Three-Dimensional Flexible All-Organic Conductors for Multifunctional

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Three-dimensional Flexible All-Organic Conductors for Multifunctional Wearable Applications In Kyu Moon, Seonno Yoon, Hee Uk Lee, Seung Wook Kim, and Jungwoo Oh ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.7b10181 • Publication Date (Web): 25 Oct 2017 Downloaded from http://pubs.acs.org on October 28, 2017

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ACS Applied Materials & Interfaces

Three-dimensional Flexible All-Organic Conductors for Multifunctional Wearable Applications In Kyu Moon,† Seonno Yoon,‡ Hee Uk Lee,§ Seung Wook Kim,*§ and Jungwoo Oh*‡ †

Yonsei Institute of Convergence Technology, Yonsei University, Yeonsu-gu, Incheon 21983,

Republic of Korea ‡

School of Integrated Technology and Yonsei Institute of Convergence Technology, Yonsei

University, Yeonsu-gu, Incheon 21983, Republic of Korea §

Development of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul

02855, Republic of Korea *E-mail: [email protected]; [email protected]

KEYWORDS: conducting polymers, all-organic devices, wearable electronics, thermal managements, all-solid-state supercapacitors.

ACS Paragon Plus Environment

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ABSTRACT: Wearable textile electrodes based on π-conjugated polymers are appealing alternatives to carbon fabrics, conductive yarns or metal wires because of their design flexibility, low cost, flexibility and high throughput. This provides the benefits of both electronics and textiles. Herein, a general and new method has been developed to produce tailorable, wearable energy devices that are based on three-dimensional (3D) poly(3,4-ethylenedioxythiophene) (PEDOT)-coated textile conductors. To obtain the desired electrode materials, both facile solution-dropping polymerization methods are used to fabricate a 3D flexible PEDOT conductor on cotton textile (PEDOT/textile). PEDOT/textile show a very low sheet resistance of 4.6-4.9 Ω⋅sq-1. Here, we employ the example of this 3D network-like structure and the excellent electrical conductivities under the large deformation of PEDOT/textiles to show that wearable and portable heaters have immense potential. A flexible textile heater with a large area (8 × 7.8 cm2) reached a saturation temperature of ∼83.9 °C when a bias of 7 V was applied for ∼70 s due to the good electrical conductivity of PEDOT. To demonstrate the performance of all-solid-state supercapacitors, nano-ascidian-like PEDOT (PEDOT-NA) arrays was prepared via a simple vapor-phase polymerization of 3,4-ethylenedioxythiophene (EDOT) on PEDOT/textile to increase both the surface area and the number of ion diffusion paths. The PEDOT-NA arrays on PEDOT/textile showed outstanding performance with an areal capacitance of 563.3 mF⋅cm-2 at 0.4 mA⋅cm-2 and extraordianry mechanical flexibility. The maximum volumetric power density and energy density of the nanostructured PEDOT on the textile were 1.75 W·cm-3 and 0.0812 Wh·cm-3, respectively. It is expected that the wearable nanostructured conducting polymers will have advantages when used as structures for smart textronics and energy conversion/storage.


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INTRODUCTION The interest in electronic textiles has recently increased significantly, as has the need for advanced wearable devices using supercapacitors,1 cooling and heating elements,2 and strain sensors.3 Due to their excellent flexibility, textiles have previously been employed as templates for the synthesis of nanoscale materials used in yarn-based transistors, integrated woven circuits, flexible circuit boards, human monitoring sensors, therapy heating, etc. In addition, their unique 3D porous structure allows textiles to achieve very high storage capacities per unit area when used as supercapacitor and/or lithium-ion battery materials. To begin with, the use of traditional metal wires for interconnections or metal coatings in/on textile has been demonstrated to be effective. However, they can cause devices to crack and peel under bending and abrasion, and they are heavy, uncomfortable, rigid, and ultimately inappropriate for textile integration. Researchers have recently attempted to fabricate flexible supercapacitors and/or thermal management components based on textile electrodes prepared by directly coating electrical carbon materials such as carbon nanotubes, graphenes, and/or silver nanowires onto the textile fiber surface using a solution process. Therefore, many approaches have been developed to fabricate an electrochemically active material on commercial textiles in an attempt to improve the supercapacitive performance of textile-based energy-storage devices. These efforts have included the fabrication of single-walled or multi-walled carbon nanotube-coated textiles,4-8 graphene- or reduced graphene oxide-coated textiles,9-13 carbonized cotton textiles,14-18 textilecoated metals,19-26 and π-conducting polymer-coated textiles with or without nanostructured electroactive materials (e.g., MnO2).24,27,28 Compared to conductive yarns, these two-dimensional textile fabrics for electrochemical electrodes simplify integration.4,29 Although there are still many challenges for implementing the new electrodes in textile energy systems, the above


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pioneering works in textile supercapacitors and electronics have opened new windows of opportunity. However, these applications based on various electronic elements suffer from limitations. These include complicated/time-consuming processes and differences in the textural characteristics of the electronic elements and textiles. In addition, nano-carbon coated onto a textile surface has lower capacitance and energy density due to its electric-double-layer capacitance. Thus, most studies of nanostructured transition metal oxides (pseudocapacitance) on carbon-based textiles have been focused on higher energy density because of their rich redox reactions and controllable morphologies. To solve these problems, several researchers have searched for alternatives to conventional methods (e.g., conducting polymers,3 carbon nanotubes,30 and graphene).31-32 Especially, π-conjugated polymers uniquely balance both mechanical properties and solution-processability, offering design engineers exceptional flexibility, freedom and workability. Among the various applications using π-conjugated polymers coated on textiles, thermal management devices (known as “Joule heaters”) and supercapacitors are the most promising candidates for wearable energy transformation and storage devices because of their relatively low cost, solution processability, and ease of use for continuous and large-scale production, as well as both their intrinsic high electrical conductivities and electrochemical properties. The EDOT monomer-based PEDOT is the most known and widely used conducting polymer for supercapacitors. Its benefits include its redox activity, high conductivity (10-4–103 S·cm-1),33-38 chemical/thermal/environmental stability, various possible compositions, high intrinsic flexibility, and compatibility with aqueous electrolytes.39,40 Smart and electronic textiles that combine electronics with economically viable cotton or synthetic textiles are of great interest, as they offer many possibilities for wearable


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technology.4,19,41-46 Textiles are 3D nano/microstructures with many voids, thus forming a porous material. In this work, we report the coating of lightweight, freestanding, single PEDOT electrodes prepared by all-solution-processed polymerization directly onto a 3D commercially available cotton textile. We also explore for the possibility of fabricating heating textiles and flexible all-solid-state supercapacitors with this process. The sheet resistance of PEDOT on the textile was between 4.6 and 4.9 Ω·sq-1. A flexible textile heater based on PEDOT is demonstrated across a wide operating temperature range (up to ∼83.9 °C under 7 V within ∼70 s: active area ∼8 cm × 7.8 cm). Nanostructures with appropriate shapes can be used to circumvent the surface area problem. The morphological structure of the electrode materials also plays an important role in the electrochemical performance of supercapacitors. We therefore synthesized PEDOT-NA arrays on the PEDOT/textile via vapor-phase polymerization of EDOT to increase both the surface area and the number of ion diffusion paths. The PEDOT-NA/PEDOT/textile material was applied as all-solid-state supercapacitors using a H2SO4-polyvinyl alcohol (PVA) gel as the electrolyte employed in flexible energy storage devices. The unique structure of the 3D PEDOT-NA/PEDOT/textile exhibited synergistic characteristics of high accessibility to the electrolyte, a short solid-state diffusion length for SO3ions, and high conductivity, which resulted in an ultrahigh areal capacity of up to 563.3 mF·cm-2 at a current density of 0.4 mA·cm-2. The 3D PEDOT/textile also exhibited a high power density (31.19 W·cm-3 at an energy density of 0.681 Wh·cm-3) with superior flexibility.


