Application Of Electrode Research Articles

Application of superhydrophobic Ti3C2 Mxene-based screen-printed ion-selective electrode for determination of Ca2+ concentration

Ti3C2 Mxene is a remarkable electrochemical material owing to its high conductivity, large specific surface area, and high electrical capacity. It can be applied in all-solid-state ion-selective electrodes to improve the ion-electron conversion efficiency and reduce the resistance. However, Ti3C2 Mxene is hydrophilic, which will form a water layer between the ion-selective membrane and the substrate, resulting in response potential drift. In this study, Ti3C2 Mxene functionalized with octadecyltrichlorosilane was developed as the ion-electron conversion layer (solid contact layer), and a polymer membrane containing N, N, N', N' -Tetracyclohexyl-3-oxapentanediamide was used as the Ca2+ selective membrane on a screen-printed electrode substrate. An all-solid Ca2+-selective electrode (SPE/SH-Ti3C2/Ca-ISM) was prepared. The results from cyclic voltammetry and electrochemical impedance spectroscopy proved the high capacitance and fast charge transfer ability of the Ti3C2 Mxene modified electrode. In addition, it shows good performance in the water layer test and anti-interference test and improves the response speed and stability of potential. The linear response range of this disposable screen-printed electrode to Ca2+ is 10−6∼10−1 M, the detection limit is 10−6.2 M, and the response time is about 15 s. The electrode can accurately and quickly determine the level of Ca2+ in serum samples of dairy cows.

Synthesis, characterization and enhancing efficiency of composite CuO2/CuO nanostructures deposited on porous activated carbon for supercapacitors electrode applications

The efficiency of supercapacitor (SC) electrodes made from hydrothermally obtained composite Cu2O/CuO nanostructures/activated Cassia fistula dry seed pod carbon (CCu NSs) was improved. X-ray results indicated a mixed phase of monoclinic CuO and cubic Cu2O nanoparticles. Morphology and dispersion of both phases were revealed using field emission scanning electron microscopy and transmission electron microscopy. Raman spectra indicated the characteristic peaks of disordered and graphitic carbon in all samples. Fourier transform infrared spectra confirmed the vibrational modes of Cu and O atoms. Specific surface area and pore-size distribution of samples were determined using a nitrogen adsorption-desorption isotherm. X-ray photoelectron spectroscopy was employed to examine their chemical surfaces. Electrochemical properties were evaluated with cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy with three-electrode and symmetric SC cell experiments in KOH. After a 5000 cycle GCD test at 5 A g−1, CCu-2 NS electrode demonstrated an exceptional EDLC performance with 91.2 % capacity retention and specific capacitance 277.80 F g−1 at 0.5 A g−1. Additionally, the fabricated CCu-2//CCu-2 NSs SC cell showed an outstanding 62.3 % capacity retention at 1 A g−1 after a 5000 cycle GCD test with high energy (Esd) and power densities (Psd) of 11.39 Wh kg−1 and 629.34 W kg−1, respectively.

Electrode Applications Using Organic Thin Films with Three-Dimensional Structures

Electrode Applications Using Organic Thin Films with Three-Dimensional Structures

Emulsion-assisted polyaniline grown on molybdenum diselenide nanoflowers for efficient counter electrode application in dye-sensitized solar cells

ABSTRACT Molybdenum diselenide (MoSe2) is often composed with conducting polymers like polyaniline (PANI) to lower the stacking and increase the active sites for catalysis. The method of polymerization and the concentration of monomer play a significant role in the growth of PANI nanostructures over the MoSe2 surface. Here, MoSe2-PANI nanocomposites have been synthesized with different molar concentrations of the monomer in the emulsion of chloroform and distilled water using ammonium persulfate (APS) as the initiator. The increased surface area of the composite MPAN (1:1) compared to pristine MoSe2, as observed from the FESEM and BET study, is fruitful for counter-electrode application in dye-sensitized solar cells (DSSC). The lower Rct values for the MPAN (1:1) and increased current in cyclic voltammetry further approved the suitability of the MoSe2-PANI as a counter electrocatalyst. The counter electrodes against N719 dye-sensitized TiO2 photoanode in DSSC yielded the best results for MPAN (1:1), generating an efficiency of 6.45%.

