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    A High-Voltage, Dendrite-Free, and Durable Zn–Graphite Battery
    (Weinheim : Wiley-VCH, 2019) Wang, Gang; Kohn, Benjamin; Scheler, Ulrich; Wang, Faxing; Oswald, Steffen; Löffler, Markus; Tan, Deming; Zhang, Panpan; Zhang, Jian; Feng, Xinliang
    The intrinsic advantages of metallic Zn, like high theoretical capacity (820 mAh g−1), high abundance, low toxicity, and high safety have driven the recent booming development of rechargeable Zn batteries. However, the lack of high-voltage electrolyte and cathode materials restricts the cell voltage mostly to below 2 V. Moreover, dendrite formation and the poor rechargeability of the Zn anode hinder the long-term operation of Zn batteries. Here a high-voltage and durable Zn–graphite battery, which is enabled by a LiPF6-containing hybrid electrolyte, is reported. The presence of LiPF6 efficiently suppresses the anodic oxidation of Zn electrolyte and leads to a super-wide electrochemical stability window of 4 V (vs Zn/Zn2+). Both dendrite-free Zn plating/stripping and reversible dual-anion intercalation into the graphite cathode are realized in the hybrid electrolyte. The resultant Zn–graphite battery performs stably at a high voltage of 2.8 V with a record midpoint discharge voltage of 2.2 V. After 2000 cycles at a high charge–discharge rate, high capacity retention of 97.5% is achieved with ≈100% Coulombic efficiency. © 2019 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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    A Printable Paste Based on a Stable n-Type Poly[Ni-tto] Semiconducting Polymer
    (Basel : MDPI, 2019) Tkachov, Roman; Stepien, Lukas; Greifzu, Moritz; Kiriy, Anton; Kiriy, Nataliya; Schüler, Tilman; Schmiel, Tino; López, Elena; Brückner, Frank; Leyens, Christoph
    Polynickeltetrathiooxalate (poly[Ni-tto]) is an n-type semiconducting polymer having outstanding thermoelectric characteristics and exhibiting high stability under ambient conditions. However, its insolubility limits its use in organic electronics. This work is devoted to the production of a printable paste based on a poly[Ni-tto]/PVDF composite by thoroughly grinding the powder in a ball mill. The resulting paste has high homogeneity and is characterized by rheological properties that are well suited to the printing process. High-precision dispenser printing allows one to apply both narrow lines and films of poly[Ni-tto]-composite with a high degree of smoothness. The resulting films have slightly better thermoelectric properties compared to the original polymer powder. A flexible, fully organic double-leg thermoelectric generator with six thermocouples was printed by dispense printing using the poly[Ni-tto]-composite paste as n-type material and a commercial PEDOT-PSS paste as p-type material. A temperature gradient of 100 K produces a power output of about 20 nW. © 2019 by the authors.
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    Direct Observation of Plasmon Band Formation and Delocalization in Quasi-Infinite Nanoparticle Chains
    (Washington, DC : ACS Publ., 2019) Mayer, Martin; Potapov, Pavel L.; Pohl, Darius; Steiner, Anja Maria; Schultz, Johannes; Rellinghaus, Bernd; Lubk, Axel; König, Tobias A.F.; Fery, Andreas
    Chains of metallic nanoparticles sustain strongly confined surface plasmons with relatively low dielectric losses. To exploit these properties in applications, such as waveguides, the fabrication of long chains of low disorder and a thorough understanding of the plasmon-mode properties, such as dispersion relations, are indispensable. Here, we use a wrinkled template for directed self-assembly to assemble chains of gold nanoparticles. With this up-scalable method, chain lengths from two particles (140 nm) to 20 particles (1500 nm) and beyond can be fabricated. Electron energy-loss spectroscopy supported by boundary element simulations, finite-difference time-domain, and a simplified dipole coupling model reveal the evolution of a band of plasmonic waveguide modes from degenerated single-particle modes in detail. In striking difference from plasmonic rod-like structures, the plasmon band is confined in excitation energy, which allows light manipulations below the diffraction limit. The non-degenerated surface plasmon modes show suppressed radiative losses for efficient energy propagation over a distance of 1500 nm. © 2019 American Chemical Society.
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    Metal Plastic Hybrids: Optimisation in model experiments [Metall-Kunststoff-Verbunde: Modellversuche zur Optimierung]
    (Weinheim : Wiley-VCH, 2019) Bräuer, M.; Edelmann, M.; Lehmann, D.; Tuschla, M.
    Metal plastic hybrids will become more important as components for lightweight constructions. It is reported about optimisation of making three layer hybrids consisted of a steel plate, an adhesion layer based of uretdione powder coating material and a flexible component polyurethane in model experiments. Hybrid formation is performed in a compression moulding process. The adhesion layer and the polyurethane are modified to increase the hybrid bond strength. Peel test are conducted to quantitatively characterize the bond strength and an apparent energy release rate is calculated based on the peel force. For hybrids with widths of 2 mm polyurethane stripes it is possible to increase the apparent energy release rate for about 30 % to 16 N/mm in comparison with a hybrid with unmodified components. These hybrids have the same high bond strength level as the strongest hybrids reported in literature. Concluding the optimisation results are discussed related to their relevancy for the interpretation of the adhesion mechanisms in the interface between adhesion layer and polyurethane. © 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.