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RESULTS AND DISCUSSION Figure 1a shows a schematic of the synthesis of 3D PEDOT-NA arrays on the PEDOT/textile network structure using a two-step process. The PEDOT-wrapped cotton fabric was prepared by in-situ chemical oxidative polymerization at room temperature.29 Briefly, 1.86 mM of iron perchlorate in isopropyl alcohol (IPA) was placed directly onto cotton fabric, which was then dried at room temperature. The Fe(ClO4)3-coated textile was then used as an oxidant to initiate the polymerization of EDOT monomers. A solution of 0.46 mM of EDOT in IPA was dropped directly onto the Fe(ClO4)3-coated textile and allowed to dry and polymerize at room temperature. After approximately 2 h, the textile was washed several times with IPA and dried for 12 h at room temperature. We then performed this procedure four more times. The mass loading of PEDOT on the textile was ∼8.6 mg·cm-2. To further increase the volumetric capacitance, PEDOT-NA arrays on PEDOT/textile were synthesized through vapor-phase polymerization using a modified D’Arcy’s method.47 To synthesize PEDOT-NA arrays on the PEDOT/textile, the PEDOT/textile was impregnated with a 20 wt. % FeCl3–methanol solution and dried in air to facilitate the adsorption of FeCl3. After the FeCl3-coated PEDOT/textile was exposed to EDOT vapor at 70 °C for 4 h under a pressure of ∼0.1 Torr, the absorbed FeCl3 triggered the vaporphase polymerization (VPP) of EDOT. The PEDOT-NA arrays on the PEDOT/textile will be

discussed

further

in

terms

of

both

their

morphology

and

all-solid-state

supercapacitance behavior in subsequent sections. The morphology of the PEDOT/textile conductor was investigated through scanning electron microscopy (SEM). Figures 1b–d show low- and high-magnification SEM


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images of the PEDOT/textile conductor. For reference, an image of the bare cotton fabric is provided as Figure S1 in the Supporting Information, showing a smooth, fibrous surface. Following EDOT polymerization, the cotton fabric yarns’ surfaces were coated completely. PEDOT penetration into the microstructure of the fabric did not destroy the cotton fabric’s structural integrity. In addition, the as-prepared PEDOT/textile exhibited partial overlapping of PEDOT-coated cotton yarns in 3D space, thus an interconnected porous network between PEDOT-coated yarns (PEDOT/yarns) existed. Some areas on the PEDOT/yarns were coated by small granular PEDOT. The PEDOT/textile was subjected to energy-dispersive X-ray spectroscopy (EDS) analysis to identify the type and distribution of elements residing on the fabric surface. The presence of C, O and S elements in the PEDOT/textile and lack of Fe or Cl elements is also confirmed by EDS analysis (Figure 1f-i). By using VPP to obtain novel hierarchical PEDOT-NA arrays on the 3D PEDOT/textile, the energy-related area of the PEDOT/textile conductors was enlarged(Figure 2a). Due to their high specific surface area and large surface-to-volume ratio, which allows for effective contact with the electrolyte ions, these nanostructured arrays are promising electrode materials for supercapacitors. After the VPP-based PEDOT deposition on the PEDOT/textile, the PEDOT-NA arrays fully covered the PEDOT/textile with relatively large-diameter nanostructures. The PEDOT nanostructures also showed some structural defects, e.g., PEDOT nanobelts and nanowires, indicated in the sky-blue circles of Figure 2a and Figure S2 (Supporting Information). These various PEDOT nano-morphologies on 3D PEDOT/textile may be due the diffusion-rate of vapor-phase EDOT during polymerization into the anisotropic FeCl3 template as both a seed template and nucleation sites. The diameter, length, and lateral cavities of the


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PEDOT-NA arrays (based on the SEM images) were ∼264 ± 0.06, ∼208 ± 0.05, and ∼166 ± 0.05 nm, respectively. In addition, EDS analysis showed that the C/S ratio in the PEDOT-NA arrays was ∼6.3, as shown in Figure 2e, which is not far off the theoretical value of 6.0.47 Furthermore, EDS elemental mapping (Figures 2f–h) was carried out to analyze the distribution of each representative element of the PEDOT-NA arrays. The homogeneous distribution of C, S, and O elements across the entire surface of the PEDOT-NA arrays and the presence of a small amount of Cl- from FeCl3 were confirmed by this elemental EDS mapping.47,48 This alignment of PEDOT-NA arrays not only makes it easier for the electrolyte to penetrate the electrode but also improves the mechanical tolerance to volumetric changes during cycling. The chemical structures of the PEDOT/textile and PEDOT-NA/PEDOT/textile materials were first characterized using Fourier transform infrared (FTIR) spectroscopy, with results shown in Figure 3a. In Figure 3a, the bands represent the functional groups of various compounds available in PEDOT, such as C–S, C=C, C–S, and the ethylenedioxyl group. The absorptions at 987, 935, 854, and 698 cm-1 were assigned to the vibration modes of the C–S bond in the thiophene ring,29,47,48 whereas the absorption peaks at 1255, 1147, and 1110 cm-1 were assigned to the ethylenedioxyl group. The other absorption peak at 1552 cm-1 is attributable to the stretching mode of C=C originating from the thiophene ring. The Raman spectra (λmax = 532 nm) of PEDOT/textile and PEDOT-NA/PEDOT/textile are almost identical, verifying that both solution polymerization and VPP of EDOT resulted in the formation of PEDOT (Figure 3b and Figure S3a in Supporting Information). We assigned the main bands in the Raman spectra of PEDOT/textile and PEDOTNA/PEDOT/textile to the asymmetric (1493/1499 cm-1) and symmetric (1434/1435 cm-1)


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Cα=Cβ stretching vibrations and the Cα–Cα inter-ring stretching vibrations. In addition, the establishment of the benzenoid and quinoid ring vibrations at approximately 1440 cm1

and 1415 cm-1, respectively, was enabled by band fitting by the superposition of

Gaussian lines.29,49 The X-ray diffraction pattern of PEDOT/textile is presented in Figure S4. Two peaks characteristic for PEDOT were observed, with the most intense peak, centered at 2θ = 26.16° ascribed to the (020) reflection of PEDOT, attributed to interchain planar ring stacking. A second Bragg diffraction peak, centered at 2θ = 6.68°, could be due to the periodicity of PEDOT’s parallel and perpendicular polymer chains or the (100) reflection.29 X-ray photoelectron spectroscopy (XPS) was used to study the quantitative elemental compositions and chemical states of our samples. Comparative general scan spectra of PEDOT/textile and PEDOT-NA/PEDOT/textile are shown in Figure S3b of the Supporting Information. The survey scan XPS profiles of PEDOT/textile and PEDOT-NA/PEDOT/textile show signatures for C1s and S2p (Figures 3c and d). The deconvoluted C1s XPS profile of each PEDOT sample shows peaks positioned at 284.7 eV for C=C/C–H, 286.2 eV for C–S, 287.2 eV for C–O, and 288.6 eV for C–Cl.29,50 The characteristic peaks of the S 2p core-level spectra of PEDOT/textile and PEDOT-NA/PEDOT/textile were also recorded at 284.45 eV and 285.3 eV, with the former corresponding to the binding energy of C=C/C–C and the latter corresponding to the binding energy of sp3C. The other peaks at binding energies of 286.44, 287.9, and 288.9 eV could be attributed to C–O, C=O, and O–C=O functionalities, respectively. As shown in Figure 3d, the S 2p region was deconvoluted into four peaks corresponding to the following binding energies: 163.7, 164.9, 166.2, and 167.4 eV. The first two were assigned to S3/2 and S1/2 of neutral sulfur, while the second two were assigned to S+, clearly showing that PEDOT is in the


