Kinetically controlled metal-elastomer nanophases for environmentally resilient stretchable electronics

Chae, Soosang; Choi, Won **; Nebel, Lisa Julia; Cho, Chang Hee; Besford, Quinn A.; Knapp, André; Makushko, Pavlo; Zabila, Yevhen; Pylypovskyi, Oleksandr; Jeong, Min Woo; Avdoshenko, Stanislav; Sander, Oliver; Makarov, Denys; Chung, Yoon Jang; Fery, Andreas; Oh, ** Young; Lee, Tae Il

doi:10.1038/s41467-024-47223-6

Kinetically controlled metal-elastomer nanophases for environmentally resilient stretchable electronics

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Published: 09 April 2024

Volume 15, article number 3071, (2024)
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Kinetically controlled metal-elastomer nanophases for environmentally resilient stretchable electronics

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Abstract

Nanophase mixtures, leveraging the complementary strengths of each component, are vital for composites to overcome limitations posed by single elemental materials. Among these, metal-elastomer nanophases are particularly important, holding various practical applications for stretchable electronics. However, the methodology and understanding of nanophase mixing metals and elastomers are limited due to difficulties in blending caused by thermodynamic incompatibility. Here, we present a controlled method using kinetics to mix metal atoms with elastomeric chains on the nanoscale. We find that the chain migration flux and metal deposition rate are key factors, allowing the formation of reticular nanophases when kinetically in-phase. Moreover, we observe spontaneous structural evolution, resulting in gyrified structures akin to the human brain. The hybridized gyrified reticular nanophases exhibit strain-invariant metallic electrical conductivity up to 156% areal strain, unparalleled durability in organic solvents and aqueous environments with pH 2–13, and high mechanical robustness, a prerequisite for environmentally resilient devices.

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Introduction

Nanophase mixtures serve as building blocks for functional composites because they can potentially maximize synergistic effects by leveraging the strengths of each component without any compromise^1,2,3,4. However, when combining materials that lack strong mutual interaction, thermodynamically driven phase separation hinders the blending of their chemical and physical properties^5,6,7,8. This challenge is particularly pronounced in composites of metals and elastomers for stretchable conducting membranes^8,9,10,11,12. Such membranes have long sought after properties that include metal-like conductivity, rubber-like elasticity, mechanical durability, and physicochemical resilience^{13,14,15,16,17}. Nevertheless, creating conductive metal-elastomer nanophase mixtures is challenging, as the simple physical mixing of metal nanoparticles (or nanowires)^13,14,18 with elastomer precursors or the in-situ reduction of metal nanostructures within the elastomer^19,20,21,22 have proven to be insufficient, as they result in either low electrical conductance or reduced mechanical stretchability or elasticity²³. Alternatively, intrinsically stretchable organic conductors^24,25 or extrinsically configured structures, such as wrinkled/buckled^15,26,27,28 and kirigami structures^29,30, could solve such performance issues. However, we still expect true metal-elastomer nanophases to be a superior option, especially for usage in high-profit bioelectronic applications which require high-fidelity, long-term stable operation³¹ in demanding microcosms within the human body³². This is because tailored metal-elastomer nanophases should excel in electrical performance, mechanical durability, and environmental resilience, where each characteristic is inherited from the respective metal and elastomer components. Nanoscale blending forms large interfaces that enhance the adhesion strength between metal and polymer^{Full size image}

The Raman data are consistent with the results obtained from finite element method (FEM) simulations based on hyper-elastic material models (Suppl. Note 4 and 5). Specifically, we used a hyperelastic Mooney-Rivlin material with parameters derived from uniaxial tensile tests (see Suppl. Fig. 12 and Suppl. Table 1 for the uniaxial tensile tests for the φ = 3.5 PDMS). For the plain Au layer and the Au-PDMS layer (an elastic rectangular block of dimensions of 24 µm × 24 µm × 20 µm in x-, y- and z-direction), we used two geometrically exact Cosserat shells as described in the literature⁵⁵. To model the swelling ratio, we attached a swollen plain Au layer and a swollen Au-PDMS layer to a stretched-out plain PDMS layer. After releasing the stretch on the plain PDMS layer, a 3D microstructure formed due to the stress mismatch. For all simulations, we chose the same maximum penetration depth of Au atoms as in the HRTEM images (Fig. 2a). There was almost no dependence on the deposition thickness in the case of φ = 3.5, which corresponds to our experiments.

