Conductive Layer Research Articles

Recyclable and Healable Electro‐Optical Fiber for Sensing and Information Transmission

AbstractElectro‐optical fibers with dual‐mode sensing ability show broad potential in wearable electronics and intelligent human‐machine interaction. However, the complex multi‐step preparation procedures and the limited environmental adaptivity in materials (stretchability, healability, recyclability, etc.) hinder its practical applications. Herein, based on a urea‐oxime polyurethane, a fiber integrating dual‐mode electrical sensing and two‐color light‐emitting functions is developed using a one‐step continuous coaxial wet‐spinning process, with luminescent sulfides‐doped shell layer and an ionogel conductive core layer. The fiber exhibits excellent mechanical, electrical, and optical healing capabilities with efficiencies of 94%, 92%, and 99%, which can be quickly recycled within 30 minutes. Utilizing the electro‐optical bimodular perceptive fiber, multi‐scenario applications including insect phototaxis monitoring, luminous wearables, and smart tripwires are demonstrated, revealing the healing superiority in programming complex fiber architectures to adapt to substrates with shape or size diversity. Moreover, a healing‐programmed fiber with tailored segments is demonstrated for electro‐optical hybrid encrypted information transmission. This work inspires a promising healing‐programming strategy of healable electro‐optical fibers for wide applications in tactile sensing and information communicating.

Mechanically Robust 3D Flexible Electrodes via Embedding Conductive Nanomaterials in the Surface of Polymer Networks.

3D flexible electrodes are essential to implement flexible pressure sensors in various flexible electronic applications. Conventional methods for fabricating these electrodes include electroless deposition, spray coating, and incorporating conductive nanomaterials into a polymer matrix. However, the electrodes fabricated using these methods are characterized by poor adhesion between the conductive layer and polymer surface and fail to maintain intrinsic mechanical properties of the polymer, such as elastic modulus and ductility. Herein, a transfer method in which conductive nanomaterials are embedded into the surface of polymer networks via optimal surface energy control is proposed, such as reducing adhesion between the mold and nanomaterials. This method induces mechanical interlocking between the surface of polymer networks and conductive nanomaterials, firmly anchoring them onto the polymer network surface. Moreover, the intrinsic mechanical properties of the fabricated 3D flexible electrodes remain unchanged. Flexible capacitive sensors prepared using the resulting electrodes exhibit a stable sensing performance (ΔC0,5000/C0 = 0.169%) even under repetitive pressure conditions (5000 cycles at 70kPa). The proposed robust 3D flexible electrode fabrication method presents a promising strategy for the future development of flexible pressure sensors.

Novel Cellulosic Fiber Composites with Integrated Multi-Band Electromagnetic Interference Shielding and Energy Storage Functionalities

In an era where technological advancement and sustainability converge, developing renewable materials with multifunctional integration is increasingly in demand. This study filled a crucial gap by integrating energy storage, multi-band electromagnetic interference (EMI) shielding, and structural design into bio-based materials. Specifically, conductive polymer layers were formed within the 2,2,6,6-tetramethylpiperidine-1-oxide (TEMPO)-oxidized cellulose fiber skeleton, where a mild TEMPO-mediated oxidation system was applied to endow it with abundant macropores that could be utilized as active sites (specific surface area of 105.6 m2g-1). Benefiting from the special hierarchical porous structure of the material, the constructed cellulose fiber-derived composites can realize high areal-specific capacitance of 12.44 F cm-2 at 5mAcm-2 and areal energy density of 3.99 mWh cm-2 (2005 mW cm-2) with an excellent stability of maintaining 90.23% after 10,000 cycles at 50mAcm-2. Meanwhile, the composites showed a high electrical conductivity of 877.19 S m-1 and excellent EMI efficiency (> 99.99%) in multiple wavelength bands. The composite material's EMI values exceed 100dB across the L, S, C, and X bands, effectively shielding electromagnetic waves in daily life. The proposed strategy paves the way for utilizing bio-based materials in applications like energy storage and EMI shielding, contributing to a more sustainable future.

Love Wave Modeling in Functionally Graded Composition of Conductive Polymers Layer and Piezoelectric Substrate Under Impulsive Point Source

Love Wave Modeling in Functionally Graded Composition of Conductive Polymers Layer and Piezoelectric Substrate Under Impulsive Point Source

Patterning Adhesive Layers for Array Electrodes via Electrochemically Grafted Polymers.