MXenes-based Multifunctional Nanomaterials for Lithium-ion Batteries: Opportunities and Challenges

Abstract: MXene-based multicomponent materials are 2D substances derived from transition metal (M) with carbide/nitride combinations having several propitious uses, including application in energy storage devices for high-performance electrodes for Lithium-ion batteries (LIBs) fabrication. The suitability of these new classes of materials for LIB electrodes can be attributed to their high conductivity combined with their excellent surface properties desirable for electrode applications, such as fast charge-discharge capability, high storage capacity and high rate capacity. However, there are several challenges possessed by MXene-based nanomaterials in the application of their electrodes in future flexible and wearable devices, demanding more research work and development strategies. After a brief overview of MXenes used in batteries, this paper deals with the synthesis, morphology-properties correlations, and their performance. Finally, this paper headlines the advantages, limitations, and challenges of MXene-based electrodes for LIBs, ending with concluding remarks.

The Application of Picein Wax Carbon Composite Electrode for Plant-Based Milk Profiling

This work demonstrates the successful application of the picein wax carbon composite electrode (PWCCE) for profiling both commercial and homemade plant milks. Picein wax was utilized as an unconventional binder. The resulting electrode paste exhibited a solidified and hard texture, enabling its use in a manner analogous to that of the glassy carbon electrode. Differential pulse voltammetry (DPV) with an automated measurement and recording procedure was employed to obtain plant-based milk profiles. The utilization of operator-independent measurement procedures yielded high-quality electrochemical fingerprints suitable for subsequent calculations. To interpret the data, unsupervised machine learning methods were implemented, such as principal component analysis (PCA) and cluster analysis. These chemometric techniques confirmed the electrode effectiveness of the construction for this type of research. Moreover, they proved valuable in distinguishing between plant-based milk and cow’s milk, including two different variants: whole milk and lactose-free milk.

Safety of the Radiofrequency Balloon for Pulmonary Vein Isolation: A Focus on Lesion Metric Analysis of Posterior Electrodes.

Previous clinical studies on pulmonary vein isolation (PVI) with radiofrequency balloons (RFB) reported safe and effective procedures for a 20 s RF delivery via posterior electrodes. Recent recommendations from the manufacturer suggest reducing the application time to 15 s on the posterior wall (PW) when facing the esophagus region. Here, we retrospectively assess whether 15 s of RF delivery time on posterior electrodes is safe while still ensuring lesion metrics of sufficient quality. This retrospective study included 133 patients with paroxysmal and persistent atrial fibrillation who underwent PVI using an RFB (Heliostar, Biosense Webster, Inc., Irvine, CA, USA) at two European centers. The ablation protocol was set for an RF duration of 20 s/60 s for the posterior/anterior electrodes. A multielectrode temperature probe was systematically used. In the case of an esophageal temperature rise (ETR) above 42 °C (ETR+), an endoscopic evaluation was performed. All posterior electrode lesion metric dynamics (temperature (T) and impedance (Z)) were collected from the RFB generator and analyzed offline. In total, 2435 posterior electrode applications were analyzed. With an RF delivery of 19.8 (19.7-19.8) s, the median impedance drop was 18.4 (12.2-25.2) Ω, while the temperature rise was 11.1 (7.1-14.9) °C. Accordingly, impedance (84.6 (79.3-90.2) Ω) and temperature plateaus (38 (35.3-41.1) °C) were reached at 13.9 (10.6-16) s and 16.4 (12.6-18.5) s, respectively. Overall, 99.6% and 95.8% of electrodes reached 90% (16.6 Ω) and 95% (17.5 Ω) of their impedance drops within 15 s of RF delivery, while 97.2% and 92.8% achieved 90% (34.2 °C) and 95% (36.1 °C) of their temperature rise to reach the plateaus within 15 s of RF delivery. An ETR >42 °C occurred in 37 (30.1%) patients after 17.7 ± 2.3 s of RF delivery. In the ETR+ group, the impedance drop and temperature rise on the posterior electrodes were higher compared to patients where ETR was <42 °C. Two asymptomatic thermal esophageal injuries were observed. In conclusion, 15 s of RF delivery on the posterior electrodes provides a good balance between safety, with no esophageal temperature rise, and efficacy with high-profile lesion metrics.

