide quantum dots as both reductants and stabilizers. It was loaded into electrospun dressing for efficient bacteria-infected wound healing as confirmed by both in vitro and in vivo tests. [Display omitted] Silver nanoparticles (AgNPs) have been widely recognised as effective antibacterial materials in textiles for enhancing wound healing. However, high loadings of AgNPs are toxic and expensive. Thus, it is ideal to prepare AgNPs in a favourable nanostructure for stable and effective conjugation with the textile carrier by selecting a reductant and stabiliser that contributes to the antibacterial effect. Here, silver nanoparticles/vanadium oxide nanowires (Ag/VO x NWs) were prepared via a one-step reduction strategy using vanadium oxide quantum dots (VO x QDs) as both the reductant and stabiliser. VO x QDs possess antibacterial properties, which aid in minimising the applied silver content while enhancing bactericidal performance. Silver can self-aggregate into nanoparticles as well as promote the formation of vanadium oxide nanowires (VO x NWs). Accordingly, the Ag/VO x NWs exhibited remarkable antibacterial effects against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The nanowire structure of the Ag/VO x NWs was favourable for effective loading into a sodium alginate (SA) gel fabric to form a wound dressing. The effective loading of Ag/VO x NWs on SA was conducive to the complete dispersion of the bacteriostatic agent and enhanced the antibacterial activity of AgNPs. The wound dressing efficiently suppressed the growth of wound bacteria and promoted wound healing in vivo. [ABSTRACT FROM AUTHOR]

[Display omitted] Globally, drug-resistant bacteria are a potential threat to human society owing to the overuse of antibiotics and thus, non-antibiotic bactericides are urgently needed. Herein, an innovative antibacterial nanoplatform based on quaternized chitosan (QCS)/ silver (Ag)/ cobalt phosphide (CoP) nanocomposites is envisaged for achieving near-infrared (NIR) laser-inducible rapid sterilisation. In the core-shell hybrids, Ag nanoparticles (NPs) with a size of ∼ 25 nm were uniformly deposited on CoP nanoneedles, upon which a layer of QCS (approximately 10 wt%), is coated. Numerical calculations revealed that under NIR irradiation, high-energy hot electrons arising from the surface plasmon resonance effect of Ag migrate into the interface between Ag and CoP, and amplify the photothermal effect of CoP. Meanwhile, photo-excited electrons from CoP are transported onto Ag NPs because the Schottky heterostructure facilitates the production of reactive oxygen species. Ag loading simultaneously enhances the photocatalytic and photothermal effects of CoP, achieving rapid antibacterial activity synergistically. The QCS coating improves the dispersibility of power in an aqueous system and provides contact between the antiseptics and bacteria. The ternary QCS/Ag/CoP nanocomposites achieved greater than 99.6% inactivation against S. aureus and E. coli within 10 min. In addition, the nanocomposites were confirmed to be noncytotoxic to mammals. Consequently, the QCS/Ag/CoP nanoplatforms possess great potential for rapid and effective antibacterial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The introduction of various drugs onto commercial soft contact lenses (CLs) has emerged as a potentially effective strategy for treating microbial keratitis (MK) because drug-loaded CLs can maintain a controlled drug concentration which leaded to enhanced drug bioavailability and reduced side effects in ocular tissues. In this study, silver nanoparticles modified with zwitterionic poly (carboxybetaine- co -dopamine methacrylamide) copolymer (PCBDA@AgNPs) as novel anti-infective therapeutics were prepared and firmly immobilized onto soft CLs through mussel-inspired surface chemistry. The obtained PCBDA@AgNPs coated CL (PCBDA@AgNPs-CL) remained the excellent transparency of commercial CLs and exhibited strong and broad-spectrum antimicrobial activities. We systematically explored the mechanism and found that the functional CLs can effectively inhibit the growth of microbial biofilms via a synergic "resist–kill–remove" strategy due to the zwitterionic surface and sustained release of silver ions. Significantly, in vitro cell cytotoxicity and in vivo subcutaneous implantation experiments proved the significant biosafety of PCBDA@AgNPs-CL. Furthermore, PCBDA@AgNPs-CL was successfully employed for the in vivo treatment of MK rabbit models, demonstrating excellent abilities to eradicate microbe-induced ocular infections and to prevent the destruction and irreversible structural alterations of corneal tissues. Collectively, PCBDA@AgNPs-CL is therefore a highly promising therapeutic device to significantly boost the efficacy for MK treatment. [ABSTRACT FROM AUTHOR]