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doped state.51 Furthermore, both the O 1s and Cl 2p spectra of each PEDOT sample are displayed in Figures S3c and d (Supporting Information). The FTIR, Raman, and XPS results therefore indicate that the polymerization of EDOT to PEDOT was successfully performed on the textile surfaces. Electrical conductivity is a crucial factor for electrochemical electrodes and/or current collectors. As expected, the Rsh decreased with an increase in the number of polymerization layers, as shown in Figure 4a and Figure S4 (Supporting Information). However, after washing with IPA following polymerization, the Rsh increased. For example, the Rsh of the textile after the first coating of PEDOT dramatically increased from 13 Ω·sq-1 to 24 Ω·sq-1, an increase of 84.6 %, due to the washing away (dedoping) of excess negatively charged perchlorate monomers from the positively charged PEDOT chains by the IPA treatment. However, PEDOT/textile remained conductive after each wash cycle. Although the Rsh of PEDOT-coated textile was high after the first layer (24 Ω·sq-1), it significantly decreased to 3 Ω·sq-1 after five successive coating cycles. As the number of coatings increased, the density and thickness of the PEDOT wrapped around the textile fibers increased as well, resulting in a much lower electrical resistance. The uniformity of Rsh is a parameter for solution processing and large-area roll-to-roll fabrication. To evaluate the uniformity of the obtained PEDOT/textile, 400 locations on 10 × 10 cm2 of PEDOT/textile were selected (in a 2D array with a 0.5 cm2 lattice) and measured using the four-probe method. On the contour diagram of PEDOT/textile, shown in Figure 4b, the spatial distribution of Rsh ranged from 4.2 Ω·sq-1 (marked as black) to 5.5 Ω·sq-1 (marked as bright blue). Surprisingly, among the colors on the surface area, the dark-blue color with low resistance was uniformly distributed, suggesting that Rsh was between 4.6 and 4.9 Ω·sq-1. As two essential parameters for flexible electronic-textile


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conductors, the conductivity and mechanical properties of as-fabricated PEDOT/textile were also evaluated. Figure 4c displays the typical current-voltage (I–V) curves of the PEDOT/textile with different states of mechanical deformation including flat, bent, and twisted. As shown in Figure 4c, the PEDOT/textile was flexible without incurring a reduction of its transport properties under different bending and twisting conditions in ambient air. The curves are linear, indicating that conduction was similar to that of metal. The average resistances of flat, bent, and twisted PEDOT/textile were calculated to be 15.20, 15.48, and 15.55 Ω, respectively. The electromechanical stability of the PEDOT/textile was also studied. The electrical resistance changes that occur under mechanical bending are expressed as R/R0. Here, R0 denotes the initial resistance in a flat state, while R denotes the resistance in a bent state. Figure 4d shows the resistance change of the PEDOT/textile conductors during repeated bending (Figure 4d, top axis) and at different bending angles (Figure 4d, bottom axis), respectively. The measured resistances as a function of bending angle were almost invariant, even at 140°. For the bending fatigue tests, 300 bend–relax cycles were conducted, and the resistance was measured in both flat and bent (100°) positions after each cycle. It can be seen that there was very little change in resistance, which is clearly indicative of the excellent durability of the PEDOT/textile conductor. Upon release after the initial bending, the resistance increased by only 0.00012 %, which might be explained by complex changes in the geometry between the cracking and delamination of PEDOT/yarns in the PEDOT/textile. However, the PEDOT/textile conductor displayed rather stable resistance values after two or three bend–relax cycles, as shown in Figure 4d (top axis). Based on the above characterization, we demonstrate that PEDOT/textiles can be produced for possible electronic-textile heaters, where Joule heating is used to convert


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electricity to heat. This is very important for classic heat-based physiotherapy used in orthopedics to alleviate pain and reduce joint stiffness (e.g., related to vascular systems and their surrounding collagen tissues).52,53 We applied a voltage to the PEDOT/textile heater using a DC power supply and monitored the electrical current flowing through the heater. Figure 5 shows the temperature history of the PEDOT/textile heater as a function of time. The temperature response of PEDOT/textile at five different applied voltages is plotted in Figure 5a. When a bias of 7 V was applied to an 8 cm (distance between electrodes) × 7.8 cm (width) area of the PEDOT/textile, a temperature of ∼83.9 °C was obtained, showing its functionality at low voltages. For practical applications, the fast thermal response of a heater is an important parameter. In the current study, the steadystate temperature of the PEDOT/textile over a large area was reached within ∼70 s due to the good electrical and thermal conductivity of the material. Thus, to sum up, our PEDOT/textile heater was confirmed to have a fast response time as an electronic-textile heater, in spite of the fact that the PEDOT/textile contained many macro/microporous structures (inset photograph of Figure 5b). Figure 5b indicates a linear relationship between the steady-state temperature and the power consumption of the PEDOT/textile heater. The power density was calculated by P/area = (I2 × R)/area, where P is the power, I is the current through the resistor, and R is the resistance. As a result, a low power density of only 1.34 W·cm-2 was observed upon reaching a temperature of ∼83.9 °C, which is comparable to or even lower than that of various other heaters for carbon (carbon nanotube or graphene)-, metal nanowire-, or transition metal oxide-based films or wearable heaters.52,54-56 Moreover, the PEDOT/textile’s dynamic thermal response was examined using repetitive on-off cycles with a square-wave voltage (0-4 V) to verify the


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PEDOT/textile’s stable and fast heating/cooling properties. The heating and cooling times in each cycle were 280 and 120 s, respectively. The temperature profiles remained almost identical for 100 on-off cycles, indicating that the PEDOT/textile has very stable Joule heating properties (Figure 5c). PEDOT/textile Joule heating under steady-state conditions was visualized via infrared (IR) imaging and with photographs taken under various bending and twisting conditions (Figure 5d). The thermal images show nearly uniform heat generation by the PEDOT/textile heater. The low temperature at the PEDOT/textile heater’s edges in the IR image is due to extra heat loss at the edges.31,57,58

The histogram corresponding to heat

generation by the PEDOT/textile heater (active area: ∼3 × 3 cm2; applied voltage of 0 to 6 V using an interval time of ∼1 min) is shown in Movie M1 and Figure S6 in the Supporting Information. The resistive heating of PEDOT/textile at 6 V typically lasted between 23 and 28 s, at which point the PEDOT/textile would start smoking while the breakdown current was not reached. The temperature at this time was about 160 °C. These results reveal possible loss of remaining traces of solvent and dopant around 160 °C; thus, the PEDOT/textile is stable up to a temperature of ∼159 °C. It is noteworthy that the PEDOT/textile heater is more scalable, cost-effective, and roll-to-roll processable than carbon nanotubes, graphene, or silver nanowire film heaters on comparable plastic substrates.52,54-56 These results indicate that the PEDOT/textile is potentially applicable to thermal therapy for decreasing pain in joints and muscles.52,53 We also fabricated an all-solid-state supercapacitor with a H2SO4-PVA gel electrolyte, and studied its electrochemical behavior, of which results are shown in Figure 6. The active area of the fabricated all-solid-state supercapacitor was 1.5 × 3 cm2 (thickness ∼306.5 µm). Because of its good conductivity and 3D structure, the PEDOT-


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NA/PEDOT/textile served as the active material and the current collector, as shown in the inset in Figure 6a. Figure 6a shows the cyclic voltammetry (CV) curves of the PEDOTNA/PEDOT/textile electrode at different scan rates. At slow scan rates, the CV curves of the

