One-dimensional Silver Nanowires Research Articles

Flexible Dry Epidermal Electrophysiological Electrodes Based on One-Dimensional Platinum-Coated Silver Nanowires

Flexible Dry Epidermal Electrophysiological Electrodes Based on One-Dimensional Platinum-Coated Silver Nanowires

Achieving superior thermal conductivity in polymer bonded explosives using a preconstructed 3D graphene framework

When subjected to complicated thermal alternation, the low thermal conductivity (k) of polymerbonded explosives (PBXs) will induce high thermal stress, which will undermine the safety and reliability of the explosives by causing cracks or damage. However, it has been proven to be a challenge to efficiently increase the k of PBXs due to the high interfacial thermal resistance (ITR) and intrinsic defects of their conductive nanofillers. By introducing AgNWs with a high aspect ratio into graphene, this study constructed a novel multi-dimensional high-k nanofiller composed of one-dimensional (1D) silver nanowires (AgNWs) and two-dimensional (2D) graphene, namely gra@AgNWs. The AgNWs decorated could remedy the intrinsic defects of graphene by passing through the interspaces within graphene nanosheets to form connections as bridges. Consequently, the k of energetic polymer composites increased significantly by 89% from 0.425 ​W ​m−1 ​K−1 to 0.805 ​W ​m−1 ​K−1 at ultralow filler loading of 0.5 ​wt%. Furthermore, the temperature gradients and thermal stress in the composite cylinder decreased significantly under complicated thermal changes owing to the enhanced k. As quantitatively demonstrated through the fitting of experimental data using a theoretical model, AgNWs significantly decreased the ITR, paving highways” for phonon transfer between adjacent graphene nanosheets. Hence an expected synergistic effect of heat transfer was produced in the composites. This study provides new insights into the design and preparation of highly thermally conductive composites.

Ultrasensitive Strain Sensor Utilizing a AgF-AgNW Hybrid Nanocomposite for Breath Monitoring and Pulmonary Function Analysis.

Breath monitoring and pulmonary function analysis have been the prime focus of wearable smart sensors owing to the COVID-19 outbreak. Currently used lung function meters in hospitals are prone to spread the virus and can result in the transmission of the disease. Herein, we have reported the first-ever wearable patch-type strain sensor for enabling real-time lung function measurements (such as forced volume capacity (FVC) and forced expiratory volume (FEV) along with breath monitoring), which can avoid the spread of the virus. The noninvasive and highly sensitive strain sensor utilizes the synergistic effect of two-dimensional (2D) silver flakes (AgFs) and one-dimensional (1D) silver nanowires (AgNWs), where AgFs create multiple electron transmission paths and AgNWs generate percolation networks in the nanocomposite. The nanocomposite-based strain sensor possesses a high optimized conductivity of 7721 Sm-1 (and a maximum conductivity of 83,836 Sm-1), excellent stretchability (>1000%), and ultrasensitivity (GFs of 35 and 87 when stretched 0-20 and 20-50%, respectively), thus enabling reliable detection of small strains produced by the body during breathing and other motions. The sensor patching site was optimized to accurately discriminate between normal breathing, quick breathing, and deep breathing and analyze numerous pulmonary functions, including the respiratory rate, peak flow, FVC, and FEV. Finally, the observed measurements for different pulmonary functions were compared with a commercial peak flow meter and a spirometer, and a high correlation was observed, which highlights the practical feasibility of continuous respiratory monitoring and pulmonary function analysis.

AgNWs/MXene derived multifunctional knitted fabric capable of high electrothermal conversion efficiency, large strain and temperature sensing, and EMI shielding

Human thermal comfort management, motion capture and protection are highly needed in electronic wearable devices for their stretchability, wearing comfort, and versatility. Multifunctional smart textile becomes a favorable solution. Here, multifunctional electronic knitted fabric for strain sensing and thermal management is provided by a simple dip-coating process, involving the deposition of one-dimensional (1D) silver nanowires (AgNWs) and two-dimensional (2D) transition metal carbide/carbonitride (MXene) nanosheet. This multifunctional knitted fabric possesses excellent mechanical durability (>1000 cyclic stretching) and a wide strain sensing range limitation (~445%) comes from the high elastic knitted fabric. In addition, outstanding Joule heating (When the current is 0.10 A (A), the fabric can reach an equilibrium temperature of around 126 °C within 37 s, with a great electrothermal conversion efficiency hr+c of 0.13 and a maximum heating rate of 9.73 °C/s) and temperature sensing performance (temperature coefficient of resistance (TCR) of − 0.07%/°C) are achieved. Moreover, this smart fabric gives a high EMI shielding performance (44 dB). This work provides multifunctional AgNWs/MXene fabric using a simple dip-coating process for physical monitoring, wearable thermal management and other applications.

