5 research outputs found

    Three-Dimensional Flexible All-Organic Conductors for Multifunctional Wearable Applications

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    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 a cotton textile (PEDOT/textile). PEDOT/textile shows a very low sheet resistance of 4.6–4.9 Ω·sq<sup>–1</sup>. 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 cm<sup>2</sup>) 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 were prepared via a simple vapor-phase polymerization of 3,4-ethylenedioxythiophene 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<sup>–2</sup> at 0.4 mA·cm<sup>–2</sup> and extraordinary mechanical flexibility. The maximum volumetric power density and energy density of the nanostructured PEDOT on the textile were 1.75 W·cm<sup>–3</sup> and 0.0812 Wh·cm<sup>–3</sup>, respectively. It is expected that the wearable nanostructured conducting polymers will have advantages when used as structures for smart textronics and energy conversion/storage

    Nickel-Catalyzed Cross-Coupling of Vinyl Dioxanones to Form Enantiomerically Enriched Cyclopropanes

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    Under the conditions of nickel(0) catalysis, enantio­merically enriched vinyl dioxanones engage boroxines or B<sub>2</sub>(pin)<sub>2</sub> in stereo­specific cross-coupling to form diverse tetrasubstituted cyclopropanes bearing all-carbon quaternary stereo­centers. The collective data corroborate a mechanism involving nickel(0)-mediated benzylic oxidative addition with inversion of stereo­chemistry followed by reversible olefin insertion to form a (cyclopropyl­carbinyl)­nickel complex, which upon reductive elimination releases the cyclopropane

    Three-Dimensional Flexible All-Organic Conductors for Multifunctional Wearable Applications

    No full text
    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 a cotton textile (PEDOT/textile). PEDOT/textile shows a very low sheet resistance of 4.6–4.9 Ω·sq<sup>–1</sup>. 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 cm<sup>2</sup>) 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 were prepared via a simple vapor-phase polymerization of 3,4-ethylenedioxythiophene 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<sup>–2</sup> at 0.4 mA·cm<sup>–2</sup> and extraordinary mechanical flexibility. The maximum volumetric power density and energy density of the nanostructured PEDOT on the textile were 1.75 W·cm<sup>–3</sup> and 0.0812 Wh·cm<sup>–3</sup>, respectively. It is expected that the wearable nanostructured conducting polymers will have advantages when used as structures for smart textronics and energy conversion/storage

    Amphiphilic π‑Allyliridium <i>C</i>,<i>O</i>‑Benzoates Enable Regio- and Enantioselective Amination of Branched Allylic Acetates Bearing Linear Alkyl Groups

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    The first examples of amphiphilic reactivity in the context of enantio­selective catalysis are described. Commercially available π-allyliridium <i>C</i>,<i>O</i>-benzoates, which are stable to air, water and SiO<sub>2</sub> chromatography, and are well-known to catalyze allyl acetate-mediated carbonyl allylation, are now shown to catalyze highly chemo-, regio- and enantio­selective substitutions of branched allylic acetates bearing linear alkyl groups with primary amines

    Highly Efficient Enzyme Immobilization and Stabilization within Meso-Structured Onion-Like Silica for Biodiesel Production

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    Meso-structured onion-like silica (Meso-Onion-S) was synthesized and used as a host of enzyme immobilization. Meso-Onion-S has a 200–300 nm sized primary meso-structured onion building unit, and each onion unit has highly curved mesopores of 10 nm diameter in a multishell structure. Nanoscale enzyme reactors (NERs) in Meso-Onion-S were prepared via a two-step process of enzyme adsorption and subsequent enzyme cross-linking, which effectively prevents the leaching of cross-linked enzyme aggregates from highly curved mesopores of Meso-Onion-S. As a result, NERs in Meso-Onion-S significantly improved the enzyme stability as well as the enzyme loading. For example, NER of lipase (NER-LP) was stable under rigorous shaking for 40 days, while the control sample of adsorbed LP (ADS-LP) with no enzyme cross-linking showed a rapid inactivation due to rigorous enzyme leaching under shaking. Stable NER-LP was successfully employed to produce biodiesels and fatty acid methyl esters, from the LP-catalyzed transesterification of soybean oil with methanol. Interestingly, the specific activity of NER-LP was 23 and 10 times higher than those of free LP and ADS-LP, respectively, revealing the importance of LP stabilization in the form of NER-LP in the presence of organic solvents
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