A complex nanostructure composed of silver nanocrystals randomly immobilized carbon nanoparticles randomly immobilized carbon nanoparticles was in situ synthesized by one-step solvothermal method using Toluene as carbon sources. [Display omitted] Silver nanoparticles (Ag NPs) have attracted extensive research interest in bioimaging and biosensing due to their unique surface plasmon resonance. However, the potential aggregation and security anxiety of Ag NPs hinder their further application in biomedical field due to their high surface energy and the possible ionization. Here, binary heterogeneous nanocomplexes constructed from silver nanoparticles and carbon nanomaterials (termed as C-Ag NPs) were reported. The C-Ag NPs with multiple yolk structure were synthesized via a one-step solvothermal route using toluene as carbon precursor and dispersant. The hydrophilic functional groups on the carbon layer endowed the C-Ag NPs excellent chemical stability and water-dispersity. Results showed that C-Ag NPs demonstrated excellent safety profile and excellent biocompatibility, which could be used as an intracellular imaging agent. Moreover, the C-Ag NPs responded specifically to hydroxyl radicals and were expected to serve as a flexible sensor to efficiently detect diseases related to the expression of hydroxyl radicals in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] Burn wounds are susceptible to bacterial infections and are usually accompanied by a large amount of exudate, making the treatment of burn wounds a challenge in the clinic. Here, we developed a biodegradable cryogel with high water absorption and good antibacterial and antibiofilm activity based on gelatin (GT) and silver nanoparticles (Ag NPs) to promote burn wound healing. The porous GT/Ag cryogel had a swelling ratio of up to 4000%, effectively absorbing wound exudate and allowing for gas exchange. Moreover, the GT/Ag cryogel had an excellent killing effect on methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PA), which burn wounds are susceptible to, and can effectively remove mature biofilms. In the rat liver defect noncompressible hemorrhage model, GT/Ag cryogels with shape memory performance showed better hemostatic ability than commercial gelatin sponges. Most importantly, the GT/Ag cryogel was more effective than the TegadermTM dressing and GT cryogel in promoting wound contraction, collagen deposition, and angiogenesis and reducing inflammation in a PA-infected burn wound model. In addition, GT/Ag cryogels degraded in the body within 4 weeks, which alleviated the pain of peeling the dressing from the wound. Therefore, GT/Ag cryogels with outstanding antibacterial properties and effective absorption of wound exudates are excellent candidates for wound dressings to promote burn wound repair. [ABSTRACT FROM AUTHOR]

Ordered arrays of Ag nanoparticles-assembled cavities are fabricated by templated electrodeposition and post-growth. Oriented attachment and Ostwald ripening are proposed to drive the post-growth process. Such Ag cavity array shows high surface-enhanced Raman scattering sensitivity to pesticides (thiram and paraquat). [Display omitted] • Three-dimensional Ag nanostructure arrays have been fabricated by a simple method. • Ag nanoparticles-assembled micro-cavity arrays were achieved using templated electrodeposition and post-growth. • The three-dimensional substrate with dense hotspots showed high SERS sensitivity. • The fabricated SERS substrate showed high spectral uniformity and reproducibility. • Sensitive SERS detection of pesticide residues on fruits was realized. Three-dimensional (3D) plasmonic nano-arrays can provide high surface-enhanced Raman scattering (SERS) sensitivity, good spectral uniformity and excellent reproducibility. However, it is still a challenge to develop a simple and efficient method for fabrication of 3D plasmonic nano-arrays with high SERS performance. Here we report a facile approach to construct ordered arrays of silver (Ag) nanoparticles-assembled spherical micro-cavities using polystyrene (PS) sphere template-assisted electrodeposition and post-growth. The electrodeposited small Ag nanoparticles grow into bigger stable nanoparticles during the post-growth process, which could significantly improve the SERS sensitivity. The Ag nanoparticles-assembled 3D micro-cavity array provides much more hotspots in the excitation laser beam-covered volume than the two-dimensional counterpart. The relative standard deviation (RSD) of 612 cm−1 peak of rhodamine 6G (R6G) was calculated to be 8%, and the RSD of the characteristic peak taken from substrates of different batches was less than 10%. The detectable lower concentration as low as 1 fM was achieved for an aqueous solution of R6G. Such SERS substrate also showed high sensitivity to thiram (fungicide) and paraquat (herbicide) in water with limits of detection of 0.067 nM and 2.5 nM respectively. Furthermore, it also demonstrated that SERS detection of pesticide residues on fruits can be realized, showing a potential application in rapid monitoring food safety. [ABSTRACT FROM AUTHOR]

[Display omitted] Metallic nanoparticles of various shapes and sizes can be synthesised through a diversity of bottom-up pathways, such as precipitation induced by chemical reduction. Varying composition, by adjusting concentrations or adding/replacing species, is the predominant strategy to tune nanoparticles structures. However, controlling time down to the onset of precipitation, nucleation, should also provide a powerful means to control nanostructuration. We perform sequential reagent additions with a time resolution down to the millisecond. We use a millifluidic continuous flow setup consisting of tangential mixers in series, which allows flow rates up to dozens of litres per hour. We systematically vary both addition order and delay for each reagent involved in the synthesis of silver nanoplates. The resulting dispersions are compared using UV–visible spectroscopy, transmission electron microscopy and small-angle X-ray scattering. We show that synthesis pathways differing only in the order of sub-second additions lead to drastically different synthetic outcomes. Silver nanoparticles of different shapes and sizes, displaying an array of plasmonic colours, are synthesised at the same final composition by tuning the composition pathways along time. Our results unlock a previously inaccessible portion of the space of parameters, which will lead to an enhanced structural diversity, control and understanding of nanoparticles syntheses. [ABSTRACT FROM AUTHOR]