Boosting thermoelectric performance of BayCo4Sb12 by interlinking large-aspect-ratio silver nanowires at the triple junction of grain boundaries

Decoupling electrons and phonons transport has been a major challenge for enhancing thermoelectric (TE) performance. Incorporation of guest nano-inclusions into host phases has been proven effective for enhanced phonon scattering but induces additional electron scattering, resulting in limited effect in the improvement of TE performance. Herein, one-dimensional high-conducting silver nanowires (AgNWs) with a large aspect ratio have been uniformly incorporated into Ba0.2Co4Sb12 matrix. The AgNWs become Y shaped at the triple junctions of the grain boundaries, which create more hetero-interfaces for tuning the TE properties. The semi-coherent hetero-interfaces minimized the electron scattering, and the large-aspect-ratio AgNWs facilitate their interlinks, thus remarkably promoting the carrier mobility due to the reduction of boundary potential barrier. Meanwhile, the AgNWs could form nano-meso-micro-scale defects on random cross-sectional planes due to random penetration angles, bringing in full-wavelength phonon scattering. In a combined effect, a peak zT of 1.24 was achieved, enhanced by ∼43%. The corresponding TE module exhibited a high conversion efficiency of ∼8%, among the highest ever reported. This work demonstrated an effective strategy for enhancing TE performance by incorporating one-dimensional large aspect ratio conducting nanowires into the host phases with simultaneous reduction of thermal conductivity and enhancement of electron mobility.

Ultralow-Voltage-Drivable Artificial Muscles Based on a 3D Structure MXene-PEDOT:PSS/AgNWs Electrode.

The main challenge in manufacturing an ionic actuator of large bending displacement and great response sensitivity is to design a flexible electrode with great electrochemical characteristics and conductivity. This research reports the MXene-PEDOT:PSS/AgNWs (MPA) electrode with a three-dimensional (3D) network structure formed by a hybrid method of the one-dimensional (1D) silver nanowires (AgNWs) and the two-dimensional (2D) Ti3C2Tx MXene. Here, a soft actuator based on the ionic cross-linked hybrid electrode was designed. The results show that the MPA electrode-based soft actuator achieves a large bending strain (0.48%, ±0.5 V sine voltage), wide frequency (0.1-10 Hz), 5 h durability (91.9% retention), fast response time (≈5 s), great power density (7.53 kW m-3), and great energy density (18.83 kJ m-3). These excellent performances contribute to the 3D structure of electrodes formed by MXene and AgNWs creating an unhindered ion channel, which facilitates short diffusion and rapid injection of ions and provides higher capacitance and mechanical integrity. This 3D network layered structure hybrid electrode provides an opportunity for the development of ultralow-voltage-drivable artificial muscles.

Anti-Fogging, Frost-Resistant transparent and flexible silver Nanowire-Ti3C2Tx MXene based composite films for excellent electromagnetic interference shielding ability

The development of electronics proposes higher requirements for flexible, transparent, and conductive materials with high electromagnetic shielding performance in viewing windows. Flexible transparent films have been fabricated by collaborating one-dimensional silver nanowires (AgNWs) and novel two-dimensional Ti3C2Tx MXene sheets on PET films with an external polymeric coating consisting of poly (vinyl alcohol) (PVA) and poly(styrene sulfonate) (PSS). Especially, the combination of different dimensional nanomaterials effectively establishes a conductive network that exhibits a synergistic effect on excellent electromagnetic interference (EMI) shielding performance, which is superior to that of pure AgNW network or Ti3C2Tx network to some extent. By optimizing the AgNWs content (0.05 mg/cm2) and Ti3C2Tx sheets content (0.01 mg/cm2), the PET/AgNW/Ti3C2Tx/PVA-PSS film exhibits a transmittance of 81% and a desirable EMI SE value of 30.5 dB. In addition, the film shows outstanding anti-fogging and frost-resistant properties due to the remarkable water absorption capacity of PVA and PSS on the external surface. Considering its efficiency and simplicity, this transparent conductive film has promising applications in flexible transparent electronic devices and optical related fields.