Transferable Highly (001) Oriented Sb2Se3 Nanorod Films on Flexible Substrates for Innovative Optoelectronic Devices

AbstractThin films of antimony chalcogenides, Sb2X3 (X = S, Se, or SxSe1−x), comprised of (001) oriented nanorods are highly desirable for optoelectronic applications owing to their light trapping capacity and highly efficient charge transport along the optimally aligned quasi‐1D (Sb4X6)n ribbons. Here, highly (001) oriented Sb2Se3 nanorod (Sb2Se3NR) layers are obtained via a novel template growth method, and transfer these layers to functional substrates via a polymer‐assisted technique. Transferable layers overcome the current challenges associated with achieving oriented growth directly on the desired substrate. Using a combination of a low‐temperature processable SnO2 nanoparticle transport layer and encapsulation/etching techniques photodetector devices are fabricated with excellent electrical contact. The optimized transferred devices show broad range photoresponse with signal‐to‐noise ratios up to 105 and responsivities reaching 0.96 mA W−1. Importantly, access to low‐temperature processing enables the fabrication of flexible devices. Based on this platform, a proof‐of‐concept self‐powered flexible heart rate monitor is fabricated. The achievement of transferable Sb2Se3NR layers introduced in this work is expected to be readily applicable to generate new (001) Sb2Se3 device architectures that may otherwise not be achievable via direct deposition, with application in photoelectrochemical water splitting, battery electrodes, and solar cells.

Improving the Uniform Distribution of Nano-Ag in Al-Doped ZnO Film to Enhance Its Application in Soft Touch Sensing Electrodes

Improving the Uniform Distribution of Nano-Ag in Al-Doped ZnO Film to Enhance Its Application in Soft Touch Sensing Electrodes

Scalable synthesis of binder-free hierarchical MnCo2O4 nanospikes/Ni(OH)2 nanosheets composite electrodes for high-capacity supercapatteries

Supercapatteries have received great attention in recent years due to its excellent charging storage capabilities. The effective electrochemically active surface area of the electrode is crucial in obtaining high capacity in supercapatteries. Herein, we present a scalable synthesis of binder-free hierarchical MnCo2O4 (MCO) nanospikes/Ni(OH)2 (NiOH) nanosheets (MCO/NiOH) nanocomposites for supercapattery electrode application. The MCO/NiOH nanocomposites are synthesized by the two-step hydrothermal method at low-cost without affecting nanostructures and further used as electrodes in fabricating a supercapattery. The synergistic effect of the NiOH nanosheets and MCO nanospikes helps to enhance the electrochemical charge storage performance when compared to their counterparts. The growth of NiOH nanosheets over the MCO nanospikes helps to suppress the self-discharge nature of MCO nanospikes otherwise. The MCO/NiOH//activated carbon supercapattery fabricated in the asymmetric configuration delivers a maximum specific capacity of 890C/g with a high energy density of 75.2 Wh/kg. The MCO/NiOH//activated carbon supercapattery exhibits a capacity retention of 86 % after completing 5000 charge/discharge cycles. Therefore, MCO/NiOH nanocomposite electrodes are capable candidates for the next-generation electrochemical energy storage systems.