PEDOT-NA/PEDOT/textile

device

exhibited

a

quasi-rectangular

profile,

demonstrating the superior pseudocapacitive performance of the π-conducting polymer as it underwent oxidation and reduction reactions and thus stored and released SO3- anions. To further evaluate the performance of the PEDOT-NA/PEDOT/textile electrode, charge– discharge (CD) measurements were performed at current densities of 0.4, 0.8, 2, and 4 mA·cm-2 between 0 and 1.2 V, and the corresponding CD curves are shown in Figure 6b. The CD curves of the PEDOT-NA/PEDOT/textile are almost isosceles triangles, with a small drop in internal resistance (IR), which indicates good Coulombic efficiency (η = ∆td/∆tc, where ∆td is the discharge time and ∆tc is the charge time) of the PEDOTNA/PEDOT/textile. The Coulombic efficiency as a function of current density is shown in blue in Figure 6c. The η value of the PEDOT-NA/PEDOT/textile is above 98 % at all current densities, which ensures efficient mass transport and low internal resistance. This observation was further confirmed by electrochemical impedance spectroscopy (EIS) measurements. Figure 6c shows the Nyquist plot in red for the symmetric supercapacitor recorded from 0.01 Hz to 1 MHz with an AC perturbation amplitude of 10 mV. In the high-frequency region, the Nyquist plot exhibits an arc shape, while in the low-frequency region, it exhibits a straight line. The latter demonstrates the superior capacitive behavior caused by fast ion diffusion in the 3D PEDOT-NA/PEDOT/textile electrode. The equivalent series resistance of the PEDOT/textile was 5.8 Ω. These low ESR values may be due to the high conductivity of the PEDOT-NA/PEDOT/textile. The areal capacitances


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(volumetric capacitance) of the PEDOT-NA/PEDOT/textile supercapacitor device estimated from the discharging curves were 563.3, 471.3, 321.7, and 262.7 mF·cm-2 (405.8, 341.2, 231.8 and 190 mF·cm-3) at current densities of 0.4, 0.8, 2, and 8 mA·cm-2, respectively, as shown in Figure 6d. Electrochemical cycling stability tests were performed at a current density of 2 mA·cm-2 from 0 to 1.2 V. The PEDOT-NA/PEDOT/textile supercapacitor device showed capacitance retention of 90.9 and 81.4 % of its initial performance after 5000 and 10,000 cycles, respectively, which clearly signifies the excellent electrochemical stability of PEDOT-NA/PEDOT/textile electrodes (Figure 7a). The capacitance decay occurs due to the PEDOT chains’ repetitive swelling and shrinkage.59 The volumetric energy (E) and power (P) densities are important parameters used to illustrate the electrochemical performance of supercapacitors. We have therefore tabulated a Ragone plot in Figure 7b that compares the volumetric energy and power densities of the PEDOT-NA/PEDOT/textile reported in this work to the values reported for other quasi- and/or all-solid-state supercapacitors. Obviously, both the volumetric energy and power densities were significantly enhanced due to the wide operating voltage (0–1.2 V). At a power density of 1.75 W·cm-3, the energy density of the PEDOT/textile symmetric supercapacitor reached 0.038 Wh·cm-3, and it retained an energy density of 0.0812 Wh·cm-3 at a power density of 0.174 W·cm-3. These power and energy densities are considerably higher than those recently reported for π-conducting polymers,29,60-62 conducting polymers coated on nanostructured transition metal oxides,63 conducting polymer-coated carbon nanotubes on Pt wire,5 MnO2–carbon nanotube composites,64 and


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even carbon-based supercapacitors such as reduced graphene oxide,65 reduced graphene oxide–carbon nanotube composites,66 and carbon nanotubes on carbon fiber.67 Electrochemical stability against mechanical deformation (Figure 8a) is an important factor for evaluating the performance of flexible supercapacitors. Figure 8b shows the CV characteristics when the PEDOT-NA/PEDOT/textile supercapacitor was forced to bend at different angles. The quasi-rectangular shapes of the CV curves in Figure 8b remained identical, regardless of exposure to rolling, twisting, or various degrees of bending. The capacitance was only slightly decreased through normal, severely bent, rolled, and twisted conditions, indicating excellent durability. To assess the impact of repeated bending on the quality of the symmetric PEDOT-NA/PEDOT/textile supercapacitor, we chose an angle of ∼60° at a scan rate of 100 mV·s-1 and subjected the supercapacitor to a total of 300 bending cycles. Notably, only moderately degraded CV curves after 300 bending cycles can be observed in Figure 8c, indicating that all-solid-state symmetric PEDOTNA/PEDOT/textile supercapacitor maintained good performance and was insensitive to repeated bending. This excellent performance is due to the flexibility characteristics of both PEDOT and the textile.

CONCLUSION A new 3D conducting polymer-based nanostructure was successfully fabricated on a commercial 3D cotton textile by solution and vapor-phase polymerization of PEDOT. The sheet resistance of the PEDOT/textile via a simple drop-casting polymerization method was uniformly distributed between 4.6 and 4.9 Ω·sq-1 on 10 × 10 cm2 with high mechanical/electrical stability for smart


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textronics. We demonstrated flexible Joule heating of the PEDOT/textile, with efficient heating using less energy and at lower voltages compared to other materials. A flexible heater with a large area (8 × 7.8 cm2) reached a saturated temperature of ∼83.9 °C when a bias of 7 V was applied for ∼70 s as a result of the good electrical and thermal conductivity of PEDOT. We also synthesized nanostructured PEDOT arrays on the PEDOT/textile via vapor-phase polymerization for the fabrication of textile-based energy storage devices. The resulting PEDOT-NA arrays on PEDOT/textile were used to fabricate all-solid-state symmetric supercapacitors, which showed excellent mechanical durability and flexibility. The PEDOT-NA/PEDOT/textile supercapacitors had the following advantages: high capacitance, power density, energy density, mechanical durability, flexibility, and scalability. This led them to outperform other conducting polymer composites/hybrids reported in the existing literature. It showed outstanding performance, with an areal capacitance of 563.3 mF·cm-2 at 0.4 mA·cm-2. Furthermore, the maximum volumetric power density and energy density were 1.75 W·cm-3 and 0.0812 Wh·cm-3, respectively. All results taken together, this work paves the way for further nanomaterial synthesis on textiles, and provides very promising results for the scalable production of wearable smart textronics and energy storage and conversion systems.

EXPERIMENTAL SECTION Materials The monomer 3,4-ethylenedioxythiophene was procured from Alfa Aesar Corp. IPA, Iron(III) perchlorate, PVA (average Mw ≈ 130,000; 99 % hydrolyzed), and concentrated sulfuric acid (99.999 %) were procured from Aldrich Corp. All of the reagents were used


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without further purification. Commercial cotton fabric was obtained from a local household items store and cleaned with ethanol and deionized water followed by drying before use in the experiments.

Preparation of PEDOT/textile To prepare the highly conductive PEDOT/textile, 1.86 mM of Fe(ClO4)3 in IPA was dropped directly onto the cleaned and dried textile (area ∼11 × 11 cm2). The Fe(ClO4)3coated textile was then dried at room temperature. A solution of EDOT (0.46 mM) in IPA was dropped directly onto the Fe(ClO4)3-coated textile and allowed to dry and polymerize at room temperature for ∼2 h. The PEDOT-coated textile was washed repeatedly with warm IPA (∼40 °C) and deionized water, followed by drying at room temperature for 12 h. This procedure [Fe(ClO4)3 coating and EDOT polymerization] was repeated four more times.

Preparation of PEDOT nano-ascidian (PEDOT-NA) arrays on PEDOT/textile The PEDOT/textile was immersed in a saturated FeCl3–IPA solution. After drying at room temperature, the subsequent vapor-deposition polymerization of EDOT (0.1 mL) monomer was carried out in a pressure-controllable reactor at 70 °C for 4 h at a pressure of ∼0.1 Torr. The PEDOT-coated textile was washed repeatedly with warm IPA (∼40 °C) and deionized water, which was followed by drying at room temperature for 12 h.