Bacterial cellulose nanofiber triboelectric nanogenerator based on dielectric particles hybridized system

Triboelectric nanogenerators (TENGs) is an emerging method to convert mechanical energy into electricity, however, the complicated methods to improve the output performance greatly limited their potential applications. In this work, a simple and effective method was used to improve bacteria cellulose (BC) based TENG. The BC composite film friction material with a hybridized system of silver nanowires and BaTiO3 (BTO) particles was prepared by filtration method. One-dimensional silver nanowires particles and tetragonal phase BTO particles played an important role in improving the dielectric constant and surface roughness of the material respectively. With the combination of the enhancement of dielectric constant and the improvement of surface structure of the BC composite film, the short-circuit current of BC/AgNWs/BTO-based TENG was 7.1 μA, the open-circuit voltage was 87 V, and the transfer charge was 35 nC at a frequency of 3 Hz. In addition, when an external resistor was connected, the peak power density can reach 75 μW/cm2, and the overall TENG had good output stability. Moreover, the BC/AgNWs/BTO-based TENG can collect mechanical energy through human–machine movement when combined with a portable electronic device. This work demonstrates the great potential of cellulose-based materials in TENG and other electronic applications.

Construction of 3D MXene/Silver nanowires aerogels reinforced polymer composites for extraordinary electromagnetic interference shielding and thermal conductivity

The novel multifunctional materials with anti-electromagnetic interference (EMI) and effective thermal management are ideal for modern electronic industry. Generally, the EMI shielding effectiveness (SE) and thermal conductivity (TC) of materials can be effectively enhanced by compounding with high electrically and thermally conductive fillers. However, it seems that the high-performance cannot be compensated without sacrificing the high fillers loading. Herein, from one-dimensional silver nanowires (AgNWs) and two-dimensional MXene, three-dimensional MXene/AgNWs aerogels were designed as electric and heat transferring skeletons for epoxy nanocomposites by directional-freezing and freeze-drying methods. The resultant MXene/AgNWs/Epoxy nanocomposites with a low MXene/AgNWs content of 8.2 wt% combine a high electrical conductivity of 1532 S/m, and an exceptional EMI SE value of 94.1 dB with 3 mm thickness at the X-band frequency, as well as an improved TC of 2.34 W/m·K. The fabricated MXene/AgNWs/Epoxy nanocomposites possess excellent comprehensive properties enable valuable applications in electronic devices for EMI shielding and thermal management.

Epitaxial growth of one-dimensional different-diameter silver nanowires

With the increasing demand for higher-level functional nanodevices, there is a strong requirement for the fabrication of high-crystallinity composite nanowires, e.g., one-dimensional end-to-end different-diameter silver nanowires.

One-dimensional core-shell composite of AgNWs@Si@GO for high-specific capacity and high-safety anode materials of lithium-ion batteries

Si/C composite materials used for Lithium-ion battery anode, have received widespread attention owing to theirs superior energy density, long cycle life, and low self-discharge efficiency. However, the unstable solid electrolyte interface (SEI) and severe volume expansion, occurring in lithiation-delithiation of silicon materials, are major obstacles to its commercial application. Here, we proposed a silver nanowire@silicon@graphene oxide (AgNWs@Si@GO) core-shell structure by introducing one-dimensional silver nanowire into reactive silicon material through an uncomplicated polyol method. The electrochemical properties of the prepared AgNWs@Si@GO composites were well characterized as the anode of Lithium-ion batteries (LIBs). The synthesized AgNWs@Si@GO composites exhibited exceptional electrochemical performance, high specific capacity (1384.8 mA h/g at 0.2 C) and improved cycle stability. The excellent electrical conductivity of AgNWs and the outstanding flexibility of GO makes AgNWs@Si@GO core-shell structure efficaciously alleviate the volume expansion of silicon-based materials in the process of lithiation, and further improve the cycle stability of electrode materials.

Preparation of gold-decorated silver nanowires for improving conductivity of electrically conductive adhesives

Excellent electrical conductivity generally conflicts with high lap shear strength for electrically conductive adhesives (ECAs). One-dimensional silver nanowires (AgNWs) as conductive fillers can effectively solve the problem. However, insulating ligands on the nanowires will form a large contact resistance between the nanowires and limit the electrical conductivity of ECAs. In this work, we reported a one-step method to prepare Au-decorated AgNW conductive fillers. Through controlling the filler content, curing temperature, and curing time, the ECAs filled with Au-decorated AgNWs obtained exceptional electrical performance. When the filler content was 39 wt%, the resistivity reached to 7.8 × 10−5 Ω cm, which had a strong competitiveness to tin–lead solder. Therefore, the feature opens up possibilities for ECAs filled with the hybrid nanofiller to completely replace traditional solder.