Effect of boron doping levels on the microstructure and characteristics of high-quality boron-doped diamond electrodes prepared by MPCVD

In order to fully understand the relationship between boron doping level and material characteristics, a series of high-quality boron-doped diamond (BDD) electrodes with different boron doping levels (B/C ratios = 1000–5000 ppm) were prepared on a silicon substrate using a self-designed microwave plasma chemical vapor deposition (MPCVD) reactor in this study. The relationship between surface morphology, structural composition, chemical bonding state, electrical conductivity and electrochemical properties of BDD electrodes was investigated systematically. With the increase of boron doping level, the grain size of the BDD electrode tends to decrease, the crystal orientation tends to be dominated by (111) orientation, the conductivity increases sharply and then gradually stabilizes, while the width of the potential window tends to decrease (4.39 V to 3.95 V from 1000 ppm to 5000 ppm), and the reversibility and stability of the electrode improves significantly. In addition, such high-quality BDD electrodes also exhibit a higher sensitivity (0.1176 μAμM−1 cm−2) and lower limit of detection (0.276 μM) in the detection of dopamine. The boron doping level in BDD electrodes plays a prominent role in material characteristics such as surface morphology, structural composition, chemical bonding state, electrical conductivity and electrochemical properties. Despite the challenging synthesis of pure sp3 carbon materials at high boron doping levels, the BDD electrodes prepared in this study exhibit high quality without sp2 defects even with high boron doping levels, and possess extremely low resistivity (~10−3 Ω·cm) and a wide electrochemical potential window (~4 V), which has not been achieved in other previous research works and offer great potential in the electrochemical applications of BDD electrodes.

Cobalt/Nitrogen Co-Doped Carbon Materials Enhance the Reaction Rate of Sodium-Potassium Alloy Electrodes.

Sodium-potassium (NaK) alloy electrodes are ideal for next-generation dendrite-free alkali metal electrodes due to their dendrite-free nature. However, issues such as slow diffusion kinetics due to the large K+ radius and the loss of active potassium during the reaction severely limit its application. Here a novel cobalt/nitrogen-doped carbon material is designed and it is applied to the construction of a NaK alloy electrode. The experimental and theoretical results indicate that the confining effect of the nitrogen-doped graphitic carbon layer can protect the cobalt nanoparticles from corrosion leaching, while the presence of Co─Nx bonds and cobalt nanoparticles provides more active sites for the reaction, realizing the synergistic effect of adsorption-catalytic modulation, lowering the K+ diffusion energy barrier and promoting charge transfer and ion diffusion. The application of this electrode to a symmetrical battery can achieve more than 1800 stable cycles under a current density of 0.4mA cm-2 and a charge/discharge specific capacity of 122.64 mAh g-1 under a current of 0.5C in a full battery. This finding provides a new idea to realize a fast, stable, and efficient application of NaK alloy electrodes.

Electrochemical Applications of Porous Materials Derived from Coal

As the world shifts from the use of coal to alternatives for electricity generation, including renewable energy, interest arises in developing alternative uses for coal. There are vast U.S. coal reserves, much of which are in historically underrepresented or economically depressed regions. This has created environmental concerns in these regions, especially related to legacy impoundments and other waste coal issues. Finding alternative uses for that coal could create new job opportunities in these regions while also addressing climate change. Currently, there are very few applications for coal outside of its traditional use for electricity production.This group has been developing alternative uses for coal, including uses in energy storage applications. This presentation will discuss the development of macroporous coal materials that then can be further processed into micron or nanometer size particles for porous materials. The characterization of these porous materials will be presented. Graphitized materials for use in lithium ion battery electrodes will be presented. Nanoscale materials such as graphene and carbon quantum dots derived from coal will be presented, along with their application in porous electrodes for batteries and capacitors.