In our computational analysis, we explored the surface morphology using three key parameters: Young’s modulus (E_Y), the swelling ratio of the Au-PDMS nanophase layer (Q), and the thickness of the top plain Au layer (t_Au). Among the various experimental conditions, in particular we focused on the effect of deposition thickness on the swelling and releasing behavior of gyrified structures. In our simulations, we assumed that that with an increase in the process time, t_process, at a fixed deposition rate, both the swelling ratio of the Au-PDMS nanophase layer, Q, and Young’s modulus, E_Y, also increase (Fig. 3d). The calculated surface morphology after stress release closely matched the experimental data in many aspects, including the shape, feature size, and general trend with increasing t_process. The transition from hexagonally arranged islands to a labyrinth pattern was confirmed when t_Au is 80 nm, Q is 1.3, and E_Y is 10 GPa, aligning well with observations in the OM images. These results support our hypothesis that the spontaneous evolution of the 3D structure is initially driven by the compressive stresses of an Au-PDMS nanophase accumulated by excessive crosslinkers. However, it is important to note that the complete replication of gyrified experimental results with deep folds in simulations was challenging using this simplified FEM model, even when scanning all possible computational parameters. This is mainly because gyrification cannot be solely induced by compressive stresses with fixed force; rather, it involves a complex dynamic process that includes chemical migrations and changes in volume and compressive force vector over time.

Based on real-time OM observations (Suppl. Movie 1), together with HRTEM morphologies and FEM simulations, we conclude that the gyrification phenomenon is initially driven by accumulated compressive stress. However, it is further influenced by the subsequent self-swelling of uncross-linked, low-molecular-weight PDMS oligomers for a couple of hours. Macroscale expansion due to the self-swelling of oligomers was observed and quantified by measuring the change in a patterned deposition area (Suppl. Figs. 13 and 14). The different nanophases exhibited variations in expansion: the reticular nanophase displayed a roughly 10% change in measured area, while the particulate nanophase showed a change in area of approximately 3% (measured by the photolithographically defined gap between before and after gyrification, Suppl. Fig. 14). Another strong piece of evidence suggesting the self-swelling of PDMS oligomers can be found by etching out metal layers after gyrification. If the nanostructures collapse after the etching process, it indicates that there were no crosslinked PDMS nanostructures but only Au nanostructures with excessive crosslinkers. However, if they maintain their gyrified morphologies even after the etching process of Au, it indicates that the PDMS oligomers themselves migrated and crosslinked to form the nanophase structures. It was observed that the gyrified PDMS structures were maintained even without the Au layer (Fig. 3e), strongly suggesting the self-swelling of oligomers as well as their crosslinking into reticular nanophases during the gyrification processes.

Elastomer-like stretchability with metal-like conductivity

As mentioned earlier, the primary goal of forming a metal-elastomer nanophase is to achieve pure PDMS stretchability while maintaining Au electrical conductivity. We argue that our Au-PDMS nanophase materials demonstrate such characteristics. In a sample with optimized parameters (1.25 mm thick PDMS membrane, φ = 3.5, Au deposition rate of 2.5 Å s⁻¹, and d of 100 nm), we observe a conductivity as high as 1.4 × 10⁴ S cm⁻¹ (Fig. 4). This initial conductivity obtained by four-point probe measurements did not change upon the application of uniaxial strain up to 150% (Fig. 4a, b, blue) or areal strain up to 156% (Fig. 4a, b, red). No mechanical failures, such as cracks or delamination, were observed during the stretching tests, confirming its rubber-like elasticity. Moreover, the initial conductivity remained constant even after 10,000 stretching–releasing cycles with uniaxial and areal strains in the same range (Fig. 4b). Additionally, it exhibits superior long-term stability, as the electrical performance remained virtually constant for more than 8 years of shelf life (Suppl. Fig. 15).