A facile and economical process for high-performance and flexible transparent conductive film based on reduced graphene oxides and silver nanowires

The one-dimensional (1D) silver nanowires (AgNWs) with high transmittance, high electronic conductivity and two-dimensional (2D) reduced graphene oxide (rGO) both emerge as leading candidates for the development of next-generation transparent conductive films (TCFs). However, the relatively high sheet resistance of rGO and the poor corrosion resistance of AgNWs hinder them to fabricating TCFs independently in practical applications. Here, we used rGO bridging discrete AgNWs, improving conductivity and corrosion resistance of AgNW networks. In this work, firstly, graphene oxide (GO)/AgNW aqueous dispersions were prepared, in which GO played multiple roles as a dispersant to promote the stability of GO/AgNW aqueous dispersions as well. And then the rGO/AgNW hybrid films were successfully fabricated by a facile vacuum filtration followed by dry transfer to polyethylene (PE) substrates and subsequent reduction by hydroiodic acid (HI) vapor at 60 °C. The rGO/AgNW/PE TCF exhibited excellent optical and electrical properties (91.488% at 550 nm and 83.86 Ω/sq). The deposit density of rGO and AgNWs was merely 15.92 mg/m2 and 79.58 mg/m2, respectively.

Ultra-sensitive non-enzymatic amperometric glucose sensors based on silver nanowire/graphene hybrid three-dimensional nanostructures

Ultra-sensitive amperometric glucose sensors were developed by the synergistic combination of one-dimensional silver nanowires (Ag-NWs) and two-dimensional graphene sheets in the form of highly porous three-dimensional nano-structures (3D NSs). To achieve this, a simple hydrothermal sol-gel technique was applied by establishing covalent crosslinks. With a high specific surface area of 119.3 m2 g−1, the developed Ag-NW/graphene hybrid 3D NS-based glucose sensors exhibited a high sensitivity of 1249.1 µA mM−1 cm−2. To the best of our knowledge, this high sensitivity has not been achieved to date in the area of Ag/graphene hybrid-based glucose sensors. The results of this study will be an important step toward the development of electro-catalytic electrodes in bio-sensors.

Huge local magnetic field enhancement at optical frequencies in metamaterials through coupling with photonic band gap

We theoretically study the coupling of magnetic plasmon polaritons (MPPs) with photonic band gap (PBG) in a system composed of a one-dimensional (1D) silver nanowire pair array lying on a one-dimensional photonic crystal (1D PC). The near-field plasmon interactions in individual silver nanowire pairs induce MPPs. The 1D PC consisting of dielectric multilayer stacks with alternating refractive indices forms a PBG in the reflection spectrum. When the position of the PBG of the 1D PC is tuned to be close to the MPPs, the MPPs and the PBG can couple together to lead to a hybrid mode within the PBG. At the hybrid mode resonance, the magnetic fields in the center of Ag nanowire pairs are enhanced to nearly 4.3 times larger than those in the nanowire pair array directly lying on a substrate. Our numerical results hold important applications in magnetic sensors and magnetic nonlinearity.

Synergetic Effects of Silver Nanowires and Graphene Oxide on Thermal Conductivity of Epoxy Composites.

One-dimensional silver nanowires (AgNWs) and two-dimensional graphene oxide (GO) were combined to construct a three-dimensional network structure. The AgNWs can effectively inhibit stacking of adjacent GO sheets by occupying regions between layers of GO. Moreover, the GO sheets embedded in the gaps of the AgNWs network increase the interfacial contact area between the AgNWs and the epoxy matrix, resulting in the formation of more efficient phonon transport channels. To prepare an epoxy-based thermal conductive composite, hybrid networks were fabricated and added to epoxy resin using a solution mixing method. Significant synergistic effects were observed between the AgNWs and GO sheets. The thermal conductivity of epoxy composites filled with 10 wt.% AgNW/GO hybrids was found to be 1.2 W/mK and the impact strength was 28.85 KJ/m2, which are higher than the corresponding values of composites containing AgNWs or GO sheets alone. Thus, the thermal conductivity and impact strength of the epoxy composites were improved. The additive effects are mainly owing to the improved interfacial contact between the hybrid fillers and the epoxy resin, resulting in a more efficient phonon transport network. The use of hybrid fillers with different structures is a simple and scalable strategy for manufacturing high-performance thermally conductive materials for electronic packaging.