Electrophysiological sensors (electrodes) are used to collect complex electrophysiological signals, providing extensive information about the body's condition. Reliable signal acquisition necessitates stable skin-electrode interfaces to prevent adverse effects arising from interface variations. Although the incorporation of conductive adhesive layers can improve the stability of these interfaces, in array electrodes, the layer may also cause short circuits and signal crosstalk. Here, we propose a general strategy for patterning the adhesive layer of array electrodes based on electrochemically grafted adhesive polymers (EGAPs). Utilizing the conductivity differences between the sensing sites and the substrate material of flexible electrodes, spatial selective loading of adhesive and ionically conductive polymers can be achieved through in situ electrochemical reactions, thus realizing spontaneous patterning. This EGAP-based method allows for a rapid and selective electrode surface modification in just two steps. Furthermore, array electrodes with EGAP acquired stable electrophysiological signals while improving the stability of the skin-electrode interface and the quality of signal collected and effectively avoided signal crosstalk between arrayed sensing sites.

Regulation of Zinc Deposition by In Situ Formed Liquid Metal Interface for Dendrite‐Free Zinc Metal Anodes

AbstractUncontrolled dendrite growth, hydrogen evolution and corrosion challenges associated with zinc (Zn) anodes significantly restrict the practical application of zinc batteries. Herein, a liquid metal gallium (Ga) interface is in situ formed on carbon paper (CP) by electrochemical co‐deposition to construct a dendrite‐free Zn‐Ga@CP composite electrode which can regulate the transport and chemistry of Zn deposition at the electrode/electrolyte interface. Notably, the concurrent reduction of Zn2+ and Ga3+ on carbon paper results in the formation of a self‐supporting Zn electrode with 3D interpenetrating structure of Zn and Ga. Compared to zinc foil electrodes, the highly conductive liquid Ga layer lowers the nucleation energy barrier of Zn promotes the homogeneity of the electric field and ion flux, and induces uniform deposition of Zn. In addition, the low chemical activity of liquid Ga prevents a high rate of hydrogen evolution reaction and associated parasitic reactions. As a result, the Zn‐Ga@CP symmetric cell delivers stable cycling of >350 h at a discharge depth of 23.3% and ultra‐low voltage hysteresis. Moreover, the coin‐type and pouch‐type full cells exhibit excellent durability and good mechanical stability. This work provides a novel interface regulation strategy for achieving high‐performance dendrite‐free anode in Zn metal batteries.

Texturing (002)‐Oriented Zinc atop a Cotton Cloth for High‐Performance Zn‐ion Batteries

Zn‐ion batteries emerge as a promising alternative to conventional Li‐ion batteries, owing to their superior environmental friendliness and high safety for sustainable energy storage in various applications. However, there are still concerns about the limitations of Zn‐ion batteries, such as uncontrolled dendrite growth and side reactions. In this study, the electroplating method was employed to deposit (002) plane‐dominated textures on the modified cotton cloth substrate, which comprises a silver conductive layer atop the cotton supporting layer. The electroplating current density and time are critical for the fabrication of dense and compact (002) Zn textures. In this case, the optimized condition involves a current density of 40 mA/cm2 and the electroplating time of 30 minutes. Compared to (101)‐dominated Zn anodes, the (002)‐dominated electrode demonstrates faster deposition kinetic and lower charge‐transfer resistance, enabling the dense and uniform Zn deposition. Additionally, the (002)‐dominated electrode also depicts enhanced capability to inhibit the side reactions in the mild aqueous electrolyte, further strengthening the lifespan of Zn‐ion batteries. This work demonstrates the feasibility of employing ordinary cotton cloth as a substrate for electroplating (002)‐dominated Zn, thereby expanding the potential application of Zn‐ion batteries.

Hydrophobic PU fabric with synergistic conductive networks for boosted high sensitivity, wide linear-range wearable strain sensor