General characterization


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FTIR measurements were carried out using an Agilent Cary 670 FTIR spectrometer. Raman spectra were recorded on a LabRam Aramis Raman spectrometer from Horiba Jobin Yvon with a laser wavelength of 532 nm. XRD analysis was performed using an Xray diffractometer (SMARTLAB, Rigaku) with Cu Kα (λ = 1.54 Å) radiation. All XPS measurements were performed with a Sigma Probe system (ThermVG) using a monochromatic Al Kα X-ray source. Field emission SEM (JSM-6701F/INCA Energy, JEOL) was employed to observe the microstructure. A four-probe method using R-CHEK (model RC2175) or a fully automatic four-probe system (CMT-SR1000N, Advanced Instrument Technology) and a Keithley 2602A source meter, respectively, was employed to establish the sheet resistance and electrical properties. All thermal properties and images were obtained using an infrared (IR) camera (T620 FLIR) and in combination with analysis software (FLIR tools).

Fabrication of PEDOT/textile heater A single piece of the PEDOT/textile with an active area of ∼8 × 7.8 cm2 was wired to both ends of a copper wire.

Fabrication of the flexible all-solid-state symmetric supercapacitor To produce the H2SO4-PVA gel electrolyte, PVA powder (3 g), H2SO4 (3 g), and deionized water (30 mL) were mixed. The mixture was then heated to approximately 85°C under magnetic stirring until it became clear. Subsequently, the PEDOTNA/PEDOT/textile (active area ∼1.5 × 3 cm2) and a nylon membrane separator were immersed in the H2SO4-PVA gel for 2 h. Following air drying at room temperature for


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∼12 h, two pieces of the PEDOT-NA/PEDOT/textile were sandwiched together to form the device and then sealed carefully using polydimethylsiloxane elastomer and a crosslinker (Sylgard 184, Dow Corning) as a packaging substance. The active area was determined to be the geometric area of the PEDOT-NA/PEDOT/textile. All data were normalized by this geometric area and/or volume.

Electrochemical characterization The electrochemical characterization was carried out using a Versastat 3 potentiostat/galvanostat (Princeton Instrument) at room temperature. The comprehensive electrochemical properties of the as-obtained PEDOT/textile and assembled flexible supercapacitors were investigated by two-electrode electrochemical systems. EIS was employed in the frequency range of 0.01 Hz to 100 kHz using an AC amplitude of 10 mV and an open-circuit potential. The areal (Careal) or volumetric (Cvol) capacitance of the PEDOT/textile was calculated from the charge–discharge curves using the following equation: Careal (or Cvol) = (I·∆t)/[∆V·A(or Vol.)]

(1)

where Careal (or Cvol) is expressed in mF·cm-2 (or mF·cm-3), I is the constant current, ∆t is the discharge time, ∆V is the potential change after the IR drop, and A is the area (or Vol. the volume) of the PEDOT/textile device (device area: 4.5 cm2, total measured thickness: ∼306.5 µm). The volumetric energy (Evol) and power (Pvol) densities for the whole device were calculated from the capacitance value obtained using the charge–discharge method, according to the following equations:


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Evol (Wh·cm-3) = (Cvol·∆V2)/7.2

(2)

Pvol (W·cm-3) = (3600·Evol)/∆t

(3)

ASSOCIATED CONTENT Supporting Information The supporting Information is available free of charge on the ACS Publications website at DOI:xxxxxxxx. SEM images of the bare cotton textile; the morphology of PEDOT-NA on the PEDOT; Raman spectra of PEDOT and PEDOT-NA; XPS spectra of O 1s and Cl 2p; XRD spectrum of PEDOT/textile; temperature history of PEDOT/textile heater.

AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected] *E-mail: [email protected] Author Contributions


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I.K.M. S.W.K., and J. O. had the original ideas. I.K.M and J.O. contributed to the paper writing. I.K.M. carried out most of the experimental works. S.Y. and H.U.L. assisted some experiments and data analysis. Notes The authors declare no competing financial interest.

ACKNOWLEDGMENT This work was supported by the Future Semiconductor Device Technology Development Program (10044735) funded by MOTIE (Ministry of Trade, Industry & Energy) and KSRC (Korea Semiconductor Research Consortium). It was also supported by the MSIP (Ministry of Science, ICT and Future Planning), Korea, under the “ICT Consilience Creative Program” (IITPR0346-16-1008) supervised by the IITP (Institute for Information & Communication Technology Promotion) and by the National Research Foundation (NRF) of Korea (Future Planning of Korea, MSIP No. 2014R1A2A2A01007321) and Ministry of Trade, Industry & Energy of Korea (The Industrial Strategic Technology Development Program, 10051513).

REFERENCES (1) Jost, K.; Gion, G.; Gogotsi, Y. Textile Energy Storage in Perspective. J. Mater. Chem. A 2014, 2, 10776-10787. (2) Hsu, P.-C.; Liu, X.; Liu, C.; Xie. X.; Lee, H. R.; Welch, A. J.; Zhao, T.; Cui, Y. Personal Thermal Management by Metallic Nanowire-Coated Textile. Nano Lett. 2015, 15, 365-371.


22-42

Page 23 of 42

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(3) Pang, C.; Lee, G.-Y.; Kim, T.-I.; Kim, S. M.; Kim, H. N.; Ahn, S.-H.; Suh, K.-Y. A Flexible and Highly Sensitive Strain-Gauge Sensor using Reversible Interlocking of Nanofibres. Nat. Mater. 2012, 11, 795-801. (4) Hu, L.; Pasta, M.; Mantia, F. L.; Cui, L.; Jeong, S.; Deshazer, H. D.; Choi, J. W.; Han, S. M.; Cui, Y. Stretchable, Porous, and Conductive Energy Textiles. Nano Lett. 2010, 10, 708714. (5) Zhang, D.; Miao, M.; Niu, H.; Wei, Z. Core-Spun Carbon Nanotube Yarn supercapacitors for Wearable Electronic Textiles. ACS Nano 2014, 8, 4571-4579. (6) Arbab, A. A.; Sun, K. C.; Sahito, I. A.; Memon, A. A.; Choi, Y. S.; Jeong, S. H. Fabrication of Textile Fabric Counter Electrodes using Activated Charcoal Doped Multi Walled Carbon Nanotube Hybrids for Dye Sensitized Solar Cells. J. Mater. Chem. A 2016, 4, 1495-1505. (7) Hu, L.; Mantia, F. L.; Wu, H.; Xie, X.; McDonough, J.; Pasta, M.; Cui, Y. Lithium-Ion Textile Batteries with Large Areal Mass Loading. Adv. Energy Mater. 2011, 1, 1012-1017. (8) Ilanchezhiyan, P.; Zakirov, A. S.; Yuldashev, S. U.; Cho, H. D.; Kang, T. W.; Mamadalimov, A. T. Highly Efficient CNT Functionalized Cotton Fabrics for Flexible/Wearable Heating Applications. RSC Adv. 2015, 5, 10697-10702. (9) Pasta, M.; Mantia, F. L.; Hu, L.; Deshazer, H. D.; Cui, Y. Aqueous Supercapacitors on Conductive Cotton. Nano Res. 2010, 3, 452-458. (10) Weng, Z.; Su, Y.; Wang, D.-W.; Li, F.; Du, J.; Cheng, H.-M. Graphene-Cellulose Paper Flexible Supercapacitors. Adv. Energy Mater. 2011, 1, 917-922.


