Mylar Research Articles

Influence of flexible substrate nature covered with ITO on the characteristics of organic heterostructures fabricated by laser deposition techniques

Laser thin layer deposition technologies were applied to develop organic heterostructures on flexible transparent conductive electrode (TCE). Flexible substrates such as flexible glass (FG), polyethersulfone (PES), amorphous polyethylene terephthalate (PET-A) and biaxially-oriented polyethylene terephthalate (PET-B) were employed to assess the influence of the substrate type on the optical and electrical characteristics of the organic devices. For comparison reason, the organic heterostructures were fabricated on rigid glass substrate and commercially available indium tin oxide (ITO)-coated PET. Hence, flexible and rigid glass substrates were coated with ITO film by pulsed laser deposition (PLD) at low fluence, subsequently a blend layer based on zinc phthalocyanine (ZnPc) and N, N′-bis-(1-dodecyl)perylene-3,4,9,10 tetracarboxylic diimide (AMC14) being deposited by matrix assisted pulsed laser evaporation (MAPLE) on the TCE film. The investigations evidenced that the roughness and the substrate type can strongly influence the properties of the ITO layer deposited by PLD as well as the optical and electrical characteristics of the organic heterostructures based on the blend layer deposited by MAPLE. Thus, the lowest roughness (0.8 nm) and the best Hall mobility (41.9 cm2/Vˑs) were achieved for ITO coatings deposited on flexible glass substrate. Also, the highest current density value (9.3 × 10− 4 A/cm2 at 0.5 V) was reached for the organic heterostructures fabricated on this type of flexible substrate.

Recycled PET Packaging Materials of Improved Toughness— Importance of Devitrification of the Rigid Amorphous Fraction

AbstractDegradation, a common problem faced during the processing of recycled poly(ethylene terephthalate) (PET), leads to significant embrittlement of the products, as a result of which the material loses its applicability. Increased crystallization rate of the short chains of recycled PET and obstructed mobility of the amorphous phase are the main causes of enhanced brittleness. In this research, a straightforward method is proposed for improving the toughness of recycled PET products, namely the devitrification of the rigid amorphous phase by thermal annealing, which results in enhanced molecular mobility in the amorphous fraction, thereby promoting ductile deformation. The effects of thermal annealing conditions are comprehensively evaluated on the microstructure and macroscopic properties, i.e., impact resistance, of recycled PET films. The perforation energy value of the recycled PET film is found to increase to its threefold, reaching a value higher than 18 J mm−1, as a result of 10 s thermal treatment at 120 °C. Differential scanning calorimetry, dynamic mechanical analyses, and thermally stimulated depolarization current measurements provide evidence for the devitrification of the rigid amorphous fraction under these conditions, which is the key to efficient enhancement in toughness.

Flexible Electrolyte Sheets Using Sulfonated Cellulose Nanofiberfor Sheet-Type All-Solid-State Batteries