[Display omitted] A facile one-step method was developed to synthesize magnetically separable nanocomposite with a h-Fe 3 O 4 core and an Ag/polydopamine hybrid shell, of which exhibited excellent catalytic activity, antibacterial activity, and recyclability. A facile one-step method for synthesis of magnetic core–shell nanocomposite composed of h-Fe 3 O 4 (hollow Fe 3 O 4) core and stable PDA (polydopamine) shell with functional Ag NPs (silver nanoparticles) evenly distributed between them is developed. The h-Fe 3 O 4 @Ag/PDA nanocomposite showed excellent catalytic activity in the reaction for reducing azo dyes (methyl orange, methylene blue, and congo red), and the ratios of k values to the weight of h-Fe 3 O 4 @Ag/PDA were calculated to be 0.302, 0.0545, and 0.895 min−1 mg−1, respectively. Besides, the h-Fe 3 O 4 @Ag/PDA nanocomposite also exhibited good antibacterial activity in the experiment of culturing Bacillus subtilis , and the MIC (minimum inhibitory concentration) was as low as 12.5 μg/mL. Because the Ag NPs will not be leached in the solution under the protection of the PDA shell, the catalytic and antibacterial activities of h-Fe 3 O 4 @Ag/PDA nanocomposite could maintain more than 90% after five cycles. Intriguingly, this simple synthetic method can be extended to fabricate different multifunctional nanocomposites such as the spherical SiO 2 @Ag/PDA and rod-like Fe 2 O 3 @Ag/PDA. Overall, the facile fabrication process, the superior catalytic and antibacterial activity, and the excellent stability, endow the h-Fe 3 O 4 @Ag/PDA to be a promising nanocomposite. [ABSTRACT FROM AUTHOR]

The morphology optimization and non-metallic doping of Ag catalyst were realized by a facile and efficient plasma vulcanization treatment. The prepared sulfide derived Ag porous microrods (SD-AgPMRs) demonstrates high Faradaic efficiency and partial current density for CO production at low potentials in the electrocatalytic CO 2 RR. [Display omitted] • The SD-AgPMRs were firstly fabricated by a H 2 S plasma-enhanced low-temperature solid-state activation process. • This work realized the dual channel optimization of Ag electrode in morphology and composition. • Effective CO 2 reduction were realized which contribute to larger specific surface area and the introduction of S atoms. Metal electrode is considered as an ideal candidate for electrocatalytic carbon dioxide (CO 2) reduction considering its excellent chemical stability, application potential and eco-friendly properties. Optimization process such as morphological control, non-metallic doping, alloying is widely studied to improve the efficiency of metal electrodes. In this work, we successfully improved the CO 2 reduction performance of silver using a facile plasma vulcanization treatment. The obtained sulfide derived silver (Ag) porous microrods (SD-AgPMRs) are optimized from both morphology and composition aspects, and demonstrates high Faradaic efficiency and partial current density for carbon monoxide (CO) production at low potentials. The larger specific surface area of porous microrod structure and the improved adsorption energy of important intermediates in comparison with Ag foil are realized by introduction of sulfur (S) atoms after plasma vulcanization activation, as suggested by density functional theory (DFT) calculations. This work presents a novel strategy to optimize metal electrocatalysts for CO 2 reduction as well as to improve catalysis in other fields. [ABSTRACT FROM AUTHOR]

Tannic acid is used as a green and efficient stabilizer to fabricate all kinds of TMNPs including AuNPs, AgNPs, CuNPs and PdNPs. These TMNPs possess small sizes ranging from 1 nm to 6 nm, which is conducive to several catalytic reactions in aqueous solution, such as 4-nitrophenol (4-NP) reduction, CuAAC reactions and Suzuki–Miyaura coupling reactions. This present work has the superiorities of green raw material, simple and efficient preparation process, high catalytic activities, as well as the applicability and generality for various substrates. [Display omitted] Due to the good electrical, optical, magnetic, catalytic properties, transition metal nanoparticles (TMNPs) have been becoming more and more interesting in the fileds of environment, material, biomedicine, catalysis, and so on. Here, tannic acid (TA) is used as a green and efficient stabilizer to fabricate all kinds of TMNPs including AuNPs, AgNPs, CuNPs and PdNPs. These TMNPs possess small sizes ranging from 1 nm to 6 nm, which is conducive to several catalytic reactions in aqueous solution, such as 4-nitrophenol (4-NP) reduction, CuAAC reactions and Suzuki–Miyaura coupling reactions. AuNPs and PdNPs are found to have distinctly higher catalytic activities than AgNPs and CuNPs in the 4-NP reduction process. Especially, PdNPs show the highest catalytic activities with TOF up to 7200 h−1 in the 4-NP reduction. Furthermore, PdNPs also exhibit satisfying catalytic performance in the Suzuki–Miyaura coupling process, and CuNPs are catalytically active in the copper-catalyzed azide alkyne cycloaddition (CuAAC) reactions. The applicability and generality of PdNPs and CuNPs are respectively confirmed via the reaction between different substrates in the Suzuki–Miyaura coupling reactions and the CuAAC reactions. This work present a simple, fast, green and efficient strategy to synthesize TMNPs for multiple catalysis. [ABSTRACT FROM AUTHOR]