**Fig. 4: Highly strain-invariant electrical conductivity achieved by the gyrified 3D structure.**

Depending on the application, electrodes can generally be classified into two types: active and passive. Active electrodes are used to directly inject or extract currents into/from a system, while passive electrodes serve to carry currents between different components or parts of a circuit. Among these, strain-invariant electrical properties are especially important for passive bus lines, ensuring a stable and reliable conductive path within and between circuit elements. To address this importance and cater to practical applications, we studied the relative resistance of our 3D Au-PDMS nanophase samples by employing two-terminal measurements with electrode widths ranging from 1 to 5 mm (Fig. 4c).

The standout feature of our Au-PDMS nanophase is its invariance to strain, greatly surpassing other state-of-the-art materials (Suppl. Tables 2, 3, Suppl. Fig. 16)^{13,14,15,24,25,56}. The “ideal elastic conductor” in Fig. 4c depicts a hypothetical sample with strain-invariant resistivity in two-terminal measurements, only portraying the geometric change in resistance that would come with stretching, including considerations regarding Poisson’s ratio (Suppl. Fig. 17). Under this condition, the calculated resistance increases by 2.5 times at 100% uniaxial strain (calculation details in Suppl. Note 6). Comparing this to the measured resistance changes of our Au-PDMS, we arrive at a compelling result: even up to 30% uniaxial strain, the resistance changes of our samples were significantly lower than those of an ideal elastic conductor. This intriguing behavior comes from the unfolding of the 3D gyrified structures upon stretching, effectively compensating for the increased resistance due to dimensional changes.

The experimental and calculated resistance changes under areal strain showed the same tendency, where the Au–PDMS 3D nanophase samples exhibited a smaller resistance change than an “ideal elastic conductor” with up to 156% areal strain (Fig. 4d, Suppl. Fig. 18). Note that areal strain, in this context, is different from biaxial strain, as areal strain involves 3D stretching using a sphere, while biaxial strain is limited to stretching within a 2D plane (Suppl. Table 3). The unprecedented characteristics of our Au-PDMS nanophase material is primarily attributed to both the inherent stretchability of the reticular nanophases as well as the auxetic nature of the extrinsically gyrified 3D morphology (Suppl. Fig. 19). The combination of these intrinsic and extrinsic properties provides the high adhesivity and the structural, electrical elasticity required to prevent delamination and deterioration of electrical conductance in composite materials. Our view is further supported by the high gyrification index of 1.75 calculated in our samples, which is defined as the ratio of the actual surface area to the projection area (Fig. 4e).

Environmental durability for soft electronics

Following the electrical and mechanical properties of our gyrified reticular Au-PDMS nanophase samples, we showcase their multifaceted performance for applications in environmentally resilient soft electronics. Our samples display excellent stability against pH, chemical, and thermal exposure, as well as mechanical abrasion (Fig. 5a and Suppl. Note 7). After immersion in various polar and non-polar solvents (water, ethanol, acetone, chlorobenzene, and toluene) for 1 day, the conductivity of the nanophase samples slightly decreased, especially in organic solvents. This is possibly because of the deformed conduction network that comes from the swelling of the PDMS matrix itself. However, after the nanophases were dried, the conductivity almost fully recovered to within a 5% margin of error. Meanwhile, the conductivity was preserved under harsh pH conditions (pH 2–13), demonstrating this material’s suitability for bioelectronics applications in the stomach (pH 1.3–3.5) as well as for use on skin wounds (pH 7.2–8.9) (Fig. 5b). The conductivity of the gyrified Au–PDMS reticular nanophases was also almost fully maintained during adhesive tape tests (ranging from 16 to 32 N cm⁻¹) for 500 cycles (Fig. 5c). Even after an abrasion test using an eraser (Suppl. Fig. 20 and Suppl. Movie 3), the conductivity remained in the same order of magnitude (red in Fig. 5c). In contrast to other thermoplastic elastomer-based stretchable electrodes, the gyrified Au–PDMS nanophases also showed excellent thermal stability up to 250 °C for 2 h (Fig. 5d). This expands their potential use in interfacing with functional elements that require thermal annealing during fabrication and operation at elevated temperatures, such as thermoelectric and heater modules, or during hydrothermal sterilization processes (Suppl. Movie 4, and Suppl. Fig. 21).