A More Controllable Laser Reduction of Graphene Oxide Membrane for Electrode Applications

Reduced graphene oxide (rGO) has attracted significant attention as an active electrode material for sensors and flexible energy devices due to its high electric conductivity and large surface area. rGO is usually obtained from graphene oxide(GO) through a thermal, chemical, photochemical, and electrochemical reduction process. Compared to the other reduction strategy, laser reduction is a single-step, precise, low cost, and chemical-free processing that can be directly applied on the GO membrane at room temperature in an ambient condition.The laser irradiation parameter, such as laser source, power, speed, and frequency, plays an important role in reduction optimization. In general, the quality of the rGO is not as high as that of pristine graphene because of incomplete reduction, and oxygenated defects involved in the reduction process.The not fully removed oxygenated function group not only influence the sensitivity and selectivity of the electrode, but also influences response time and recovery time during sensing and the electrochemical window of the supercapacitor made with those rGO electrode.This study aims to develop reduced graphene oxide (rGO) through laser irradiation for application in supercapacitors and electrochemical sensors as electrodes. GO membranes were fabricated with a layer-by-layer assembly process first then further reduced through conventional CO2 laser reduction. The laser irradiation parameters including intensity, frequency, and scan speed will be optimized to achieve the reduction up to maximi, C/O ratio. The effects of the reduction will be characterized and evaluated using scanning electron microscope (SEM), Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD)spectroscopy, and four-point probe station. The influence of the humidity on the impedance of the rGO electrode and the capacitance of the planar supercapacitor made with rGO electrode will also be analyzed for potential application of as-prepared rGO electrodes in supercapacitors and humidity sensors.

Metallic Organic Framework (MOF) Applications in Novel Lithium-Sulfur Batteries

Today lithium-ion batteries are the basis of portable energy source. Wildly used in electronic devices and electric vehicles lithium-ion type of batteries became a standard. Despite good electrochemical performance and their universality, fast development of the market for efficient power sources makes them unable to meet this challenge. As a promising competitor or even a successor of lithium-ion batteries often named are lithium-sulfur batteries. It’s mostly because of their high specific capacity (1675 mAh g-1) and relatively big deposit of sulfur on Earth. The main reason, why this type of batteries is not commercialized yet is the problem with the application and stability of the sulfur electrode. The expansion of the sulfur when charging, its insulation and dissolution in organic solvents from the electrolyte, resulting the creation of polysulfides chains, are the remaining problems to solve before lithium-sulfur batteries could be spread in the commerce devices. To solve these issues many additives and compounds have been examined. One of the idea is to use metal-organic frameworks (MOFs) as a sulfur host on the electrode. Because of the porosity of the structure of these materials they are able to “hold” sulfur inside them. Not only it improves the electronic conductivity but also can be a solution to reduce the electrode expansion and sulfur reactions with electrolyte. This report presents a few methods of the possible ways of doping MOFs with sulfur and electrode slurry preparation. All the research was made in cooperation of Warsaw University of Technology from Poland and NTNU and SINTEF from Norway in M-ERA.NET 2 MOGLiS project.

Enabling the Production of Homogeneous High-Load Positive Electrodes by Tailoring the Electrode Formulation – a Conductive Additive and Solvent Approach

