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Abstract Silver nanoparticle (AgNP)/carbon nanotube (CNT) composites are drawing increasing attention for several applications, especially where transparency is required. However, interfacial interaction and stability of the AgNP/CNT composites have been scarcely investigated. In the present study, transparent coatings were prepared from dispersed AgNP-coated multiwalled CNTs and exposed to different sintering conditions. The changes in surface morphology and evolution of interfacial configuration of AgNP-decorated CNT transparent composite films were investigated. Under certain conditions, CNT ropes were glued to one another by the melted AgNP aggregates, resulting in the improvement of the measured electrical properties. The in situ measurements of the electrical properties allowed correlating the AgNPs sintering mechanism with the morphological observations. Notably, at a given temperature, increasing the initial film density increased the time necessary to complete the AgNPs sintering. The obtained results show that the electrical resistance can be used as a tool to indirectly monitor the network state of transparent AgNP-decorated CNT composite films, hence paving the way to tuning the composite film properties with a high precision for the desired application. These findings also explain the mechanism of reinforcement of polymer nanocomposites by the current nanofillers. [ABSTRACT FROM AUTHOR]

Abstract Flexible and transparent substrate materials were fabricated by using bacterial cellulose (BC), silk fibroin protein (SF) and/or polyvinyl alcohol (PVA). The BC-SF and BC-SF-PVA films obtained were further modified by impregnation with silver nanocubes (AgNC). The influences of the silver nanocubes and white light illumination on the electric and viscoelastic properties of the films were investigated. Complex conductivity measurements showed that the films with PVA component are more sensitive to light exposure and there is an increase in conductance when the sample is illuminated. The films that contained silver nanocubes showed higher values of specific susceptance than their unmodified counterparts. DMA analyses revealed that the storage shear moduli of the films increase with addition of silver nanocubes. It was also found that the relaxation transition observed at elevated temperatures in the BC-SF-PVA-AgNC films is highly sensitive to the light exposure. Above the glass transition of PVA, both storage- and loss-shear moduli change dramatically if the sample is illuminated during the measurements with respect to the case when it was kept in the dark. Highlights • Flexible transparent bacterial cellulose-silk fibroin-PVA films were prepared. • Impregnation with nanostructured silver affects the physical properties of the film. • The effects of the illumination on the properties of the films were studied. • High-temperature mechanical transition of the films is sensitive to light exposure. [ABSTRACT FROM AUTHOR]

Continuous silver shells were deposited on copper flakes using a two-stage precipitation process. A tightly packed layer of silver nanoparticles was first formed on the surface of the base metal by galvanic displacement. The size of the noble metal particles and their distribution on the substrate were controlled using complexing agents and dispersants. A continuous Ag deposit was subsequently grown by reducing slowly [Ag(NH 3 ) 2 ] + ions with glucose. The final shell thickness was controlled by varying the amount of metal deposited in the second step. The electrical properties of resulting silver coated copper flakes are comparable to those measured for silver flakes of similar size and aspect ratio. By preventing the oxidation of copper cores up to 400 °C, the hermetic noble metal shell dramatically extends the temperature range in which Ag/Cu flakes can successfully replace pure silver. [ABSTRACT FROM AUTHOR]

Silver nanowire-based flexible transparent electrodes have critical problem, in spite of their excellent electrical and optical properties, that the electrical conductance and transparency degrade within several days in air because of oxidation of silver. To prevent the degradation of the silver nanowire, we encapsulated Ag-NWs with thin TiO barrier. Bar-coated silver nanowires on flexible polymer substrate were laminated at 120 °C, followed by atomic layer deposition of TiO nanoshell. With 20 nm of TiO nanoshells on silver nanowires, the transparent electrode keeps its electrical and optical properties over 2 months. Moreover, the TiO-encapsulated silver nanowire-based transparent electrodes exhibit excellent bending durability. [ABSTRACT FROM AUTHOR]