**Fig. 5: Multimodal stability of the 3D structure of Au–PDMS nanophases.**

Furthermore, we also verified the reliability of the standard lithography processes for the gyrified Au-PDMS nanophase (Fig. 5e, f). The chemical (organic solvents) and thermal (annealing processes for photoresists) durability of the Au–PDMS nanophase samples enabled microscale patterning down to a 20 μm feature size using conventional photolithography with complex circuit designs (Suppl. Figs. 22, 23). The Au–PDMS nanophase samples were also found to be washable in a laundry machine. The initial conductivity and stretchability showed almost no change even after 20 cycles of 15 min. washing with detergent (Fig. 5g, Suppl. Fig. 24, Suppl. Movie 5). These findings imply that this stretchable conducting membrane can be used to produce lithographically defined, functional devices intended for repeated use with reliable operation in the field of wearable electronics for virtual reality (Suppl. Note 8, Suppl. Figs. 25, 26, and Suppl. Movie 6), including educational and medical applications.

Our 3D structure of Au-PDMS nanophases holds considerable appeal as a stretchable conducting membrane for soft and bioelectronics applications and may find extensive use in various fields, including biomonitoring within the digestive tract, multimodal implantable devices like ocular prostheses, soft robotics employing mechanical strain-gated logic gates, and functional fabrics for space exploration.

Methods

Kinetically controlled metal–elastomer nanophases

For the preparation of PDMS membranes, a mixture of two components, prepolymer PDMS and linker PDMS (Sylgard 184, Dow Corning), was blended with varying ratios (φ = 2–20). The mixture was subsequently thermally cured at 80 °C for 4 h. The PDMS membranes were affixed onto sample holders within a physical vapor deposition chamber manufactured by iNFOVION. To prevent any potential evaporation of small molecules within the PDMS slab, we maintained a consistent vacuum pressure for all samples. Gold (Au, 99.9999%) was deposited using thermal evaporation at room temperature, with a constant base pressure of 1.0 × 10⁻⁶ Torr. The in-situ deposition rate and amount were monitored using a quartz crystal microbalance. The deposition rate of Au was maintained at 2.5 Å s⁻¹ for all samples, except for samples with varying deposition rates (ranging from 10 Å s⁻¹ to 0.5 Å s⁻¹). A pre-deposition step was conducted for 1 min at a constant rate of 2.5 Å s⁻¹, with the shutter closed. The main deposition phase commenced by opening the shutter and continued for 400 s, resulting in the formation of a nanophase that exhibited optimal stretchable electrode performance. Following deposition, the samples were promptly removed from the chamber and allowed to age for 6 h in ambient air. Subsequent characterization and analysis were performed without any additional surface treatments.

According to the materials safety data sheets (MSDS) for the prepolymer PDMS, it includes 0.5 wt% xylene, 0.2 wt% ethylbenzene, >60 wt% dimethylvinyl-terminated dimethyl siloxane, 30–60 wt% dimethylvinylated and trimethylated silica, and 1–5 wt% tetra(trimethylsiloxy) silane. Meanwhile, the MSDS for the Sylgard 184 “Curing Agent” indicates 0.19 wt% xylene, <0.1 wt% ethylbenzene, 55–75 wt% dimethyl, methyl hydrogen siloxane, 15–35 wt% dimethylvinyl-terminated dimethyl siloxane, 10–30 wt% dimethylvinylated and trimethylated silica, and 1–5 wt% tetramethyl tetravinyl cyclotetrasiloxane⁵⁷. Additionally, a siloxane complex containing a few wt% Pt may be present in the curing agent as a catalyst, which we believe plays the most important role in crosslinking. However, the exact concentrations are unknown. Given these conditions, we believe that most experimentalists would agree that core components of prepolymer and crosslinker, would include difunctional vinyl-terminated PDMS chain as the prepolymer, where crosslinking occurs via the SiH-containing, a low molecular weight trimethylsiloxy-terminated PDMS with platinum catalysts assisting the formation of a siloxane cross-linking network⁵⁸.