The Ag@Cu 2 O heterostructure core-shell nanostructure can achieve the sterilization of reactive oxygen groups under visible light. [Display omitted] Marine biological fouling has always been a hot research topic. In this study, silver @ cuprous oxide (Ag@Cu 2 O) core-shell nanoparticles were synthesized via in-situ synthesis method and developed an outstanding antibacterial activity. The bacteriostasis efficiency of Ag@Cu 2 O reached to 99% and 98% against Staphylococcus aureus and Pseudomonas aeruginosa , respectively. The minimum inhibitory concentration of Ag@Cu 2 O decreased from 113.6 μg/mL to 56.8 μg/mL compared with Cu 2 O. Ag@Cu 2 O had better antibacterial activity than Cu 2 O with lower content of Cu 2 O and was more environment friendly. The heterostructure formed at the interface between Ag and Cu 2 O promoted the separation and diffusion of photogenerated electron-hole pairs through the charge transfer channel and promoted the generation of reactive oxygen species. The outstanding antibacterial activity of Ag@Cu 2 O was strongly depended on the generation of the reactive oxygen species. Density functional theory and finite element method calculations demonstrated that the structure of core-shell improved photocatalytic efficiency. Additionally, synergetic effect of released Ag+ and Cu2+ also enhanced the bacteriostasis rate and the long-term antifouling performance in 60 days. Hence, the synthesized core-shell Ag@Cu 2 O can be applied as novel antifoulants in the marine field. [ABSTRACT FROM AUTHOR]

The illustration of the process of the PCBDA@AgNPs-MF for antibiofouling water disinfection. [Display omitted] Mature microfiltration (MF) membrane is a low-cost, effective, and promising technology to provide affordable purified water for people living in developing countries. However, the lack of disinfection ability and inherent membrane fouling problems have seriously restricted the large-scale application of conventional MF treatment system in producing safe drinking water. In this work, zwitterionic silver nanoparticles (AgNPs) with surface modification of poly(carboxybetaine acrylate- co -dopamine methacryamide) (PCBDA) copolymers were robustly immobilized onto commercial polyamide MF membrane via mussel-inspired chemistry for water disinfection. The designed microfiltration membrane, named as PCBDA@AgNPs-MF, exhibited integrated properties of high and stable payload of AgNPs, broad-spectrum anti-adhesive and antimicrobial activities, and easy removal of inactivated microbial cells from membrane surface. Ascribing to the synergetic effect of anti-adhesive and antimicrobial features brought by zwitterionic PCBDA@AgNPs, the biofilms growth on polyamide membrane surface was significantly inhibited, which showed potential access to achieve long-term biofouling resistance and maintain water flux for conventional MF membrane. As water disinfection device, these attributes enabled PCBDA@AgNPs-MF to effectively disinfect the model and natural bacteria-contaminated water. [ABSTRACT FROM AUTHOR]

[Display omitted] Bimetallic nanoparticles allow new and synergistic properties compared to the monometallic equivalents, often leading to unexpected results. Here we present on silver-iron nanoparticles coated with polyethylene glycol, which exhibit a high transverse relaxivity (316 ± 13 mM-1s−1, > 3 times that of the most common clinical benchmark based on iron oxide), excellent colloidal stability and biocompatibility in vivo. Ag-Fe nanoparticles are obtained through a one-step, low-cost laser-assisted synthesis, which makes surface functionalization with the desired biomolecules very easy. Besides, Ag-Fe nanoparticles show biodegradation over a few months, as indicated by incubation in the physiological environment. This is crucial for nanomaterials removal from the living organism and, in fact, in vivo biodistribution studies evidenced that Ag-Fe nanoparticles tend to be cleared from liver over a period in which the benchmark iron oxide contrast agent persisted. Therefore, the Ag-Fe NPs offer positive prospects for solving the problems of biopersistence, contrast efficiency, difficulties of synthesis and surface functionalization usually encountered in nanoparticulate contrast agents. [ABSTRACT FROM AUTHOR]

[Display omitted] The properties of stable gold (Au) nanoparticle dispersions can be tuned to alter their activity towards biomembrane models. Au nanoparticle coating techniques together with rapid electrochemical screens of a phospholipid layer on fabricated mercury (Hg) on platinum (Pt) electrode have been used to moderate the phospholipid layer activity of Au nanoparticle dispersions. Screening results for Au nanoparticle dispersions were intercalibrated with phospholipid large unilamellar vesicle (LUV) interactions using a carboxyfluorescein (CF) leakage assay. All nanoparticle dispersions were characterised for size, by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Commercial and high quality home synthesised Au nanoparticle dispersions are phospholipid monolayer active whereas Ag nanoparticle dispersions are not. If Au nanoparticles are coated with a thin layer of Ag then the particle/lipid interaction is suppressed. The electrochemical assays of the lipid layer activity of Au nanoparticle dispersions align with LUV leakage assays of the same. Au nanoparticles of decreasing size and increasing dispersion concentration showed a stronger phospholipid monolayer/bilayer interaction. Treating Au nanoparticles with cell culture medium and incubation of Au nanoparticle dispersions in phosphate buffered saline (PBS) solutions removes their phospholipid layer interaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag particles embedded nanoporous Ge was fabricated by one-step dealloying method. • Ag nanoparticles improve the electrical conductivity of the electrode. • The anode exhibits superior cyclic stability and rate capability. • Ample porous structure and good electrical conductivity guarantee the properties. Due to huge volume expansion and poor electrical conductivity, the commercial application of the promising Germanium (Ge) anode is restrained in lithium ion battery (LIB) field. Generally, conductive metals can improve the electron mobility in Ge. In that way, whether active materials or conductive metals account for a higher proportion in the anode is controversial in this field and needs to be clarified urgently. Herein, three Ge-based anodes with different ratios in conductive Ag are fabricated by a facile melt spinning and one-step dealloying method. It is found that Ag nanoparticles embedded three-dimensional nanoporous Ge (Ag/np-Ge) electrode with high active material ratio exhibits the best cycling stability among tested samples, delivering a high capacity of 953 mAh g−1 after 100 cycles at a current density of 100 mA g−1 and an excellent reversible capacity of 522 mAh g−1 after 200 cycles even at the high current density of 1000 mA g−1. The enhanced cycling stability can be attributed to the synergistic effect of nanoporous network-like structure and embedded Ag nanoparticles. A dramatical increase in electrical conductivity and activity of Ge by doping of Ag is confirmed by density functional theory (DFT) calculations. The work provides us an idea to rationally design the three-dimensional structure of active materials assisting with a proper ratio of conductive metals, which may promote the development of promising Ge anodes for LIBs with excellent cycling stability. [ABSTRACT FROM AUTHOR]