The automotive industry experiences a substantial change due to electrification of major parts of the transportation system by using lithium ion batteries (LIBs). To facilitate this transition, low cost and high energy density LIBs produced under the most sustainable conditions possible are required. These objectives are amongst others strongly related with the positive electrode. Thus, in order to achieve enhanced energy densities on cell level, the application of high-load positive electrodes for various cell systems ranging from lithium ion to lithium metal batteries is inevitable. However, to ensure high lithium ion mobility within thick composite electrodes and to obtain maximized capacity utilization, it is crucial to tailor the electrode microstructure. With regard to the production, detrimental effects like binder-migration can occur upon drying of thick electrodes inducing inhomogeneous distribution of binder and conductive additive within the electrode coating. Beyond that, the effect of lateral coating shrinkage resulting in electrode cracking during drying plays an increasingly significant role with increasing electrode thickness.The application of high solid contents (SC) during electrode paste processing can widely suppress the effects of binder migration and crack formation.[1,2] However, elevated SCs result in increasing paste viscosities leading to practical limitations for homogeneous electrode coating. By using nano-scale and micro-scale spherical, linear and three-dimensional conductive additives like carbon microfibers (CMF) or conductive graphite (CG) in addition to carbon black (CB), the adjustment of an appropriate paste viscosity can be facilitated. The addition of more carbonaceous additives acting as conductive additive as well as processing additive resolves the rheological requirements for an electrode paste with 80% SC and significantly influences the pore structure of the electrode. Thus, tailoring active and inactive components is crucial to enable processing of high SC electrode pastes with an appropriate viscosity in conjunction with the production of thick electrodes exhibiting an optimized pore structure benefiting the electrochemical performance. The additional introduction of carbon nanotubes (CNTs) leads to the formation of segregated networks providing more stability within the electrode and a favorable electrode microstructure. Moreover, the use of CNTs benefits the electrochemical performance by immensely boosting electronic conductivity resulting in higher rate capability and increased capacity retention. The various electrode formulations containing up to three different conductive additives were compared to the benchmark formulation without further additives in terms of electronic conductivity, adhesion, pore structure and electrochemical performance. Different electrode formulations were investigated and compared regarding the composite electrode adhesion strength, electronic conductivity, microstructure and electrochemical performance over 400 cycles in a coin cell setup with a graphitic negative electrode. However, the optimized formulation containing CNTs enables the production of thick positive electrodes exhibiting significantly higher areal capacities up to 8 mAh cm-2 with superior electrochemical properties and higher content of active material in the formulation resulting in higher energy densities on cell level. In a next step, the state-of-art processing solvent N-Methyl-2-pyrrolidon (NMP) was targeted with the goal of replacing NMP with a non-toxic solvent. The influence of a co-solvent on the electrode paste viscosity was investigated to further increase the SC, lower production costs and enable improved environmental benignity.A comprehensive study on tailoring the rheological, structural and electrochemical properties by processing additives is presented. The increase of the SC to 80% is a first step towards the reduction of the ecologic and economic footprint for LIB production while simultaneously enabling electrodes with high areal capacities exhibiting increased rate capability and capacity retention enabled by the addition of CNTs.[1] J. Seeba, S. Reuber, C. Heubner, A. Müller-Köhn, M. Wolter, A. Michaelis, Chemical Engineering Journal Volume 402, 2020, 125551. [2] L. Ibing, T. Gallasch, P. Schneider, P. Niehoff, A. Hintennach, M. Winter, F. M. Schappacher, Journal of Power Sources 423, 2019, 183–191.

Catalyst Application in Three-Dimensional Porous Electrodes for Alkaline Electrolysis

Hydrogen is critical in the green transition, and a key system for producing green hydrogen is through alkaline electrolysis. Although the alkaline electrolyzers are mature and commercially available, vast improvements are still expected in the future 1.Traditional and most commercially applied alkaline electrolyzer electrodes are made from massive nickel plates (or nickel-plated steel plates) with some scattered perforation. With the ongoing development of thin alkaline ion‐conducting membranes with low internal resistance, the benefit of three‐dimensional porous electrodes becomes obvious. With such electrodes, there will be no blind spots and the active catalytic area can be increased significantly. Today, most groups developing such 3D electrodes use commercial nickel foam as substrate. This limits the options to what is available in the market, moreover the purchase cost is high.The present work aims at developing high‐performing three‐dimensional hydrogen and oxygen evolution electrodes for alkaline electrolysis. The focus will be on the application of nanostructured electrocatalysts into three‐dimensional electrode structures, similar to nickel foams.The results obtained, so far, show homogeneous formation of nanoparticles on the surface. The analysed samples show mechanical flexibility as soon as the particles are deposited but samples become rigid after testing in a half cell setup with KOH 1 M electrolyte. Further analysis will explore changes to the microstructure. The roughness factor calculated by non-faradaic cyclic voltammetry is in the range of 75 cm2 ECSA / cm2geometric, showing higher value than the commercial Nickel foam.Initial experiments are carried out on as-prepared samples, but more advanced catalysts are also explored based on state-of-the-art materials. [1] IRENA - Green Hydrogen Cost Reduction: Scaling up Electrolysers to Meet the 1.5 °C Climate Goal, International Renewable Energy Agency, Abu Dhabi (2020)