The viscosity of the prepolymer and the mixture immediately after mixing with the curing agent is 5500 mPa s and 4000 mPa s, respectively. For reference, the molecular weight of Sylgard 184 has been reported to be about M_n ≈ 4500 g mol⁻¹ and M_w ≈ 19,000 g mol⁻¹ (PI = 4.24) in literature⁵⁹. M_n and M_w denote the number-averaged and weight-averaged molecular weight, respectively, and PI is the polydispersity index.

Stretching performance, mechanical and optical characterization

To uniformly apply uniaxial and areal strain to the 3D structure of Au-PDMS nanophases samples, a custom-made 1-D and 2-D screw-based stretching apparatus was integrated with an optical microscope (BX-51P, Olympus), confocal microscope, and a four-point probe station (Loresta-GP MCP-T600, MITSUBISHI CHEMICAL) for electrical property measurements. The strain rate used for the strain-dependent conductivity measurements was set at 10% s⁻¹. Cyclic stretchability, tested up to 10,000 cycles, was assessed using a stretching machine (Flexible Materials Tester, Hansung Systems, Inc.). For viscoelasticity measurements, dynamic mechanical analysis (DMA) was conducted using a TA Instrument Q800 instrument with a gas cooling accessory and a fiber/film tension modulus. Young’s modulus of both plain PDMS and the 3D structure of Au-PDMS nanophases samples was determined using a MultiXtens II HP instrument from Zwick, following the DIN 53504/S2/30 protocol. The gyrification index was determined from the data acquired through laser scanning confocal microscopy (LSM, Olympus LEXT OLS4100 laser scanning digital microscope). UV–Visible spectra of the samples were obtained using V-770 UV-Visible/NIR spectrophotometer. Raman map** was obtained from Raman spectra (LabRam Aramis, Horiba Jovin Yvon) of the samples in 10 μm × 10 μm area.

TEM characterization

For the cross-sectional TEM images, PDMS samples were prepared as lamellar thin slices using focused ion beam (FIB) techniques with the JIB-4601F instrument from JEOL and the Quanta 3D FEG instrument from FEI. Subsequent TEM analysis was performed using a JEM-ARM 200F microscope from JEOL. To generate the 3D TEM tomography image of the Au-PDMS nanophases in the sample, a series of tilted TEM images (30 images in total) were acquired by rotating the sample holder from −21° to 66°. This process was carried out at a magnification of 50,000 with an exposure time of 0.5 s using a CCD camera (Orius SC200D, Gatan) mounted on an Ultra Corrected Energy Filtering Transmission Electron Microscope (UC-EF-TEM) system (Libra 200 MC TEM, Carl Zeiss). The acquired images were then subjected to an image reconstruction process, specifically Filtered Back Projection (TEMography), to generate the final 3D image.

NMR characterization

The modulation of non-covalently tethered PDMS molecules within the PDMS matrix can be achieved by adjusting the prepolymer to crosslinker ratio. To characterize the residual solvent within the PDMS matrix, a series of free-standing PDMS membranes were immersed in CDCl₃ for ¹H nuclear magnetic resonance (NMR) analysis, allowing us to track the presence of uncrosslinked PDMS over time. Freshly cured PDMS membranes, prepared with varying φ values, were sectioned into 4 × 5 × 10 mm³ pieces and placed in an air-tight vessel containing 1.2 mL of CDCl₃ (Eurisotop) for overnight incubation. Due to higher adsorption of the solvent by PDMS membranes with lower φ, an additional 0.8 mL of CDCl₃ was added after 60 min. Subsequently, a portion of each sample’s supernatant was collected for ¹H NMR measurements (500.13 MHz) using an AVANCE III 500 Spectrometer (Bruker, Germany) at a temperature of 30 °C.