A new method to synthesize AgNPs and obtain stable high-loading AgNPs/lignin composite was presented. Water-soluble aminated alkaline lignin (AAL) was prepared by Mannich reaction using alkaline lignin as raw material, and the introduced amine groups in AAL had stronger ability to reduce Ag+. The composite formed by AgNPs and AAL, which could be easily separated from water, had good catalytic performance for the reduction of 4-nitrophenol to 4-aminophenol and could be easily recovered and reused for at least eight cycles. • Green synthesis of AgNPs through in-situ reduction by aminated alkaline lignin (AAL). • AAL had excellent ability to reduce Ag+ and improved the utilization rate of phenolic hydroxyl groups. • Easily-separated AgNPs/AAL composite had good catalytic performance for the reduction of 4-nitrophenol to 4-aminophenol. Green synthesis of silver nanoparticles (AgNPs) has received increasing attention. In this study, AgNPs were prepared through in-situ reduction by aminated alkaline lignin (AAL). Compared with alkaline lignin (AL), AAL exhibited stronger reduction capacity (increased by 36%) due to the introduced amine groups and better water solubility. Moreover, the coordination effect of amine groups on AAL improved the binding force between lignin and AgNPs. The content of AgNPs in AgNPs/AAL composite were 2.4 times higher than that in AgNPs/AL, such content could be further increased through increasing the reduction pH or prolonging the heating time. The results of XPS, XRD and TEM showed that the AgNPs were spherical and monodisperse with an average particle size about 17 nm. Additionally, the size of AgNPs was affected by the amination degree of lignin. AgNPs/AAL exhibited good catalytic performance for the reduction of 4-nitrophenol to 4-aminophenol, and this compound could be easily recovered and reused for at least eight cycles. [ABSTRACT FROM AUTHOR]

Selective dehydrogenation of formic acid is regarded as a universal strategy for providing a clean energy carrier (hydrogen, H 2) to reduce the dependence on fossil fuel. In this work, ultrafine PdAg nanoparticles (NPs) are successfully immobilized on NH 2 -functionalized metal–organic framework MIL-101(Cr) by a facile wet-reduction method. By virtue of amine group, the size of obtained PdAg NPs can be controlled into 2.2 nm, which are monodispersed on NH 2 -MIL-101(Cr) surface. In addition, the resulting Pd 0.8 Ag 0.2 NPs/NH 2 -MIL-101(Cr) catalyst systems demonstrate excellent catalytic activity for formic acid decomposition in mild condition, the turn over frequency (TOF) value can achieve as high as 1475 h−1 at 323 K, which is comparable to most of the reported noble metal heterogeneous catalysts for this catalytic reaction under similar conditions. The excellent catalytic kinetics is mainly attributed to the ultrafine size and high dispersion of PdAg NPs. Also, the amine group from NH 2 -MIL-101(Cr) support facilitates the O H bond dissociation of formic acid and improves the kinetics of formic acid decomposition. [ABSTRACT FROM AUTHOR]

Metal nanoparticles are used as additives in commercial products due to their antimicrobial properties. Apart from their high biocidal activity, it is widely observed that silver nanoparticles are toxic. Simultaneously, copper nanoparticles show fungicidal properties, but with limited effectiveness. Hence, it is suggested that a combination of Ag nanoparticles with Cu nanoparticles may decrease the toxic effects of silver while maintaining their high bioactivity. This paper presents the properties of Ag and Cu metal nanoparticles, and Ag-Cu and Cu-Ag bimetallic nanoparticles, synthesised in a continuous microwave reactor. The size of the metal nanoparticles obtained was in the range of 27–97 nm, and the size of the bimetallic nanoparticles was in the range of 32–184 nm, depending on the microwave irradiation, residence time, pH of the solution and concentrations of the reagents. Silver nanoparticles of particle size 97 nm revealed the highest antimicrobial activity (MIC = 10 mg/dm3). Simultaneously, silver nanoparticles did not show viral properties, compared to the copper and bimetallic nanoparticles, for which the virus titre was 1.06–1.50 log TCID50/cm3. In contrast to pure metal nanoparticles, the combination of silver and copper in bimetallic systems generated nanoparticles with no genotoxicity (rac(-)/rac(+) < 1.2). [ABSTRACT FROM AUTHOR]