With the rapid spread of electric vehicles that do not use fossil fuels for suppression of global warming, all-solid-state batteries (ASSBs) have been studied as a next-generation battery to improve the cruising range and safety. In general, ASSBs use solid-state electrolyte such as polymer or inorganic electrolytes instead of organic electrolyte solutions, which prevent from electrolyte leakage and its degradation especially at high temperatures. Therefore, it is possible to simplify for the cell design and to increase the energy density. However, for the practical use relatively high interface resistance between electrode and solid-state electrolyte is one of the critical problems. Recently, addition of cellulose nanofiber (CNF) into polyethylene oxide (PEO) electrolyte was reported to improve flexibility and mechanical strength. Also, this method can reduce the interface resistance and improve the cycle performance [1]. In this study, we prepared new composite electrolyte membranes by using sulfonated CNF (S-CNF, Yokokawa Bio Frontia Inc.), together with a low molecular weight PEO, i.e. tetraglyme (G4), and some amounts of ceramic powders to support the ionic conductivity and mechanical strength. The electrochemical properties were investigated by using SUS | SUS and Li | Li symmetric cells to elucidate the mechanism of ionic transport. Mixtures of S-CNF, Lithium-Ion Conducting Glass-Ceramics (LiCGCTM, OHARA) or SiO2 powders, Lithium Bis(trifluoromethanesulfonyl) imide (LiTFSI) salt and G4 solvent were prepared in a predetermined ratio. The resulting solutions were coated onto PET film and dried in vacuum to form membranes, and then peeled off to obtain the S-CNF composite electrolyte membranes. The ion conductivity was measured by AC impedance method at a frequency range from 1 MHz to 100 mHz and applied voltage of ±50 mV by using a SUS | SUS symmetric cell. The interface resistances were evaluated by using a Li | Li symmetric cell to subject to a Li dissolution/ deposition test at 25°C. The tests was conducted in a constant current mode with a voltage range of -2.0 to 2.0 V, a current density of 0.50 mA cm- 2 and a capacity limit of 0.50 mAh cm-2. Fig. 1 shows Nyquist plots of a LICGC pellet and the S-CNF composite membranes containing LiCGC or SiO2 powder. The composite membranes has no semicircular component different from the LICGC pellt. This indicates that the interface resistance between the electrolyte menbranes and Li metal is drastically reduced owing to the flexibility. Also, both case of S-CNF composite menbrane exhibited almost same plots. This indicates that the contribution for ionic conductivity by the LICGC solid-state electrolyte is smaller than that by the polymer electrolyte conponent of LiTFSI/G4. In fact, the ion conductivity calclated from the Nyquist plots were 55.0 and 51.7 μS cm-1 for the S-CNF composite menbranes containing LICGC and SiO2 powder, respectively. These values were five times higher than that of pure LICGC pellet (9.53 μS cm-1). On the other hand, Li |Li symmetric cell test exhibited a quite stable polarization curves for the both S-CNF menbranes remaining the overpotential below 5 mV for up to 200 cycles. This also indicates the good chemical stability against Li metal. The mechanism of ionic conductivity, the role of S-CNF in the composite menbranes and the mechanical strength will be totally discussed in the meeting.

High-Performance Fiber Optic High-Frequency Cantilever Acoustical Transducer Based on PET Film

High-Performance Fiber Optic High-Frequency Cantilever Acoustical Transducer Based on PET Film

Preparation mechanism and characterization of PET/Cu composite foils

PET/Cu composite foils are expected to have widespread applications due to their lightweight, good bendability and excellent electrical conductivity. However, efficiently and stably preparing copper cladding layers on the surface of PET film with good bonding to the substrate remains a challenge. In this study, by optimizing the process route and adopting a synergistic method involving electroless plating and electroplating, PET/Cu composite foils with excellent conductivity and robust bonding can be successfully prepared. The experimental results indicate that the optimal performance of PET/Cu composite foils is achieved when the PET substrate is roughened with KMnO4/H+ solution, activated with salt-based colloidal palladium, subsequently treated with a weak alkaline electroless nickel plating solution for 5 min, and plated copper at a current density of 0.4 A·dm−2. The adhesion strength of the PET/Cu composite foils meets the ASTM 5B standard and the electrical conductivity reaches up to 4.17 × 107 S/m. The method proposed in this study offers an efficient and concise approach for preparing high-quality PET/Cu composite foils that hold great potential for diverse applications in flexible copper clad laminates.

Nonlinear resonance of fractional order viscoelastic PET films under temperature loading

The effects of oven temperature during printing on nonlinear vibration for fractional-order PET films are considered in this paper. The effect of temperature, fractional order modelling and some other parameters are analysed with respect to the response of the resonance. Fractional order kelvin-Voigt ontological relationship is used to describe the characteristics of viscoelastic materials. The differential equations for nonlinear vibrations are inferred according to the second law of Newton and the theory of von Karman. Discretization for nonlinear equations on locomotion using the Bubnov–Galerkin method. Forced co-oscillatory amplitude-frequency response equations for thin-films systems under temperature loading were calculated using the multiple scales method. Results of numeral results show that temperature, and fractional-order visco-elastic modelling influence the membrane's response to resonance. These results provide a basis for studying fractional-order visco-elastic films vibrations and identifying regions of stable operation in moving systems to prevent divergent instabilities for flexible electronic device manufacturing.

Enabling High Strength and Toughness Polyurethane through Disordered-Hydrogen Bonds for Printable, Recyclable, Ultra-Fast Responsive Capacitive Sensors.