Micropatterning for integrated circuit

The photolithography of the Au-PDMS nanophase samples was conducted following standard procedures. Specifically, the sample was spin-coated with a positive photoresist (positive AZ 5214E®, MicroChemicals) and then subjected to a soft bake at 110 °C for 2 min. Subsequently, the sample was exposed to a 365-nm UV light source (KLS-100H-LS−150P, DONGWOO Optron) using a patterned photomask. After exposure, the sample was immersed in a developer solution (AZ® 327, MicroChemicals) with vigorous shaking for 1 min. A post-bake step at 190 °C for 10 min was performed to ensure complete curing of the residual photoresist. Selective etching of the nanophase was achieved by incubating it in aqua regia, a mixture of HCl and HNO₃ in a 9:1 volume ratio. Any remaining photoresist was removed using a universal photoresist stripper (AZ® 100, MicroChemicals) for lift-off. For stencil mask lithography, a metal stencil mask (0.1 mm thick stainless steel, Devora Electronics) was placed directly on a plain PDMS membrane (φ = 3.5, thickness 0.65 mm) without a spacer.

Environmental resilience test

To assess chemical stability, the as-fabricated 3D structure of Au-PDMS nanophase samples were immersed in various solvents (water, ethanol, acetone, c-Benzene, and toluene) overnight, followed by conductivity measurements (marked as “incubation” in the “Organic solvent” section of Fig. 5a). Subsequently, the samples were deswelled at 60 °C overnight, and the conductivity was measured again (marked as “drying” in the “Organic solvent” section of Fig. 5a). For pH stability testing, solutions of HCl and KOH were used to create different pH conditions. The as-fabricated samples were then immersed in the respective pH solutions for varying durations (up to 10,000 min). In the tape adhesion test, a strong adhesive tape (3 M) was repetitively attached and detached from the surface of the 3D structure of Au-PDMS nanophases for 500 cycles. The conductivity change was measured after each attachment cycle. In the eraser test, the surface of the as-fabricated Au-PDMS nanophases was repeatedly rubbed with a pencil eraser (TOMBOW®) for a specified number of cycles. The rubbing strength was determined by the specific contact area (2 cm × 2 cm) and the applied push force, which was ~0.245 kPa, a force sufficient to generate eraser dust. This procedure was recorded in Suppl. Fig. 20 and Suppl. Movie 3. Thermal stability trials were performed by heating the samples on a hot plate (SMHS-3, DAIHAN). The conductivity of the samples was evaluated after annealing at various temperatures. For the laundry test, the sample (without encapsulation) was subjected to washing both with and without detergent (Persil Gel Detergent, Germany) in a washing machine (WW70T4042EE/EG, Samsung) for 15 min at room temperature. This washing procedure was repeated 20 times for the cyclic washing test.

Data availability

The data that support the findings of this study are available from the corresponding authors upon request.

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Acknowledgements

This research was supported by the National Research Foundation of Korea (NRF) (2021R1C1C1009925, 2020R1A6A1A03048004, and 2019R1A6C101052) and funded by the Korea Evaluation Institute of Industrial Technology (KEIT) (20015898, 20012710 and 20019105). This work was also supported by the Korea Institute for Advanced Technology (KIAT), the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea (nos. P0017363), and the GRRC program of Gyeonggi province (GRRCKYUNGHEE2023-B03). We thank the Korea Basic Science Institute (KBSI) for the technical support. We gratefully acknowledge Anik Kumar Ghosh, Uta Reuter, and Petr Formánek for assistance with FEM simulations, FIB, and TEM analysis, respectively. We thank Jeeho Park, Minji Cho, and Hyemin Park for assistance with image processing, as well as Jonas Schubert and Duwon Jeong for fruitful discussions. A.F. and S.C. acknowledge support from Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) within SPP 2100, project number 359715917; A.F., A.K., O.S., and L.J.N. acknowledge support from Deutsche Forschungsgemeinschaft (DFG) within project number 386450667. This research was also performed within project LaSensA under the M-ERA.NET scheme and was funded by the Saxon State Ministry for Science, Culture, and Tourism (Germany) and co-financed with tax funds on the basis of the budget passed by the Saxon state parliament and funded by the Deutsche Forschungsgemeinschaft (DFG)- CRC−1415 - 417590517. S.C. and A.F. acknowledge support from the German Science Foundation with SPP 2100, project number 404941515. German Research Foundation grant 600/20−1 640690U12AB123456 (L.J.N.). This work is financially supported in part by German Research Foundation (DFG) grants MA 5144/13−1, MA 5144/28−1, European Commission HORIZON RIA (project REGO; ID: 101070066) and Helmholtz Association of German Research Centres in the frame of the Helmholtz Innovation Lab “FlexiSens”. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. W.J.C. gratefully acknowledges the LLNL LDRD Programs for funding support of this project under No.22-ERD-056 and 24-LW-035. This work was also supported by a Korea University grant.