23-42


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 42

(11) Gao, Z.; Bumgardner, C.; Song, N.; Zhang, Y.; Li, J.; Li, X. Cotton-Textile-Enabled Flexible Self-Sustaining Power Packs via Roll-to-Roll Fabrication. Nat. Commun. 2016, 7, 11586. (12) Liu, L.; Yu, Y.; Yan, C.; Li, K.; Zheng, Z. Wearable Energy-Dense and Power-Dense Supercapacitor Yarns Enabled by Scalable Graphene-Metallic Textile Composite Electrodes. Nat. Commun. 2015, 6, 7260. (13) Li, Z.; Xu, Z.; Liu, Y.; Wang, R.; Gao, C. Multifunctional Non-Woven Fabrics of Interfused Graphene Fibres. Nat. Commun. 2016, 7, 13684. (14) Zhao, C.; Shu, K.; Wang, C.; Gambhir, S.; Wallace, G. G. Reduced Graphene Oxide and Polypyrrole/Reduced Graphene Oxide Composite Coated Stretchable Fabric Electrodes for Supercapacitor Application. Electrochimica Acta 2015, 172, 12-19. (15) Wang, Z.; Zheng, Z.; Zheng, S.; Chen, S.; Zhao, F. Carbonized Textile with FreeStanding Threads as an Efficient Anode Material for Bioelectrochemical Systems. J. Power Sources 2015, 287, 269-275. (16) Zhang, M.; Wang, C.; Wang, H.; Jian, M.; Hao, X.; Zhang, Y. Carbonized Cotton Fabric for High-Performance Wearable Strain Sensors. Adv. Funct. Mater. 2017, 27, 1604795. (17) Song, K.; Song, W.-L.; Fan, L.-Z. Scalable Fabrication of Exceptional 3D Carbon Networks for Supercapacitors. J. Mater. Chem. A 2015, 3, 16104-16111. (18) Fan, L.-Z.; Chen, T.-T.; Song, W.-L.; Li, X.; Zhang, S. High Nitrogen-Containing Cotton derived 3D Porous Carbon Frameworks for High-Performance Supercapacitors. Sci. Rep. 2015, 5, 15388.


24-42

Page 25 of 42

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(19) Lee, Y.-H.; Kim, Y.; Lee, T.-I.; Lee, I.; Shin, J.; Lee, H. S.; Kim, T.-S.; Choi, J. W. Anomalous Stretchable Conductivity using an Engineered Tricot Weave. ACS Nano 2015, 9, 12214-12223. (20) Liu, S.; Hu, M.; Yang, J. A Facile Way of Fabricating a Flexible and Conductive Cotton Fabric. J. Mater. Chem. C 2016, 4, 1320-1325. (21) Lee, J.; Kwon, H.; Seo, J.; Shin, S.; Koo, J. H.; Pang, C.; Son, S.; Kim, J. H.; Jang, Y. H.; Kim, D. E.; Lee, T. Conductive Fiber-Based Ultrasensitive Textile Pressure Sensor for Wearable Electronics. Adv. Mater. 2015, 27, 2433-2439. (22) Lee, H. M.; Choi, S.-Y.; Jung, A.; Ko, S. H. Highly Conductive Aluminum Textile and Paper for Flexible and Wearable Electronics. Angew. Chem. Int. Ed. 2013, 52, 7718-7723. (23) Lee, S.; Shin, S.; Lee, S.; Seo, J.; Lee, J.; Son, S.; Cho, H. J.; Algadi, H.; Al-Sayari, S. ; Kim, D. E.; Lee, T. Ag Nanowire Reinforced Highly Stretchable Conductive Fibers for wearable electronics. Adv. Funct. Mater. 2015, 25, 3114-3121. (24) Little, B. K.; Li, Y.; Cammarata, V.; Broughton, R.; Mills, G. Metallization of Kevlar Fibers with Gold. ACS Appl. Mater. Interfaces 2011, 3, 1965-1973. (25) Zhu, S.; So, J.-H.; Mays, R.; Desai, S.; Barnes, W. R.; Pourdeyhimi, B.; Dickey, M. D. Ultrastretchable Fibers with Metallic Conductivity using a Liquid Metal Alloy Core. Adv. Funct. Mater. 2013, 23, 2308-2314. (26) Hamdani, S. T. A.; Potluri, P.; Fernando, A. Thermo-mechanical Behavior of Textile Heating Fabric Based on Silver Coated Polymeric Yarn. Materials 2013, 6, 1072-1089. (27) Zhou, J.; Mulle, M.; Zhang, Y.; Xu, X.; Li, E. Q.; Han, F.; Thoroddsen, S. T.; Lubineau, G. High-Ampacity Conductive Polymer Microfibers as Fast Response Wearable Heaters and Electromechanical Actuators. J. Mater. Chem. C 2016, 4, 1238-1249.


25-42


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 26 of 42

(28) Santhiago, M.; Bettini, J.; Araújo, S. R.; Bufon, C. C. B. Three-Dimensional Organic Conductive Networks Embedded in Paper for Flexible and Foldable Devices, ACS Appl. Mater. Interfaces 2016, 8, 10661-10664. (29) Anothumarkkool, B.; Soni, R.; Bhange, S. N.; Kurungot, S. Novel Scalable Synthesis of Highly Conducting and Robust PEDOT Paper for a High Performance Flexible Solid Supercapacitor. Energy Environ. Sci. 2015, 8, 1339-1347. (30) Franklin, A. D. Chen, Z. Length Scaling of Carbon Nanotube Transistors. Nat. Nanotechnol. 2010, 5, 858-862. (31) Bae, J. J.; Lim, S. C.; Han, G. H.; Jo, Y. W.; Doung, D. L.; Kim, E. S.; Chae, S. J.; Huy, T. Q.; Luan, N. V.; Lee, Y. H. Heat Dissipation of Transparent Graphene Defoggers. Adv. Funct. Mater. 2012, 22, 4819-4826. (32) Yoon. Y.-H; Song, J.-W.; Kim, D.; Kim, J.; Park, J.-K.; Oh, S.-K.; Han, C.-S. Transparent Film Heater using Single-Walled Carbon Nanotubes. Adv. Mater. 2007, 19, 4284-4287. (33) Kim, N.; Lee, B. H.; Choi, D.; Kim, G.; Kim, H.; Kim, J.-R.; Lee, J.; Kahng, Y. H.; Lee, K. Role of Interchain Coupling in the Metallic State of Conducting Polymers. Phys. Rev. Lett. 2012, 109, 106405. (34) van de Ruit, K.; Cohen, R. I.; Bollen, D.; van Mol, T.; Yerushalmi-Rozen, R.; Janssen, R. A. J.; Kemerink, M. Quasi-One Dimensional In-Plane Conductivity in Filamentary Films of PEDOT:PSS. Adv. Funct. Mater. 2013, 23, 5778-5786. (35) Hofmann, A. I.; Dmaal, W. T. T.; Mumtaz, M.; Katsigiannopoulos, D.; Brochon, C.; Schütze, F.; Hild, O. R.; Cloutet, E.; Hadiioannou, G. An Alternative Anionic