Strain sensing fabrics are able to sense the deformation of the outside world, bringing more accurate and real-time monitoring and feedback to users. However, due to the lack of clear sensing mechanism for high sensitivity and high linearity carbon matrix composites, the preparation of high performance strain sensing fabric weaving is still a major challenge. Here, an elastic polyurethane (PU)-based conductive fabric (GCPU) with high sensitivity, high linearity and good hydrophobicity is prepared by a novel synergistic conductive network strategy. The GCPU fabric consists of graphene sheets (GS)/carbon nanotubes (CNTs) elastic conductive layer and a PU elastic substrate. GS and CNTs can be constructed into a synergistic conductive network, and the fabric is endowed with high conductivity (1.193 S m-1). Simulated equivalent circuits show that GS in the conductive network will break violently under applied strain, making the GCPU fabric extremely sensitive (gauge factor 102). CNTs are spatially distributed in GS lamellae, avoiding the phenomenon that the constructed synergistic conductive network is violently fractured under the applied strain, which leads to the decrease of linearity (0.996). Styrene-ethylene-butylene-styrene (SEBS) was used as a dispersant and binder to uniformly disperse and closely bond GS and CNTs into PU fabrics. In addition, the hydrophobicity of SEBS makes the GCPU fabric resistant to water environment (The contact angle is 123°). Due to the good mechanical stability of GCPU fabric, GCPU fabric has a wide strain range (0%-50%) and high cycle stability (over 1000 cycles). In practice, GCPU fabric can accurately simulate and detect the size and deformation motion of human body. Therefore, the successful construction of elastic fabrics with synergistic conductive networks provides a feasible path for the design and manufacture of wearable intelligent fabrics.

Polycalmagite Coating Enables Long-Term Alkaline Seawater Oxidation Over NiFe Layered Double Hydroxide.

Renewable energy-powered seawater electrolysis is a green and attractive technique for producing high-purity hydrogen. However, severe chlorideions (Cl-) and their derivatives tend to corrode anodic catalysts at ampere-level current densities and hinder the application of seawater-to-H2 systems. Herein, a polycalmagite (PCM)-coated NiFe layered double hydroxide is presented on Ni foam (NiFe LDH@PCM/NF) that exhibits exceptional stability in alkaline seawater. PCM not only acts as a conductive layer to reduce charge transfer resistance of the anodes but also as a polymer-based protective layer to inhibit Cl- adsorption and stabilize metal ions oxidation due to its own anions and strong adhesion, thereby increasing activity and stability during alkaline seawater. Thus, NiFe LDH@PCM/NF only needs a low overpotential of 364 mV to reach up to 1000 mA cm-2 and maintains operation for 500 h without activity degradation. Moreover, a minimal amount of hypochlorite can be detected in electrolyte after a 500-h stability test. This development affords a significant exploration in creating durable and efficient anodes, highlighting the importance of polymer coating toward anti-corrosion in alkaline seawater oxidation.

A Robust Dual-Layered Solid Electrolyte Interphase Enabled by Cation Specific Adsorption-Induced Built-In Electrostatic Field for Long-Cycling Solid-State Lithium Metal Batteries.

Solid-state lithium (Li) metal batteries (SSLMBs) are considered as one of the most promising next-generation battery technologies due to their high energy density and intrinsic safety. However, interfacial issues such as side reactions and Li dendrite growth severely hinder the practical application of SSLMBs. In this contribution, we proposed a cationic built-in electrostatic field to drive the generation of an anion-derived dual-layered solid electrolyte interphase (SEI). The specific adsorption of tributylmethyl-phosphonium bis(trifluoromethanesulfonyl)imide (TMPB) cations onto negatively charged Li anode surface significantly prevents interfacial side reactions between vulnerable polyethylene oxide (PEO) and Li metal. More importantly, the formed cationic built-in electrostatic field induces the targeted trapping of Li-salt anions onto the Li metal surface, leading to the generation of an anion-derived dual-layered SEI, composed of a mechanically flexible organic-rich surface layer and a Li-ion conductive inorganic-rich bottom layer. As a result, the Li||Li cell demonstrated an extended lifespan of over 1900 hours with the reduced polarization voltage. The Li||LiFePO4 full cell also exhibited excellent cycling stability, maintaining an average Coulombic efficiency of 99.69% over 200 cycles at 0.5 C. This work provides valuable insights into mitigating interfacial degradation and promoting uniform Li deposition through surface electrostatic field regulation.