Appealing physical and chemical properties are foreseen in nanoparticles containing immiscible elements, despite their synthesis is challenging due to the unfavorable thermodynamics. Here we show that silver nanoparticles doped with Co can be achieved by a facile one-step route relying on laser ablation in liquid. Structural analysis suggests that the bimetallic nanoparticles consist of a matrix of face-centred cubic Ag rich of cobalt as point defects or dislocations, in a structure that is stable over time even in aqueous solution. This happens despite the complete immiscibility of the two metals at any temperature in the solid and liquid phase, as confirmed also by density functional theory calculations. The nonequilibrium Co-Ag nanoparticles benefit of silver features such as the plasmonic response and the easy surface chemistry with thiolated ligands, combined with the magnetic properties of cobalt. Importantly, plasmonics and magnetism are not quenched after mixing, contrary to what was observed in other bimetallic systems like the Au-Fe one. This opens the way to several technologically relevant applications and, as a proof of concept, we demonstrate magnetophoretic assembly of Co-Ag nanoparticles into arrays of plasmonic dots exploitable for surface-enhanced Raman spectroscopy. [ABSTRACT FROM AUTHOR]

The stabilities evolution of capped and uncapped Ag NPs are highly relevant to the surface charged structure of Ag NPs in colloids. Understanding the stability evolution of the silver nanoparticles (Ag NPs) in colloid has great benefits for its controllable preparation, storage and application. Herein, uncapped Ag NPs with diameter of 1.66 ± 0.37 nm are obtained by laser ablation of Ag target in deionized water, corresponding surface plasma resonance (SPR) bands, ζ potential and particle size distribution are monitored to investigate uncapped Ag NPs' stability evolution. Due to negatively charged surface, uncapped Ag NPs show an excellent dispersion stability in 70 days without any external disturbance. But its dispersion stability and structure stability are destroyed easily by an oscillation treatment, resulting in a tardy growth and the formation of one-dimensional Ag nanochain. In addition, the chemical stability of uncapped Ag NPs is dramatically varied by a displacement reaction with an inserted copper wire. As comparison, two typical cationic and anionic surfactant molecules, N -hexadecyl trimethyl ammonium chloride (CTAC) and sodium dodecyl benzene sulfonate (SDBS) are severally used to prepare surface capped Ag NPs. With same treatment of Ag colloid, both two kinds of capped Ag NPs display better dispersion stability and structure stability than uncapped Ag NPs. Moreover, CTAC capped Ag NPs keep a better chemical stability than SDBS capped Ag NPs. [ABSTRACT FROM AUTHOR]

Antibacterial textiles, which effectively inhibit bacterial breeding and resist pathogenic diseases, have wide applications in medicine, hygiene, and related fields. However, traditional antibacterial textiles exhibit significant limitations, such as poor antibacterial durability and contamination during preparation. In this work, nanofiber yarn loaded with a high-efficiency antibacterial agent was prepared using electrospinning technology. Polyethyleneimine (PEI) was introduced as a solubilizing material to functionalize graphene oxide (GO) to form GO-PEI composites. A facile microwave heating method was used to synthesize GO-PEI and silver nanoparticles (AgNPs). A multi-needle conjugated electrospinning device was used to blend the nanofibers with the GO-PEI-Ag composite to form a nanofiber core-spun yarn. The antibacterial agent was firmly fixed on the fiber to prevent easy removal. A uniformly oriented yarn structure and internal morphology were observed, and the antibacterial activity of the fabric was measured. The antibacterial rate of the fabric was over 99.99% for both Escherichia coli and Staphylococcus aureus. After ten washes, the antibacterial rate remained above 99.99%. Thus, nanofiber fabric from electrospinning displays high antibacterial activity and excellent durability, thereby providing a feasible methodology for future production of antibacterial textiles. [ABSTRACT FROM AUTHOR]

In this study, we investigate the interactions between the cellulose surface and Ag nanoparticles (AgNPs) for the purpose of manufacturing hybrid nanomaterials using bacterial cellulose nanocrystals (BCNs) as a model substrate. We focus on the role of the BCN surface chemistry on the AgNP nucleation obtained by chemical reduction of Ag+ ions. Homogeneous hybrid suspensions of BCN/AgNP are produced, regardless of whether the BCNs are quasi-neutral, negatively (TBCNs) or positively charged (ABCNs). The characterization of BCN/AgNP hybrids identifies the –OH surface groups as nucleation points for AgNPs, of about 20 nm revealing that surface charges only improve the accessibility to OH groups. X-ray Absorption technics (XANES and EXAFS) revealed a high metallic Ag 0 content ranging from 88% to 97%. Moreover, the grafting of hydrophobic molecules on a BCN surface (HBCNs) does not prevent AgNP nucleation, illustrating the versatility of our method and the possibility to obtain bifunctional NPs. A H 2 O 2 redox post-treatment on the hybrid induces an increase in AgNPs size, up to 90 nm as well as a shape variation (i.e., triangular). In contrast, H 2 O 2 induces no size/shape variation for aggregated hybrids, emphasizing that the accessibility to –OH groups ensures the nucleation of bigger Ag nano-objects. [ABSTRACT FROM AUTHOR]