The rapid advancement of smart, flexible electronic devices has paralleled a surge in electronic waste (e-waste), exacerbating massive resource depletion and serious environmental pollution. Recyclable materials are extensively investigated to address these challenges. Herein, this study designs a unique polyurethane (SPPUs) with ultra-high strength up to 60MPa and toughness of 360MJ m-3. This synthetic SPPUs can be fully recycled at room temperature by using green solvents of ethanol. Accordingly, the resultant SPPU-Ni composites, created by mixing the ethanol-dissolved SPPUs solution with nickel (Ni) powder, effectively combine the flexibility and recyclability of SPPUs with the electrical conductivity of the nickel filler. Notably, this work develops the printable capacitive sensors (PCBS) through transcribing the paste of SPPUs-Ni slurry onto PET film and paper using screen-printing technology. The devised PCBS have fast response time ≈50ms, high resolution, and multiple signal recognition capabilities. Remarkably, SPPUs and Ni powder can be fully recycled by only dissolving the waste PCBS in ethanol. This work offers a sustainable solution to the growing e-waste problem in recyclable flexible electronics.

Manufacturing of the highly active thermophile PETases PHL7 and PHL7mut3 using Escherichia coli

BackgroundThe global plastic waste crisis requires combined recycling strategies. One approach, enzymatic degradation of PET waste into monomers, followed by re-polymerization, offers a circular economy solution. However, challenges remain in producing sufficient amounts of highly active PET-degrading enzymes without costly downstream processes.ResultsUsing the growth-decoupled enGenes eX-press V2 E. coli strain, pH, induction strength and feed rate were varied in a factorial-based optimization approach, to find the best-suited production conditions for the PHL7 enzyme. This led to a 40% increase in activity of the fermentation supernatant. Optimization of the expression construct resulted in a further 4-fold activity gain. Finally, the identified improvements were applied to the production of the more active and temperature stable enzyme variant, PHL7mut3. The unpurified fermentation supernatant of the PHL7mut3 fermentation was able to completely degrade our PET film sample after 16 h of incubation at 70 °C at an enzyme loading of only 0.32 mg enzyme per g of PET.ConclusionsIn this research, we present an optimized process for the extracellular production of thermophile and highly active PETases PHL7 and PHL7mut3, eliminating the need for costly purification steps. These advancements support large-scale enzymatic recycling, contributing to solving the global plastic waste crisis.

Impact of dicarboxystilbene impurities on the properties of swift heavy ion latent tracks in PET films

We present a new hypothesis and supporting experimental evidence about the essential role played by small impurities of dicarboxystilbene in the process of UV treatment of PET films irradiated with swift heavy ions (SHI). This treatment both forms highly selective membranes with permeability values comparable to natural ones (the track-UV technique) and sharply accelerates the etching of latent tracks in membrane production (the track-etching technique). We hypothesize (1) that these high permeability value is due to the presence of a molecular motor of an Archimedes screw type in the central part of the latent track formed by photoinduced trans-cis isomerization of dicarboxystilbene molecules that are anchored in helical conformations in the latent track; and (2) that the acceleration of etching rates is due to the preferential accumulation of phenanthrene-type molecules in the central part of the latent track due to the existence of a cyclization channel for photoexcited molecules of cis-dicarboxystilbene. In the presence of alkali solution, phenanthrene molecules release electrons which behave as strong anions in aqueous solution, catalyzing alkaline hydrolysis of PET molecules in the central part of the track. We present experimental observations of photoinduced changes in transmission light intensity after track-UV light treatment of both pristine and SHI irradiated PET films that confirm the presence of trans-cis isomerization of dicarboxystilbene molecules and show their contribution to the formation of new helical conformations in SHI irradiated PET films during the light treatment.

Mechanisms of Polyethylene Terephthalate Pellet Fragmentation into Nanoplastics and Assimilable Carbons by Wastewater Comamonas.

Comamonadaceae bacteria are enriched on poly(ethylene terephthalate) (PET) microplastics in wastewaters and urban rivers, but the PET-degrading mechanisms remain unclear. Here, we investigated these mechanisms with Comamonas testosteroniKF-1, a wastewater isolate, by combining microscopy, spectroscopy, proteomics, protein modeling, and genetic engineering. Compared to minor dents on PET films, scanning electron microscopy revealed significant fragmentation of PET pellets, resulting in a 3.5-fold increase in the abundance of small nanoparticles (<100 nm) during 30-day cultivation. Infrared spectroscopy captured primarily hydrolytic cleavage in the fragmented pellet particles. Solution analysis further demonstrated double hydrolysis of a PET oligomer, bis(2-hydroxyethyl) terephthalate, to the bioavailable monomer terephthalate. Supplementation with acetate, a common wastewater co-substrate, promoted cell growth and PET fragmentation. Of the multiple hydrolases encoded in the genome, intracellular proteomics detected only one, which was found in both acetate-only and PET-only conditions. Homology modeling of this hydrolase structure illustrated substrate binding analogous to reported PET hydrolases, despite dissimilar sequences. Mutants lacking this hydrolase gene were incapable of PET oligomer hydrolysis and had a 21% decrease in PET fragmentation; re-insertion of the gene restored both functions. Thus, we have identified constitutive production of a key PET-degrading hydrolase in wastewater Comamonas, which could be exploited for plastic bioconversion.