Optimization of ternary composite @PANI/MoO3/h-BN and its electrochemical evaluation as an electrode material for supercapacitor application

The rapid charge-discharge process, high power density and longer cycle life which supercapacitor possess paves way as an important energy storage device in the electronic technology sector. Fast expanding applications in electric vehicles and portable electronics demand high energy storage electrodes. The expansive applications of two dimensional hexagonal boron nitride (h-BN) nanostructures accelerate usage in energy storage systems. Synthesis of Ternary composite consisting of polyaniline (PANI), h-BN (hexagonal boron nitride), molybdenum trioxide (MoO3) is reported with highest capacitance 518 F/g for PMB-135 composite at current density of 1 A/g. The highest energy density among all the composites was PMB-135 observed as 10.34 Wh/kg. This study with controlled size and uniformity may provide extensive self-attaining property for high performance energy storage materials.

Irradiation methods for engineering of graphene related two-dimensional materials

The research community has witnessed an exceptional increase in exploring graphene related two-dimensional materials (GR2Ms) in many innovative applications and emerging technologies. However, simple, low-cost, sustainable, and eco-friendly methods to manufacture large quantities and high-quality GR2Ms still remain an unsolved challenge. To address limitations of conventional wet chemical-based exfoliation methods using graphite resources, the top-down irradiation approach has proven to be an ultrafast, effective, and environmentally friendly technology for scalable exfoliation, production, and processing of GR2Ms providing new properties for emerging applications. Significant advancements have been made for preparation of broad range of GR2Ms from graphite, such as graphene, graphene oxide, and reduced graphene oxide, and their doped, functionalized and modified forms over the past two decades, thanks to the availability of photon and ion irradiation techniques, such as microwave, infrared, ultraviolet, solar, x-ray, gamma, laser, and plasma. This review presents recent advances on the application of these various irradiation techniques and highlights their mechanism, differences in properties of prepared GR2Ms, and their advantages and disadvantages in comparison with other conventional methods. The review provides an insight into the irradiation strategies and their prospective applications to produce, at a large scale, low-cost, high-quality GR2Ms for practical applications in transparent electrodes, optoelectronic devices, sensors, supercapacitors, protective coatings, conductive inks, and composites.

Synthesis of UV-curable disulfide functionalized polysiloxane for stretchable gold electrodes with microcrack

Stretchable electrodes prepared by conductive layer and elastomer were widely applied in sensors, flexible electronic devices and health detections. The microcracks in conductive layer strained synergistically with the elastomer, achieving linearly changing of conductivity with stretch. However, the interactions between the metal conductive layers and the substrates need to be enhanced for synergistical strain. In addition, the preparation of stretchable electrode with both high gauge factor (GF) and high stretchable conductivity is still a challenge. The study reported the synthesis of lipoic acid functionalized polysiloxane elastomer (LFPSE), which adhered gold nanoparticles to prepare stretchable electrodes. Elastomer were cured through thiol-ene click polymerization and stretchable electrode was prepared through evaporating gold nanoparticles on LFPSE in vacuum. S-Au bond was characterized by Raman spectroscopy and XRD. Tensile conductivity was performed through microcrack propagation of Au. The conductivity of the LFPSE stretchable electrode increased linearly with a maximum strain of 112.7%, and the GF was 127.89. Finally, LFPSE stretchable electrode was applied to detect muscle movement. The study of UV curable polysiloxane elastomer based on thiol-ene with S-Au interaction provided a potential application in wearable flexible electronic devices and stretchable electrodes.