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    Enhanced Piezoelectric Performance of Poly(Vinylidene Fluoride) Nanocomposites with Synthesized Zinc Oxide Nanowires and Branched Carbon Nanotubes via Melt Mixing Process
    (Wiley-V C H Verlag Gmbh, 2025) Kaplan, Muesluem; Alp, Emre; Borazan, Ismail; Krause, Beate; Poetschke, Petra
    This study presents the development of high-performance poly(vinylidene fluoride) (PVDF) based piezoelectric nanocomposites incorporating branched carbon nanotubes (bCNTs) and zinc oxide nanowires (ZnO NWs) through a scalable melt mixing process. ZnONWs with uniform morphology (mean diameter: 36.5 nm) are successfully synthesized and characterized. FTIR analysis confirms that incorporating bCNTs into PVDF significantly enhances the beta-phase content, while adding ZnO NWs (1-10 wt.%) resulted in progressive intensification of beta-phase characteristic peaks, with higher ZnO content showing stronger electroactive phase formation. The optimized composition (PVDF/0.5 wt.% bCNTs/5 wt.% ZnO NWs) demonstrates superior piezoelectric performance with a power density of 5.62 mu W cm-2, voltage output of 1.55 V, and current output of 14.48 mu A. Moreover, the composite exhibits excellent mechanical properties with a tensile strength of 48 MPa and maintains stable performance under cyclic loading. The enhanced performance is attributed to the synergistic effect between bCNTs and ZnO NWs, optimal beta-phase formation, and efficient charge transfer pathways. This study demonstrates the potential of melt-mixed PVDF nanocomposites for practical energy harvesting applications.
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    Functional Properties of Electrospun Polymer Mats Coated With SWCNTs by a Simultaneous Electrospraying Process
    (John Wiley and Sons Inc, 2026) Krause, Beate; Staudinger, Ulrike; Lötsch, Julia; Fischer, Dieter; Göbel, Michael Wilhelm; Borazan, Ismail
    An one-step procedure of simultaneous electrospraying and electrospinning is employed to produce fiber mats of a poly(vinylidene fluoride) (PVDF)/thermoplastic polyurethane (TPU) blend and polylactide (PLA) coated with singlewalled carbon nanotubes (SWCNTs). Thermoelectric investigation of the mats yielded Seebeck coefficients of 21–27 µV·K?1 that are almost independent of the SWCNT content and the polymer type. Control measurements using SWCNT buckypapers reveals that the thermoelectric properties of the SWCNTs is mostly determined by n-type doping effect of the solvents and additives used for electrospraying; the polymer nanofibers act mostly as porous mechanical support. Gas sensing experiments using PVDF/TPU and PLA-based electrospun mats containing 0.25 wt% SWCNTs exposed to saturated acetone vapor demonstrate a significant sensor response (change in resistance) for both polymers. Sensor recovery is more effective in the PLA-based mats compared to the PVDF-based one. In cyclic tests with short exposure times, both mats show highly stable and reproducible sensing behavior. The sensing mechanism is primarily driven by interactions between the solvent molecules and the SWCNTs (charge transfer) rather than by interactions with the polymer matrix (e.g., polymer swelling). © 2026 The Author(s). Macromolecular Materials and Engineering published by Wiley-VCH GmbH.