In this work, we have investigated the use of a heterogeneous catalyst based on reduced graphene oxide-grafted with carboxymethyl chitosan (rGO-CMCHT) and silver nanoparticles (AgNPs) for hydrogen generation through straightforward borohydride decomposition reaction. Thus, an rGO-CMCHT thin film containing AgNPs was successfully prepared by using a dip-coating technique. Characterization analysis indicated that rGO-CMCHT enhances the catalytic activity of AgNPs due to its intrinsic electric capacity (i.e., low electron-mobility resistivity). The experimental results showed that the prepared thin film has a remarkable catalytic activity that boosts hydrogen generation (maximum rate 180 × 102 mL min−1 g−1), achieving TOF values (480 min−1) that exceed the previously reported data. High TOF values were also obtained in aqueous and non-aqueous media using low amounts of catalyst, confirming its versatility. Reuse experiments demonstrated that thin film could be recycled and reused for at least ten consecutive reactions without losing catalytic efficiency. Spectroscopic analyses showed that AgNPs were not leached in the reaction medium after the reuse cycles, indicating that rGO-CMCHT stabilizes the nanoparticles efficiently. Finally, the prepared thin film also showed excellent catalytic performance catalytic towards the reduction of nitroaromatic compounds in aqueous and non-aqueous media, confirming its versatility for hydrogen production and hydrogenation reactions. [ABSTRACT FROM AUTHOR]

AgNPs loaded quaternized lignin (QAL) composites (Ag@QAL) were synthesized in-situ with the assistance of the microwave radiation with enhanced antibacterial activity. Lignin has been considered as a green carrier with excellent biocompatibility for the biomedical applications in drug release, tissue engineering, etc. In this study, silver nanoparticles (AgNPs) incorporated quaternized lignin (QAL) composites (Ag@QAL) were synthesized in-situ with the assistance of the microwave radiation. The positive charged QAL, not only serves as reductive and stabilizing carriers, but also endows with electrostatic effect toward negatively charged Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), resulting in greatly enhanced antibacterial activity. It is worth mentioning that Ag@QAL exhibits the highest antibacterial activity, which causes 3.72 log 10 (>99.9%) and 5.29 log 10 (>99.999%) CFU/ml reduction against E. coli and S. aureus respectively after contacting for only 5 min. Furthermore, due to the strong interaction between Ag@QAL and Ag+/AgNPs, bacteria can be captured and co-precipitated by Ag@QAL fastly in 30 min with almost none silver ions detected in the supernatant, which prevents Ag+ leaking with extremely low toxicity to the biological environment. This concept of electrostatic capture effect induced antibacterial activity enhancement and environmentally benign features may provide new insights into the design of highly effective antibacterial agents in a sustainable manner. [ABSTRACT FROM AUTHOR]

• Multifunctional fabrics was achieved by coating with AgNPs and polymers. • The EMI SE of the composite fabrics could reach ~112 dB. • The composite fabrics exhibited superhydrophobic performance. • The composite fabrics have good anti-corrosion and self-cleaning ability. • The composite fabrics had good antibacterial ability. Multifunctional cotton fabrics have attracted significant attention as next-generation wearable materials. Herein, we report a facile method for the fabrication of flexible and wearable cotton fabrics with ultra-high electromagnetic interference (EMI) shielding, antibacterial, and superhydrophobic properties. Cotton fabrics were first coated chemically with silver nanoparticles using polydopamine as adhesive and then with hydrophobic polydimethylsiloxane or polyimide. The introduction of polydopamine significantly increased the bond between silver nanoparticles and cotton fibers, thereby preventing silver nanoparticles from falling off the surface. The composite fabrics exhibited a high conductivity of ~1000 S/cm, and their EMI shielding effectiveness increased up to ~110 dB. The composite fabrics exhibited excellent self-cleaning performance and acid-alkali corrosion resistance because of their superhydrophobicity. Notably, the fabric composites showed a significant antibacterial action against Staphylococcus aureus and Escherichia coli. [ABSTRACT FROM AUTHOR]

The selective catalytic oxidation of cyclohexane has important theoretical and practical application value. However, high conversion rate and high selectivity are difficult to achieve simultaneously by conventional catalytic system. In this work, blue molybdenum trioxide (MoO 3) nanorods with oxygen vacancies were prepared by hydrothermal method using hydrated molybdic acid as a precursor under the reduction of formic acid, and in-situ produced MoO 3 -silver (MoO 3 -Ag) composites were further used in the photothermal catalytic oxidation of cyclohexane with high conversion and high selectivity using dry air as oxidant. The results showed that the best conversion rate of cyclohexanone and cyclohexanol (KA oil) could reach 8.6% with the selectivity of 99.0%. The excellent catalytic performance of MoO 3 -Ag composites can be attributed to the significantly increased visible and near-infrared light absorption caused by the plasma resonance effect of Ag nanoparticles and oxygen vacancies, and the prevented charge recombination by MoO 3 -Ag Schottky heterojunction. This work provides new reference solutions for the design and preparation of high-performance photothermal catalysts for the selective oxidation of hydrocarbons. [ABSTRACT FROM AUTHOR]