Graded Junction ZnO on rGO Conduction Layer for Ultraselective Cu(II) Ion Detection

Graded Junction ZnO on rGO Conduction Layer for Ultraselective Cu(II) Ion Detection

Damp‐Heat–Induced Degradation of Lightweight Silicon Heterojunction Solar Modules With Different Transparent Conductive Oxide Layers

ABSTRACTLightweight photovoltaic applications are essential for diversifying the solar energy supply. This opens up vast new scenarios for solar modules and significantly boosts the capacity of renewable energy. To ensure high efficiency and stability of the solar modules, several challenges need to be overcome. Degradation due to elevated temperature and/or humidity is a critical concern for silicon heterojunction (SHJ) solar modules. Here, we investigated the stability and degradation mechanism of encapsulated cells with lightweight configurations where the cells are based on three different types of transparent‐conductive oxide (TCO): indium tin oxide (ITO), aluminum‐doped zinc oxide (AZO), and a combination of ITO/AZO/ITO under humid and thermal environmental conditions. A damp heat (DH) test at a temperature of 85°C and relative humidity (RH) of 85% was performed on lightweight modules for 1000 h. Our results show that AZO is the most susceptible to DH degradation. The AZO film was damaged by the combined effects of moisture ingress and delamination of the interconnection foil, resulting in a decrease in the conductivity of the AZO film, leading to a dramatic increase in Rs and a decrease in FF of the modules. Consequently, moisture has a greater chance of percolating through the damaged AZO layer into the a‐Si:H passivation layer, causing passivation degradation, which leads to an increase in recombination, resulting in a decrease in Voc of the modules. In particular, after capping the AZO film with an ITO film, the efficiency loss of the ITO/AZO/ITO module was significantly reduced. This suggests that the ITO film could be a promising protective capping layer for the AZO‐based solar cells.

A PDMS/chitosan/MPMs composite film based on multi-field coupling enhancement for African swine fever virus P72 protein detection.

African swine fever (ASF) is an acute hemorrhagic disease in pigs caused by the African swine fever virus (ASFV), which has a high mortality rate and brought great damage to global pig farming industry. At present, there is no effective treatment or vaccine to combat ASFV infection, so early detection of ASFV has become particularly important. Therefore, the PDMS/chitosan/MPMs composite film was proposed to detect ASFV P72. PDMS mixed with chitosan particles were used to provide biological modification sites for the ASFV P72 antibody, which simplified the functional modification process. The specific binding of antigen and antibody leads to the mechanical deformation of the composite film, which was observedthrough optical method tochange the microsphere spacing. The polystyrene microsphere (PMs) spacing changes were acquired by simply measuring the diameters of the Debye ring diffracted by the PDMS/chitosan/PMs with a simple laser pointer. The conductive layer formed by AgNWs realize the transformation of biological signals to electrical signals. By conjugating PMs with Fe3O4 nanoparticles (MPMs) and applying a magnetic field, a magnetic-stress-electric coupling system has been constructed, which amplifies the deformation of the composite film and enhances the sensitivity of the flexible film. The experimental results showed that the flexible film has wide linear range of 10ng/mL-100μg/mL, and the optimal detection limit (LOD) is 0.059ng/mL, which was aboutone order of magnitude lower than that without magnetic field. In addition, the flexible film showed a good stability, specificity, and selectivity.

Stretchable, Self-Healable, and Durable Conductive Elastomer Derived from a Rationally Designed Covalently Cross-Linked Network.

Silver nanowire (Ag NW)-based elastic conductors have been considered a promising candidate for key stretchable electrodes in wearable devices. However, the weak interface interaction of Ag NWs and elastic substrates leads to poor durability of electronic devices. For everyday usage, an additional self-healing ability is required to resist scratching and damage. Therefore, robust Ag NW-based elastic conductors possessing stretchability, self-healing, and stability are highly desirable and challenging. Here, we present a universal interface tailoring strategy that introduces thiols onto the dynamically cross-linked elastic substrate surface. The surface thiol groups strongly interact with Ag NWs through Ag-S bonds, forming the stable conductive layer on the elastic substrate. At elevated temperatures, the Ag NWs are partially embedded in the surface of the elastic substrate and a buffer layer is formed to release the concentrated stress. As a result, the formed Ag NW-based elastic conductor displays the combination of good conductivity, high stretchability (>1000%), efficient self-healing capability (>95%), and remarkable stability. Besides, the Ag NW-based elastic conductor combining the good properties mentioned above is suitable for fabricating a sensitive and durable strain sensor against cyclic strain. The presented strategy can be considered a versatile and effective route to generating other surface thiol-rich covalently cross-linked elastomers with dynamic disulfide bonds.

Enhanced stability of microwave absorption in island-bridge structured organohydrogels.