26-42

Page 27 of 42

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Polyelectrolyte for Aqueous PEDOT Dispersions: Toward Printable Transparent Electrodes. Angew. Chem. Int. Ed. 2015, 54, 8506-8510. (36) Wei, Q.; Mukaida, M.; Naitoh, Y.; Ishida, T. Morphological Change and Mobility Enhancement in PEDOT:PSS by Adding Co-Solvents. Adv. Mater. 2013, 25, 2831-2836. (37) Li, J.; Qiao, X.; Xiong, Y.; Li, H.; Zhu, D. Five-Ring Fused Tetracyanothienoquinoids as High-Performance and Solution-Processable n-Channel Organic Semiconductors: Effect of the Branching Position of Alkyl Chains. Chem. Mater. 2014, 26, 5782-5788. (38) Hamedi, M. M.; Ainla, A.; Güder, F.; Christodouleas, D. C.; Fernández-Abedul, M. T.; Whitesides, G. M. Integrating Electronics and Microfludics on Paper. Adv. Mater., 2016, 28, 5054-5063. (39) Heywang, G.; Jonas, F. Poly(alkylenedioxythiophene)s-New, Very Stable Conducting Polymers. Adv. Mater. 1992, 4, 116-118. (40) Shown, I.; Ganguly, A.; Chen, L.-C.; Chen, K.-H. Conducting Polymer-Based Flexible Supercapacitor. Energy Sci. and Eng. 2015, 3, 2-26. (41) Bao, L.; Li, X. Towards Textile Energy Storage from Cotton T-shirts. Adv. Mater. 2012, 24, 3246-3252. (42) Yoon, J.; Jeong, Y.; Kim, H.; Yoo, S.; Jung, H. S.; Kim, Y.; Hwang, Y.; Hyun, Y.; Hong, W.-K.; Lee, B. H.; Choa, S.-H.; Ko, H. C. Robust and Stretchable Indium Gallium Zinc Oxide-Based Electronic Textiles Formed by Cilia-Assisted Transfer Printing. Nat. Commun. 2016, 7, 11477. (43) Cho, G.; Han, A. Review of Performance Evaluation on e-Textiles and Textile-Based Keypads. International Journal of Fashion Design, Technology and Education, 2011, 4, 8389.


27-42


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 28 of 42

(44) Weng, W.; Chen, P.; He, S.; Sun, X.; Peng, H. Smart Electronic Textiles. Angew. Chem. Int. Ed. 2016, 55, 6140-6169. (45) Rossi, D. D. Electronic Textiles: a Logical Step. Nat. Mater. 2007, 6, 328-329. (46) Yamada, T.; Hayamizu, Y.; Yamamoto, Y.; Yomogida, Y.; Izadi-Najafabadi, A.; Futaba, D. N.; Hata, K. A Stretchable Carbon Nanotube Strain Sensor for Human-Motion Detection. Nat. Nanotechnol. 2011, 6, 296-301. (47) D’Arcy, J. M.; El-Kady, M. F.; Khine, P. P.; Zhang, L.; Lee, S. H.; Davis, N. R.; Liu, D. S.; Yeung, M. T.; Kim, S. Y.; Turner, C. L.; Lech, A. T.; Hammond, P. T.; Kaner, R. B. Vapor-Phase

Polymerization

of

Nanofibrillar

Poly(3,4-ethylenedioxythiophene)

for

Supercapacitors. ACS Nano 2014, 8, 1500-1510. (48) Chelawat, H.; Vaddiraju, S.; Gleason, K. Conformal, Conducting Poly(3,4ethyleneddioxythiophene) Thin Films Deposited using Bromine as the Oxidant in a Completely Dry Oxidative Chemical Vapor Deposition Process. Chem. Mater. 2010, 22, 2864-2868. (49) Nevrela, J.; Micjan, M.; Novota, M.; Kovacova, S.; Pavuk, M.; Juhasz, P.; Kovac, J.; Jakabovic, J.; Weis, M. Secondary Doping in Poly(3,4-ethylenedioxythiophene):poly(4styrenesulfonate) Thin Films. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1139-1146. (50) Park, H.; Lee, S. J.; Kim, S.; Ryu, H. W.; Lee, S. H.; Choi, H. H.; Cheng, I. W.; Kim, J.-H. Conducting Polymer Nanofiber Mats via Combination of Electrospinning and Oxidative Polymerization. Polymer 2013, 54, 4155-4160. (51) Anothumakkool, B.; Bhange, S. N.; Unni, S. M.; Kurungot, S. 1-Dimensional Confinement of Porous Polyethylenedioxythiophene using Carbon Nanofibers as a Solid


28-42

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Template; an Efficient Charge Storage Material with Improved Capacitance Retention and Cycle Stability. RSC Adv. 2013, 3, 11877-11887. (52) Choi, S.; Park, J.; Hyun, W.; Kim, J.; Kim, J.; Lee, Y. B.; Song, C.; Hwang, H. J.; Kim, J. H.; Hyeon, T.; Kim, D.-H. Stretchable Heater using Ligand-Exchanged Silver Nanowire Nanocomposite for Wearable Articular Thermotherapy. ACS Nano 2015, 9, 6626-6633. (53) Lehmann, J. F. Therapeutic Heat and Cold, 4th ed.; Williams & Wilkins: Baltimore, MD, 1990. (54) Kang, J.; Kim, H.; Kim, K. S.; Lee, S.-K.; Bae, S.; Ahn, J.-H.; Kim, Y.-J.; Choi, J.B.; Hong, B. H. High-Performance Graphene-Based Transparent Flexible Heaters. Nano Lett. 2011, 11, 5154-5158. (55) Kim, D.; Zhu, L.; Jeong, D.-J.; Chun, K.; Bang, Y.-Y.; Kim, S.-R.; Kim, J.-H.; Oh, S.-K. Transparent Flexible Heater Based on Hybrid of Carbon Nanotubes and Silver Nanowires. Carbon 2013, 63, 530-536. (56) Kim, H.-J.; Kim, Y.; Jeong, J.-H.; Choi, J.-H.; Lee, J.; Choi, D.-G. A CupronickelBased Micromesh Film for Use as a High-Performance and Low-Voltage Transparent Heater. J. Mater. Chem. A 2015, 3, 16621-16626. (57) Kang, J.; Jang, Y.; Kim, Y.; Cho, S.-H.; Suhr, J.; Hong, B. H.; Choi, J.-B.; Byun, D. An Ag-Grid/Graphene Hybrid Structure for Larger-scale, Transparent, Flexible Heaters. Nanoscale 2015, 7, 6567-6573. (58) Hong, S.; Lee, H.Lee, J.; Kwon, J.; Han S.; Suh, Y. D.; Cho, H.; Shin, J.; Yeo, J.; Ko, S. H. Highly Stretchable and Transparent Metal Nanowire Heater for Wearable Electronics Applications. Adv. Mater., 2015, 27, 4744-4751.


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(59) Wang, J.-G.; Yang, Y.; Huang, Z.-H.; Kang, F. MnO2/Polypyrrole Nanotubular Composites: Reactive Template Synthesis, Characterization and Application as Superior Electrode Materials for High-Performance Supercapacitors. Electrochem. Acta. 2014, 130. 642-649. (60) Yuan, L.; Xiao, X.; Ding, T.; Zhong, J.; Zhang, X.; Shen, Y.; Hu, B.; Huang, Y.; Zhou, J.; Wang, Z. L. Paper-Based Supercapacitors for Self-Powered Nanosystems. Angew. Chem. Int. Ed. 2012, 51, 4934-4938. (61) Meng, F.; Ding, Y. Sub-Micrometer-Thick All-Solid-State Supercapacitors with High power and Energy Densities. Adv. Mater. 2011, 23, 4098-4102. (62) Yuan, L.; Yao, B.; Huo, K.; Chen, W.; Zhou, J. Polypyrrole-Coated Paper for Flexible Solid-State Energy Storage. Energy Environ. Sci. 2013, 6, 470-476. (63) Kurra, N.; Park, J.; Alshareef, H. N. A Conducting Polymer Nucleation Scheme for Efficient Solid-State Supercapacitors on Paper. J. Mater. Chem. 2014, 2, 17058-17065. (64) Xiao, X.; Ding, T.; Yuan, L.; Shen, Y.; Zhong, Q.; Zhang, X.; Cao, Y.; Zhai, T.; Gong, L.; Chen, J.; Tong, Y.; Zhou, J.; Wang, Z. L. WO3-x/MoO3-x Core/Shell Nanowires on Carbon Fabric as an Anode for All-Solid-State Asymmetric Supercapacitors. Adv. Energy. Mater. 2012, 2, 1328-1332. (65) Pech, D.; Brunet, M.; Durou, H.; Huang, P.; Mochalin, V.; Gototsi, Y.; Taberna, P.L.; Simon, P. Ultrahigh-Power Micrometer-Sized Supercapacitors Based on Onion-like Carbon. Nat. Nanotechnol. 2010, 5, 651-654. (66) Biswas, S.; Drzal, L. T. Multilayerd Nanoarchitecture of Graphene Nanosheets and Polypyrrole Nanowires for High Performance Supercapacitor Electrodes. Chem. Mater. 2010, 22, 5667-5671.


