Solid-state and flexible zinc carbon (or Leclanche) batteries are fabricated using a combination of functional nanostructured materials for optimum performance. Flexible carbon nanofiber mats obtained by electrospinning are used as a current collector and cathode support for the batteries. The cathode layer consists of manganese oxide particles combined with single-walled carbon nanotubes for improved conductivity. A polyethylene oxide layer containing titanium oxide nanoparticles forms the electrolyte layer, and a thin zinc foil is used as the anode. The battery is shown to retain its performance under mechanically stressed conditions. The results show that the above configuration can achieve solid-state mechanical flexibility and increased shelf life with little sacrifice in performance.

Poly(vinylidene fluoride) (PVDF) nanofibers were prepared by electrospray deposition (ESD). To control the diameter, morphology, and structure of PVDF nanofibers, some parameters were investigated, such as polymer concentration, nozzle‐to‐ground collector distance, feeding rate of the polymer solution, and applied voltage. The fabricated fiber was 80–700 nm in diameter. The increase in the polymer concentration caused an increase in the polymer viscosity and fiber diameter. At low polymer concentration (5 wt %), polymer nanoparticles were formed. An increase in applied voltage will increase the fiber diameter. Variation in the nozzle‐to‐ground collector distance did not result in significant changes in the fiber diameter. Increase in the feeding rate of the polymer solution decreased the fiber diameter. Differential scanning calorimetry (DSC) and wide angle X‐ray diffraction (WAXD) measurements showed that the melting point and total crystallinity were decreased. Fourier transform infrared spectroscopy (FTIR) measurement revealed that ESD process induced the formation of the oriented β‐phase PVDF structures. It was also demonstrated that the addition of hydrofluorocarbon solvent to polymer solution remarkably enhanced the formation of β‐phase crystalline structure of PVDF nanofiber. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 779–786, 2006

Anionic and cationic monomers were graft-polymerized onto poly(acrylonitrile) (PAN) membrane surfaces. The graft polymerization was initiated by an oxidation−reduction system at 25 °C. Grafted PAN membrane surfaces yielded FT-IR/ATR spectra clearly different from that of an unmodified PAN membrane, because of the presence of the graft chains. ζ potentials of the pore surfaces of the grafted PAN membranes were obtained from streaming potential measurements. The surface properties are discussed with respect to a single site dissociation model, which is based on the protonation and deprotonation of charged surface groups. In this study, we obtained some characteristic parameters of the pore surfaces from the theoretical fits using the site dissociation model. This approach gives direct insight into the pore surface properties of the membrane. The results could be well explained by an ion-pairing effect in terms of different charge characteristics between membranes having hydrophobic or hydrophilic graft chains:  charge groups of hydrophobic graft chains are likely to form ion pairs with counterions from the external solution. The local dielectric constant surrounding ion pairs plays an important role in the surface effective charge concentration.

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