Stretchable microwave absorbers (SMAs) are vital for flexible electronics. Traditional SMAs display unstable tensile properties resulting from inconsistencies between the constrained conductive layer and the flexible dielectric layer. This study introduces an organohydrogel-based stretchable microwave absorber (OSMA) that incorporates an organohydrogel within an island-bridge structure. Leveraging standing wave and field concentration effects, along with strain dissipation, the OMSA achieves 90% absorption in the 5-18 GHz range and maintains stable broadband absorption under a 30% uniaxial stretch, exhibiting tunable absorption and angular performance under transverse electric/magnetic (TE/TM) polarization. This approach offers a versatile, customizable, and cost-effective solution for SMAs.

Electrochemical Monitoring of Vitamins B9 and C in Environmental Matrices with an Oligo Diaminotriazole Electrode.

Chemical polymerization/oligomerization opens numerous opportunities, from fundamental materials research to practical applications in catalysis, energy, sensing, and medicine. The electrochemical detection of vitamins B9 (folic acid) and C (ascorbic acid) requires new approaches because of low selectivity, electrode fouling, and interference from other chemicals. As an excellent material for long-term vitamin detection, oligo 3,5-diamino-1,2,4-triazole (oligo DAT) enhances the sensitivity, selectivity, and stability of sensors by creating a stable, conductive layer that facilitates electron transfer and reduces interference from common substances like glucose or uric acid. This work investigates the electrochemical sensing properties of oligo DAT, utilizing hydrogen tetrachloroaurate (III) (HAuCl4) as an oxidizing agent at ambient temperature for the concurrent and sensitive detection of vitamins B9 and C. The oligo DAT was carefully characterized by spectroscopic and microscopic techniques to confirm its structure and properties. The GC electrode was subsequently connected to the oligo DAT by a potentiodynamic technique. The oligo DAT-modified electrode exhibited higher catalytic activity than the unmodified GC electrode for the oxidation of vitamins B9 and C. This led to the determination of the sensitivity levels for both vitamins; the lowest measured concentration for vitamin C was 1 × 10-11 M with a theoretical limit of detection (LOD) of 1.9 × 10-11 M, and for vitamin B9, the lowest measured concentration was 1 × 10-11 M with a theoretical LOD of 3.5 × 10-11 M. The practical efficacy of this straightforward method was proven by the quantification of vitamins B9 and C in human plasma samples.

Construction of three-dimensional conductive network layer by graphene and vanadium oxide composite for high performance long life low temperature aqueous zinc ion batteries

Construction of three-dimensional conductive network layer by graphene and vanadium oxide composite for high performance long life low temperature aqueous zinc ion batteries

Improved adhesion of printed Ag electrodes for flexible transparent display applications

This study presents an inkjet-printed, single-step double layer electrode with an acrylate adhesion layer on PES to enhance Ag adhesion. The electrode offers strong mechanical stability and a simplified solution for flexible device applications.

An active-conductive layer stacked sensor platform for real-time detection of heavy metal ions

The development of electrochemical sensors with high sensitivity and accuracy is crucial for the detection of low-concentration heavy metal ions (HMIs) such as Pb(II) and Hg(II), which remains challenging. To address this issue, MgFe-layered double hydroxide (MgFe-LDH) is synthesized as an active layer on the conductive layer SnO2 loaded with nickel foam (NF) with the assistance of oxygen vacancies (OVs) to form an active-conductive layer stacked sensor. The results show that MgFe-LDH@SnO2/NF exhibits superior sensitivity (Pb(II): 417 μA/μM; Hg(II): 986 μA/μM), wider linear range (1.1–2.2 μM) and lower limits of detection (Pb(II): 1.21 nM; Hg(II): 3.7 nM). The high performance of our sensor is attributed to the improved ability to adsorb HMIs via OV reduced binding energy as well as the promoted rapid electron transport via SnO2 reduced charge transfer resistance, as evidenced by density functional theory and electrochemical measurements. Particularly, by combining the newly proposed tiny electrochemical detection network (ECDNet-tiny) and WeChat mini program, we have built a real-time detection platform for Pb(II) and Hg(II) pollution categories and concentrations, which shows high accuracy (0.98) and recovery rate (91.6 %-106.8 %) in the detection of actual water samples. The qualitative and quantitative calculations of electrochemistry is innovatively implemented by deep learning. Besides, smartphones could display detection results transmitted from cloud servers. Thus, this work provides a new sensor platform to improve the sensitivity, accuracy, and intelligence of detecting quintessential HMIs.

Laser assisted solid doping promotes the formation of conductive layer on the surface of single-crystal diamond

Laser assisted solid doping promotes the formation of conductive layer on the surface of single-crystal diamond