In this paper, fully inkjet printed multilayer capacitors and inductors are fabricated and characterized using poly 4-vinylphenol (PVP) ink as the dielectric layer and silver nanoparticle ink as the conductor. Inkjet printed through vias, created with a novel dissolving method are used to make RF structures in a multilayer inkjet printing process. The vias have been realized in a 350-nm PVP film and exhibit resistance better than 0.1 $\Omega $ . Spiral inductors from 10 to 75 nH have been realized with maximum quality factors around five. The 10-nH inductor exhibits a self-resonant frequency slightly below 1 GHz. Metal–insulator–metal capacitors are realized with densities of 50 pF/mm ^{2} . These capacitors demonstrate values ranging from 16 to 50 pF. The 16-pF capacitor shows a self-resonant frequency over 1.5 GHz. The successful implementation of inductors and capacitors in an all inkjet printed multilayer process with vias is an important step toward fully inkjet-printed large area and flexible RF systems. [ABSTRACT FROM AUTHOR]

Silver nanowires have drawn remarkable attention owing to their anisotropic electrical and optical properties that differ from those observed in the bulk materials and the interesting applications in various areas such as electronic devices, chemical sensors and photonics. In this paper, silver nanowires with an average diameter of 450 nm and a length of up to 100 μm were successfully synthesized by a polyol process. The experimental results indicate that the morphologies and sintering behaviors of silver nanowires are impacted by glutaric acid and the sintering temperature. The isotropically conductive adhesives (ICAs) were made by adding silver nanowires to the polymer composites consisted mainly of epoxy resin, cure agent and catalyst, and then the electrical properties were investigated based on those physical parameters such like the fraction of the silver nanowires of the total of silver fillers and the curing temperature. The in situ monitoring of the variation in electrical resistance of the ICAs and DSC explore that silver nanowires can affect the curing behavior of the ICAs. Silver nanowires can significantly improve the electrical conductivity of the ICAs when the loading of silver nanowires is low and the curing temperature is less than about 250 °C. There is little difference of the electrical resistivity between the ICAs filled with silver nanowires and micro-sized silver flakes when the loading of silver fillers in the ICAs is 75 wt%, and this phenomenon is related to the curing temperature. The silver nanowires treated by glutaric acid can improve the electrical property of the ICAs. [ABSTRACT FROM AUTHOR]

Nanoparticle-based flexible field-effect transistors (FETs) containing carbon nanotubes (CNTs) and silicon nanowires (SiNWs) have attracted tremendous attention, since their interesting device performance can be utilized for integrated nanoscale electronics. However, use of CNTs and SiNWs on polymer substrates poses serious limitations in terms of their fabrication procedure, repeatability, and biodegradability. In this article, we report for the first time the fabrication and characteristics of solution-processed FETs on a paper substrate doped with easily prepared silver nanoparticles (AgNPs). To compare the FET performance, we fabricated two other FETs on paper containing ionic liquid (IL, 1-butyl-3-methylimidazolium octyl sulfate) and reduced graphene oxide (rGO) as dopants. We observe that the AgNP-based dopant generated good FET characteristics in terms of linear transconductance variations and higher carrier concentration values, showing negligible changes after bending and aging. In comparison with the AgNP-FET, the rGO- and IL-based dopants yielded high carrier mobilities, but the rGO-based FET is more susceptible to aging and bending. The excellent linearity of the I- V curve found for the AgNP-FET ensures its applicability for devices requiring linear transfer characteristics such as linear amplifiers. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been synthesized using maltose as reducing agent and microwave heating as reaction initiator. The nanoparticles are studied for their optical, structural, thermal, zeta potential and electrical properties. The synthesis protocol used is fast and resulted in the formation of multi-shaped AgNPs as indicated by their optical response and TEM. The crystallite size of nanoparticles and strain of the sample was found to be around 39 nm, and 2.3 × 10, respectively, as calculated from XRD data. Zeta potential and electrical response both showed almost threefold increase for multi-shaped as compared to isotropic nanoparticles. [ABSTRACT FROM AUTHOR]

The electrical explosion of wires was used to prepare titanium dioxide nanopowders alloyed with silver nanoparticles. The photoelectrochemical properties and electronic structure of these materials were studied. The quantum yield for the photoelectrochemical current η and the flat band potential E for TiO/Ag films were found to be proportional to the content of the Ag phase on the electrode surface. [ABSTRACT FROM AUTHOR]