A High-Gain, High-Efficiency Transparent and Flexible Antenna for Vehicular Communication

A high-gain high-efficiency flexible and transparent film antenna in millimeter-wave is proposed in this paper. Comb structure which can be regarded as developed from the grid array structure is employed to mitigate the loss of the feeding network caused by the lossy metal mesh. The gain of the antenna has low sensitivity to the sheet resistance, which is promising in developing large-scale and high-performance transparent antenna. A large-scale ([Formula: see text]@28[Formula: see text]GHz) antenna is designed and fabricated using transparent metal mesh film with sheet resistance of 0.1[Formula: see text][Formula: see text]/sq and a thin PET film substrate. Bending measurement shows the antenna has excellent mechanical flexibility. A peak gain of 15.92[Formula: see text]dBi, radiation efficiency of 65.1%, optical transparency of 84% and 1,000-times bending are obtained. To the best of our knowledge, it is the highest gain and radiation efficiency flexible-transparent antenna reported thus far, which provides a glass-integrated antenna solution for vehicular communication.

A High-Throughput Screening Platform for Engineering Poly(ethylene Terephthalate) Hydrolases.

The ability of enzymes to hydrolyze the ubiquitous polyester, poly(ethylene terephthalate) (PET), has enabled the potential for bioindustrial recycling of this waste plastic. To date, many of these PET hydrolases have been engineered for improved catalytic activity and stability, but current screening methods have limitations in screening large libraries, including under high-temperature conditions. Here, we developed a platform that can simultaneously interrogate PET hydrolase libraries of 104-105 variants (per round) for protein solubility, thermostability, and activity via paired, plate-based split green fluorescent protein and model substrate screens. We then applied this platform to improve the performance of a benchmark PET hydrolase, leaf-branch compost cutinase, by directed evolution. Our engineered enzyme exhibited higher catalytic activity relative to the benchmark, LCC-ICCG, on amorphous PET film coupon substrates (∼9.4% crystallinity) in pH-controlled bioreactors at both 65 °C (8.5% higher conversion at 48 h and 38% higher maximum rate, at 2.9% substrate loading) and 68 °C (11.2% higher conversion at 48 h and 43% higher maximum rate, at 16.5% substrate loading), up to 48 h, highlighting the potential of this screening platform to accelerate enzyme development for PET recycling.

Structural Characteristics and Dielectric Properties of Deposited Silver Nanoparticles with Polypyrrole on PET Films for Dielectric Devices

Herein, (PPy-Ag)/PET composites, consisting of silver nanoparticles (AgNPs) and polypyrrole (PPy) coated on PET, were fabricated by the polymerization process and then the films were characterized by SEM and XRD techniques. The addition of PPy-Ag on the dielectric properties of PET were determined. The XRD proved the successful synthesis of the (PPy-Ag)/PET samples. The SEM results demonstrate the effect of Ag modified the characteristics of the composite, which confirmed the interaction of (PPy-Ag)/PET. The dielectric properties of the films in frequency of 50 Hz to 5.6 MHz were measured. The density energy was enhanced from 9.1 × 10−5 for PET to 5480 × 10−5 J m−3 for (PPy-Ag)/PET. Moreover, the relaxation time τr decreased from 1.7 × 10−5 for PET to 2.8 × 109 sec for (PPy-Ag)/PET. The obtained data confirm the incorporation of PPy-Ag by PET. This research has led to the development of novel physico-chemical properties in flexible polymeric nanocomposite films, which could be used in high-performance energy storage devices.