Functional textiles engineered for maintaining body comfort by fast sweat release using the directional moisture transport concept are in high demand. However, designing these functional textiles remains a critical job and generally requires multi-step complex fabrication routes. In this regard, developing one-step strategy to fabricate multi-scaled, inter-connected nonwoven-nanofiber/nets hierarchical fibrous composite membranes with asymmetric wettability for enhanced directional moisture transport would be a very fruitful approach. Composite membranes were fabricated by the rational combination of commercial polyethylene terephthalate nonwoven (CNW) as hydrophobic layer, and polyamide and silver nanoparticles (PA-Ag) nanofiber/nets as hydrophilic layer via one-step electrospinning process. The resultant CNW/PA-Ag nanofiber/net composite membranes were carefully investigated for water vapor transport, moisture management performance, and antibacterial activity. The subsequent membranes not only exhibit exceptionally high one-way moisture transport index (1253%), considerably high water vapor transport rate (11.45 Kg m-2d-1), and overall moisture management capacity (0.91), but also offer high resistance of 16.9 cm H 2 O to prohibit the moisture drive in the opposite way, and considerable antibacterial activity against Escherichia coli and Staphylococcus aureus. The effective one-step fabrication of such fascinating directional moisture transport membranes with decent antibacterial activity opens a new intuition into the designing of novel functional materials for rapid sweat release and personal drying applications. [ABSTRACT FROM AUTHOR]

Three step synthesis route to forming silver coated silica nanoparticles with citrate as a key ingredient to achieving morphological control. We describe the use of citrate to control the electroless plating of silver metal on silica nanoparticles. We find that the incorporation of relatively small amounts of citrate during the reduction of the Tollens' reagent in the presence of sensitized silica nanoparticles induces a continuous transition from conformal to raspberry particle coatings. This transition is dependent on both the citrate concentration and the silver precursor concentration. We characterize this transition using electron microscopy and spectroscopy and use these results to confirm citrate's ability to cap and restrict silver growth. We compliment these structural measurements with in-situ quartz crystal microbalance experiments to quantify citrate's role as a complexing agent to slow silver reduction kinetics. These results confirm citrate's dual role in controlling the morphology of silver deposits produced in this work. [ABSTRACT FROM AUTHOR]

Polymer additives such as Polyvinylpyrrolidone (PVP) are ubiquitously used in wet chemical reduction methods to tune nanoparticle sizes and shapes. However, all polymers retain some traces of their synthetic history through their end-groups and impurities. These impurities may thus impact redox and interfacial processes occurring during the formation of nanocolloids. We report a systematic comparison of four representative silver nanoparticle syntheses in the presence of either commercial PVP or its purified version, obtained through dialysis or filtration. We characterized the resulting nanoparticle dispersions through UV–visible spectroscopy, electron microscopy, X-ray scattering and Raman spectroscopy. For all syntheses and methods, the simple removal of PVP molecular impurities drastically modifies nanoparticle size, shape and formation kinetic. Impurities from additives thus play a pivotal role in nanoparticle syntheses and must be systematically evaluated for relevant mechanistic investigations and robust process engineering. [ABSTRACT FROM AUTHOR]

• Well-dispersed Ag NPs developed on Cu support assisted with in-situ electrochemical redox are fabricated. • The as-synthesized Ag NPs-based material shows superior catalytic activity and stability towards ORR. • The synergistic effect of electrochemical redox activation and NiII ions-mediation is discussed. • A novel activation path to boost the ORR catalytic activity of Ag-based electrocatalysts is proposed. • This work provides a general way to anchor metal NPs on supports uniformly and stably. Silver nanoparticles (NPs) developed on a copper substrate, Ag NPs/Cu, are synthesized by a novel and facile galvanic replacement method performed in Ethaline deep eutectic solvent (DES). It reveals that the Ag NPs could be well dispersed on the Cu support via an in-situ electrochemical oxidation-reduction (ECO-ECR) activation process, which deliver significantly enhanced activity and stability for the oxygen reduction reaction (ORR) in alkaline media. The in-situ redox tuning triggers a reversible phase transformation of the formed initially Ag NPs, Ag ↔ Ag 2 O, with surface reconstruction and gives rise to a strong metal-support interaction with tailored atomic/electronic structures, resulting in enhanced ORR activity. Impressively, the introduction of NiII ions can regulate the galvanic replacement kinetics by mediating the diffusion of AgI ions and subsequent growth of Ag on the Cu surface in Ethaline, leading to the formation of uniformly distributed Ag NPs. Coupled with redox activation, the optimal Ag-Ni 1 NPs/Cu_ECO-ECR exhibits ORR activity similar to that of the commercial state-of-the-art Pt/C catalyst, and better long-term durability (95% activity retention after 30,000 s), cyclic stability performance, and anti-poisoning capacity for methanol (96% after 3300 s), suggesting it a promising ORR electrocatalyst for practical application. [ABSTRACT FROM AUTHOR]