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These authors contributed equally: Soosang Chae, Won ** Choi.

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Leibniz-Institut für Polymerforschung Dresden e.V., Institute of Physical Chemistry and Polymer Physics, Hohe Str. 6, 01069, Dresden, Germany
Soosang Chae, Quinn A. Besford, André Knapp & Andreas Fery
School of Energy Materials and Chemical Engineering, Korea University of Technology and Education, Cheonan, 31253, South Korea
Soosang Chae
Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA, 94550, USA
Won ** Choi
Institut für Numerische Mathematik, Technische Universität Dresden, Zellescher Weg 12–14, 01069, Dresden, Germany
Lisa Julia Nebel & Oliver Sander
Department of Materials Science and Engineering, Gachon University, Seong-nam, Gyeonggi 13120, Republic of Korea
Chang Hee Cho & Tae Il Lee
Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328, Dresden, Germany
Pavlo Makushko, Yevhen Zabila, Oleksandr Pylypovskyi & Denys Makarov
Kyiv Academic University, 03142, Kyiv, Ukraine
Oleksandr Pylypovskyi
Department of Chemical Engineering (Integrated Engineering Program), Kyung Hee University, Yongin, 17104, Republic of Korea
Min Woo Jeong & ** Young Oh
Leibniz-Institut für Festkörper- und Werkstoffforschung e.V., Institute for Solid State Research, Nothnitzer Str. 49A, 01069, Dresden, Germany
Stanislav Avdoshenko
Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
Yoon Jang Chung
Technische Universität Dresden, Mommsenstr. 4, 01062, Dresden, Germany
Andreas Fery

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Soosang Chae
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Contributions

J.Y.O., S.C., W.J.C., and T.I.L. contributed to conceptualization. J.Y.O., S.C., Q.A.B., L.J.N., A.K., C.H.C., P.M., Y.Z., S.A., O.P., and T.I.L. were involved in develo** and defining the methodology. S.C., J.Y.O., W.J.C., D.M., Q.A.B., L.J.N., A.K., C.H.C., P.M., Y.Z., S.A., O.P., and T.I.L. conducted the investigation. S.C., J.Y.O., Q.A.B., L.J.N., C.H.C., P.M., Y.Z., S.A., O.P., T.I.L., and M.W.J. handled visualization tasks. J.Y.O., D.M., T.I.L., W.J.C., and A.F. led funding acquisition efforts. J.Y.O., D.M., T.I.L., W.J.C., and A.F. managed the project administration. J.Y.O., D.M., W.J.C., A.F., O.S., S.A., and T.I.L. supervised the project. J.Y.O., S.C., W.J.C., D.M., Q.A.B., Y.J.C., and T.I.L. participated in writing the manuscript.

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Correspondence to Won ** Choi, ** Young Oh or Tae Il Lee.

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Chae, S., Choi, W.J., Nebel, L.J. et al. Kinetically controlled metal-elastomer nanophases for environmentally resilient stretchable electronics. Nat Commun 15, 3071 (2024). https://doi.org/10.1038/s41467-024-47223-6

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Received: 29 November 2023
Accepted: 23 March 2024
Published: 09 April 2024
DOI: https://doi.org/10.1038/s41467-024-47223-6
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Materials science and chemistry

Focus 26 January 2021

Kinetically controlled metal-elastomer nanophases for environmentally resilient stretchable electronics

Abstract

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Introduction

Elastomer-like stretchability with metal-like conductivity

Environmental durability for soft electronics

Methods

Kinetically controlled metal–elastomer nanophases

Stretching performance, mechanical and optical characterization

TEM characterization

NMR characterization

Micropatterning for integrated circuit

Environmental resilience test

Data availability

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