Enhancing flexible electronics: Unveiling the role of strain rate in the performance of molybdenum-coated PET films

This work analyzes the mechanical and electrical properties of molybdenum (Mo) thin films at 100 and 200 nm thicknesses under different strain and strain rate circumstances. The study examines Mo film deposition by RF magnetron sputtering on PET substrates and their mechanical stress behavior. The investigation reveals distinct patterns of crack initiation and propagation, where primary cracks predominantly appear perpendicular to the direction of applied strain, and secondary cracks develop due to stress redistribution, displaying a complex interplay between film thickness, strain rate, and crack morphology. A key finding of this study is the observation of more advanced and irregular crack patterns in thicker films (200 nm) subjected to higher strain rates (1000 mm/min), suggesting a heightened sensitivity to mechanical stress and a more chaotic fracture process compared to thinner films or those under lower strain rates. Additionally, instances of film edge delamination, particularly under high strain conditions, highlight the challenges in maintaining film-substrate adhesion and integrity under extreme mechanical deformation. The research provides critical insights into the mechanical robustness and electrical performance of Mo thin films, emphasizing the influence of microstructural properties, deposition parameters, and external stressors on their applicability in high-tech industries. The findings underscore the importance of optimizing deposition techniques and understanding material behavior under stress to enhance the durability and reliability of Mo thin films in practical applications, ranging from semiconductor devices to photovoltaic systems.

Laser microdissection system based on structured light modulation dual cutting mode and negative pressure adsorption collection.

Laser microdissection technology is favored by biomedical researchers for its ability to rapidly and accurately isolate target cells and tissues. However, the precision cutting capabilities of existing laser microdissection systems are hindered by limitations in overall mechanical movement accuracy, resulting in suboptimal cutting quality. Additionally, the use of current laser microdissection systems for target acquisition may lead to tissue burns and reduced acquisition rates due to inherent flaws in the capture methods. To address these challenges and achieve precise and efficient separation and capture of cellular tissues, we integrated a digital micromirror device (DMD) into the existing system optics to modulate spatial light. This allows the system to not only implement the traditional point scanning cutting method but also utilize the projection cutting method.We have successfully cut various patterns on commonly used laser microdissection materials such as PET films and mouse tissues. Under projection cutting mode, we were able to achieve precise cutting of special shapes with a diameter of 7.5 micrometers in a single pass, which improved cutting precision and efficiency. Furthermore, we employed a negative pressure adsorption method to efficiently collect target substances. This approach not only resulted in a single-pass capture rate exceeding 90% for targets of different sizes but also enabled simultaneous capture of multiple targets, overcoming the limitations of traditional single-target capture and enhancing target capture efficiency, and avoiding potential tissue damage from lasers.In summary, the integration of the digital micromirror device into laser microdissection systems significantly enhances cutting precision and efficiency, overcoming limitations of traditional systems. This advancement demonstrates the accuracy and effectiveness of laser microdissection systems in isolating and capturing biological tissues, highlighting their potential in medical applications.

Two-dimensional nanocontainers with sheet structure endow epoxy resin with triple effects of oxygen barrier, anti-corrosion and corrosion inhibition

Previous coatings or barrier films have failed to focus on the combined application of oxygen barrier and long-term corrosion protection. In this paper, a two-dimensional sheet filler KCB with triple functions of anti-corrosion, oxygen barrier and corrosion inhibition was prepared by growing cerium dioxide (CeO2) on the surface of natural nanocontainer kieselguhr and adsorbing benzotriazole (BTA). Then applied KCB to epoxy resin (EP) to obtain EP/KCB composite coating. The hydroxyl group of CeO2 improves the compatibility of EP with KCB. The hydrogen bonding between BTA and KC, and the adsorption at the Ce3+ defect sites turn KCB into an impermeable physical barrier, which can form an inert protective film at the interface after the BTA later release. The experimental data show that the O2 GTR value of the EP/KCB5 composite coating is reduced by 35.88 % compared with that of the PET film. The |Z|0.01 Hz value both are as high as 1011 Ω·cm2 after immersed in 3.5 wt% NaCl solution for four months and with 3.0 MPa pure oxygen for 7 days, showing excellent potential for long-term oxygen resistance and corrosion protection. EP/KCB5 composite coating has an adhesion up to 11.63 MPa. Moreover, the BTA released in KCB chelates with the metal substrate to form an inert protective film, which further improves the anti-corrosion performance of the composite coating and has a certain self-healing ability. In summary, the EP/KCB5 composite coating shows excellent comprehensive properties, providing a new solution for long-term oxygen barrier and corrosion protection.

Direct Screening of PET Hydrolase Activity in Culture Medium Based on Turbidity Reduction.