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(67) Du, L.; Yang, P.; Yu, X.; Liu, P.; Song, J.; Mai, W. Flexible supercapacitors based on carbon nanotube/MnO2 nanotube hybrid porous films for wearable electronic devices. J. Mater. Chem. 2014, 2, 17561-17567.


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Figures Figure 1. (a) Schematic illustration of the solution-processed PEDOT/textile conductor. (b–e) Low- and high-magnification SEM images of the PEDOT/textile from different orientations: (b–d) View from the top showing the PEDOT/textile and (e) a side view of the PEDOT/textile. (f–i) EDX element mapping images of the PEDOT/textile.

Figure 2. SEM and EDX images showing the surface morphology of the PEDOT-NA arrays on the PEDOT/textile. (a) Low-magnification normal-view SEM micrograph of PEDOTNA/PEDOT/textile. (b–c) Tilted-view of a PEDOT/textile grown with a PEDOT-NA array on the surface. (d) High-magnification SEM image of aligned PEDOT-NA arrays. (e) The EDS spectrum (inset: electronic image of PEDOT-NA arrays) and (f–h) EDX element mapping of C, O, and S, respectively, for PEDOT-NA arrays on the PEDOT/textile.

Figure

3.

Spectroscopic

characterization

of

PEDOT/textile

and

PEDOT-

NA/PEDOT/textile. (a) FTIR and (b) Raman spectra. High-resolution XPS spectra of (c) C 1s and (d) S 2p.

Figure 4. Electrical properties of the PEDOT/textile. (a) Sheet resistance of the PEDOT/textile for different numbers of PEDOT polymerization layers. (b) Contour map of sheet resistance distribution over a large area of the PEDOT/textile (10 cm2). (c) I–V characteristics of PEDOT/textile under different deformation states. (d) Plot of relative resistance changes versus different bending angles (bottom axis) and bending cycles at a bending angle of 100° (top axis) for the PEDOT/textile.


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Figure 5. Electrical heating characteristics of the flexible PEDOT/textile heater (active area 8 × 7.8 cm2). (a) Temperature profile of the PEDOT/textile heater for different applied DC voltages. (b) Temperature as a function of power density for the PEDOT/textile. (c) Thermal stability of PEDOT/textile heater under switching cycles at an applied voltage 0 to 4 V. (d) IR images and photographs (insets) of the heater at 6 V under bending and twisting conditions.

Figure 6. Electrochemical performance of the all-solid-state symmetric supercapacitor with PEDOT-NA/PEDOT/textile. (a) Representative CVs at scan rates between 0 and 1.2 V. Inset is photograph of PEDOT-NA/PEDOT/textile supercapacitor device. (b) CD profiles at current densities between 0 and 1.2 V. (c) Nyquist plot of the PEDOTNA/PEDOT/textile electrode at an open-circuit potential (red circles) and Coulombic efficiency at different current densities (blue circles). (d) Areal and volumetric capacitance at different current densities.

Figure 7. (a) Cycling performance of the PEDOT-NA/PEDOT/textile for CD at a current density of 2 mA·cm-2. (b) Ragone plots of the PEDOT-NA/PEDOT/textile and some other devices from previous reports for comparison.

Figure 8. Electrochemical stability tests of the all-solid-state PEDOT-NA/PEDOT/textile supercapacitor. (a) Photographs of the all-solid-state PEDOT-NA/PEDOT/textile supercapacitor under different deformation states. (b) The CV curve of the PEDOTNA/PEDOT/textile at 10 mV·s-1 under bending, twisting, and rolling states. (c) Bending cycling test of the PEDOT-NA/PEDOT/textile supercapacitor before and after bending cycles up to ∼60° at a scan rate of 100 mV·s-1.


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Figure 1. (a) Schematic illustration of the solution-processed PEDOT/textile conductor. (b–e) Low- and high-magnification SEM images of the PEDOT/textile from different orientations: (b– d) View from the top showing the PEDOT/textile and (e) a side view of the PEDOT/textile. (f–i) EDX element mapping images of the PEDOT/textile.


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Figure 2. SEM and EDX images showing the surface morphology of the PEDOT-NA arrays on the PEDOT/textile. (a) Low-magnification normal-view SEM micrograph of PEDOTNA/PEDOT/textile. (b–c) Tilted-view of a PEDOT/textile grown with a PEDOT-NA array on the surface. (d) High-magnification SEM image of aligned PEDOT-NA arrays. (e) The EDS spectrum (inset: electronic image of PEDOT-NA arrays) and (f–h) EDX element mapping of C, O, and S, respectively, for PEDOT-NA arrays on the PEDOT/textile.


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Figure 3. Spectroscopic characterization of PEDOT/textile and PEDOTNA/PEDOT/textile. (a) FTIR and (b) Raman spectra. High-resolution XPS spectra of (c) C 1s and (d) S 2p.


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Figure 4. Electrical properties of the PEDOT/textile. (a) Sheet resistance of the PEDOT/textile for different numbers of PEDOT polymerization layers. (b) Contour map of sheet resistance distribution over a large area of the PEDOT/textile (10 cm2). (c) I–V characteristics of PEDOT/textile under different deformation states. (d) Plot of relative resistance changes versus different bending angles (bottom axis) and bending cycles at a bending angle of 100° (top axis) for the PEDOT/textile.


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Figure 5. Electrical heating characteristics of the flexible PEDOT/textile heater (active area 8 × 7.8 cm2). (a) Temperature profile of the PEDOT/textile heater for different applied DC voltages. (b) Temperature as a function of power density for the PEDOT/textile. (c) Thermal stability of PEDOT/textile heater under switching cycles at an applied voltage 0 to 4 V. (d) IR images and photographs (insets) of the heater at 6 V under bending and twisting conditions.


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Figure 6. Electrochemical performance of the all-solid-state symmetric supercapacitor with PEDOT-NA/PEDOT/textile. (a) Representative CVs at scan rates between 0 and 1.2 V. Inset is photograph of PEDOT-NA/PEDOT/textile supercapacitor device. (b) CD profiles at current densities between 0 and 1.2 V. (c) Nyquist plot of the PEDOT-NA/PEDOT/textile electrode at an open-circuit potential (red circles) and Coulombic efficiency at different current densities (blue circles). (d) Areal and volumetric capacitance at different current densities.


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Figure 7. (a) Cycling performance of the PEDOT-NA/PEDOT/textile for CD at a current density of 2 mA·cm-2. (b) Ragone plots of the PEDOT-NA/PEDOT/textile and some other devices from previous reports for comparison.


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Figure 8. Electrochemical stability tests of the all-solid-state PEDOT-NA/PEDOT/textile supercapacitor. (a) Photographs of the all-solid-state PEDOT-NA/PEDOT/textile supercapacitor under different deformation states. (b) The CV curve of the PEDOTNA/PEDOT/textile at 10 mV·s-1 under bending, twisting, and rolling states. (c) Bending cycling test of the PEDOT-NA/PEDOT/textile supercapacitor before and after bending cycles up to ∼60° at a scan rate of 100 mV·s-1.


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Table of Contents Graphic


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Three-Dimensional Flexible All-Organic Conductors for Multifunctional

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