Stretchable strain sensor based on a nanocomposite of zinc stannate nanocubes and silver nanowires

In this study, we fabricated a stretchable strain sensor using a composite of three-dimensional zinc stannate (ZnSnO3) nanocubes (NCs) and one-dimensional silver nanowires (Ag-NWs) in a polydimethylsiloxane (PDMS) elastomer. The composite was spin-coated onto a polyethylene terephthalate (PET) substrate and was then peeled off after curing to obtain a thin film. The device performance was investigated at various mixing ratios (of the NCs and NWs in the PDMS elastomer). In order to evaluate the performance of the resulting devices, they were stretched to 100% of their original length. The sensor showed linear resistive behavior with high sensitivity, robustness, and repeatability, which are the key requirements for a stretchable sensor. The sensing mechanism of the sensor has been explained with emphasis on strain-induced separation of nanomaterials and percolation network.

Highly conductive 1D-2D composite film for skin-mountable strain sensor and stretchable triboelectric nanogenerator

The growing demand of intelligent wearable devices has triggered rapid development of highly stretchable strain sensors and power sources. Here, we fabricated a sandwich-structured stretchable device, where a composite film is encapsulated in two layers of polydimethylsiloxane (PDMS). The highly conductive composite film is composed of one-dimensional (1D) silver nanowires (AgNWs) network wrapped with two-dimensional (2D) metallic MoS2 nanosheets. The combination of 1D AgNWs and 2D metallic MoS2 nanosheets endows the composite film with excellent flexibility and conductivity, which enables their use as high-performance skin-mountable strain sensor with the maximum gauge factor of 215.4 and high stretchability up to 70%. Furthermore, the sandwich-structured device can serve as a stretchable triboelectric nanogenerator (STENG). Results show that the STENG with an area of 1 × 2.5 cm2 could produce an average power density of 0.16 W/m2. In addition, the STENG could retain stable output performance even under a stretching ratio of 50%. With the outstanding stretchability, it can be fully conformal on nonplanar irregular object such as plant leaves. Moreover, we demonstrated that the fabricated STENG could harvest wind energy and serve as a self-powered wind speed sensor when attached to plant leaves. This work provides new prospects for stretchable power sources and shows potential applications in wearable electronics.

Electrical and Mechanical Properties of Ink Printed Composite Electrodes on Plastic Substrates

Printed flexible electrodes with conductive inks have attracted much attention in wearable electronics, flexible displays, radio-frequency identification, etc. Conventional conductive inks contain large amount of polymer which would increase the electrical resistivity of as-printed electrodes and require high sintering temperature. Here, composite electrodes without cracks were printed on polyimide substrate using binder-free silver nanoparticle based inks with zero-dimensional (activated carbon), one-dimensional (silver nanowire and carbon nanotube) or two-dimensional (graphene) fillers. The effect of fillers on resistivity and flexibility of printed composite electrodes were evaluated. The graphene filler could reduce the resistivity of electrodes, reaching 1.7 × 10−7 Ω·m after low power laser sintering, while the silver nanowire filler improved their flexibility largely during bending tests. The microstructural changes were examined to understand the nanojoining process and their properties.

Silver Nanowires with Pristine Graphene Oxidation Barriers for Stable and High Performance Transparent Conductive Films

One-dimensional (1D) silver nanowires (AgNWs) have emerged as a leading candidate for the development of next-generation optoelectronic and wearable electronic devices. However, a key limitation of AgNW electrodes is that they are readily oxidized, resulting in a shift in properties leading to devices becoming erratic over time. To address this problem, we report a facile method to improve both the stability and performance of AgNW films. The AgNWs were combined with pristine graphene (pG) using an optimal (30/70 wt %) with the goals to prove that the pG sheets can provide a barrier shielding to protect against AgNW oxidation and have the additional benefit of improving the connections between wires and stability of the films. The fabrication of these films was demonstrated on wide range of substrates including glass, plastic, textile, and paper. A surface resistance of 18.23 Ω/sq and an optical transparency of 89% were obtained on the glass substrates, 50 Ω/sq and 88% transparency for poly(ethylene terep...