The development of an efficient screening method for the activity of PET-degrading enzymes represents a significant technological advance in the field of enzyme research, with the potential to facilitate the advancement of enzymes for PET recycling. By examining the stable conditions of PET suspension and enzyme production conditions, we developed a method to quantify PET-degrading enzyme activity in E. coli culture medium using turbidity reduction as an indicator. High PET concentration or ionic strength caused aggregation of PET, and the best condition for activity detection was 0.5 mg mL-1 PET in 50 mM sodium phosphate pH 7.0. Preculture of E. coli increased the purity of enzyme secreted in medium. To evaluate the screening method, 720 colonies of the PET2-7M-H229X-F233X mutant library were analyzed and three candidates of high-activity mutants were obtained. The thermostability of the mutants could also be easily measured by measuring the residual activity after heat treatment. The H229T-F233M mutant showed 3.4 times higher degradation rate against PET film than the template enzyme at the initial time. The molecular dynamics simulation implied that the F233M mutation makes space for making an α helix and that the H229T mutation resolved the steric hindrance with Trp199. These mutations were speculated to change the angle of the Trp199 side chain of PET2 to an angle similar to that of the Trp185 of IsPETase, making it suitable for PET binding to the active center. Screening of activity using PET suspensions is compatible with robotic automation and is expected to be useful for validating computationally predicted mutations.

Nonlinear vibration characteristics of thermo-viscoelastic coupling of moving PET films with temperature-dependent elastic modulus

In order to improve the transport stability of roll-to-roll produced polyethylene terephthalate films (PET films) in high temperature environments, this paper investigates the nonlinear vibrational properties of moving PET films under a uniform temperature field by considering the temperature dependence of the elastic modulus. Firstly, constant tensile tests were conducted to test the elastic modulus values of PET films at different hot air temperatures, and the Wachtman model was improved to establish a temperature-dependent elastic modulus model for PET films. Secondly, based on the Kelvin-Voigt model, the nonlinear vibrational equilibrium differential equations of the system were established by applying the Bubnov-Galerkin method of discretization according to D’Alembert’s principle. Finally, numerical simulations based on the 4th-order Runge-Kutta method were carried out to analyze the effects of films width, external excitation frequency, external excitation amplitude, transfer velocity, ambient temperature, damping coefficient and viscoelasticity coefficient on the nonlinear vibration of the system. This provides a theoretical basis for the commissioning of stabilized transfer parameters for roll-to-roll production of PET films.

MXene-powered flexible smart windows for sustained bending performance

Ti3C2Tx MXene is renowned for its high conductivity and flexibility, making it ideal for various applications. This study focuses on developing flexible and durable Polymer-dispersed liquid crystal (PDLC) based smart windows using Ti3C2Tx MXene-coated PET films, demonstrating sustained bending performance over 10,000 cycles. The fabrication process involved spin-coating of MXene dispersion (average flakes size ∼400 nm) on PET film to fabricate flexible transparent conductive electrodes (TCE) having a sheet resistance (Rs) of ∼550 Ω.sq.−1 and a transmittance of ∼80 % (at 550 nm). PDLC mixture containing liquid crystals and NOA65 monomer were sandwiched within MXene electrodes to prepare PDLC-based smart windows having a transmittance of ∼75 %. UV-cured polymer contributes to mechanical stability, while the Ti3C2Tx MXene electrodes impart electrical conductivity to the smart windows. The MXene electrodes demonstrate remarkable flexibility as evidenced by a minimal change in resistance, with a strain of 0.8 % resulting in a 0.7 % change in relative resistance (∆R/Ro) at a bending radius of ∼7.5 mm. The durability of flexible smart windows was investigated till 10000 bending cycles (bending radius of ∼9.5 mm). After sustained bending the smart films maintain ON-state transmittance in the 70–75 % range. These smart windows exhibit a variation of <5 % in ΔT (difference between OFF and ON-state transmittance) and the contrast ratio after 10000 bending cycles. These smart windows feature rapid switching time (ON/OFF) along with low power consumption of ∼8 Wm−2.

Scratching of metallized polymer films by Vickers indenter as a method for controlled production of SERS-active metasurfaces

The opportunities of a system of parallel microscratches drowed on a PET film metallized with silver and copper using a Vickers indenter as an active Surface-enhanced Raman spectroscopy (SERS) or Photoluminescence-enhanced surface have been investigated. It is shown that the enhancement of the SERS signal for rhodomine is proportional to the total length of microscratches in the laser spot and increases after their application due to the relaxation of the polymer backing. The results of the microscratch geometry analysis by an atomic force microscopy and scanning electron microscopy methods indicate the probability of the location of “hot points” along the “dumps” of metal along the shores of scratches, as well as on nanoroughnesses along their inner walls.© 2017 Elsevier Inc. All rights reserved.