Abstract Three-phase polymer electrolyte nanocomposite composed of polyvinyl-alcohol (PVA), manganese(II) chloride (MnCl2), and multiwall carbon nanotubes (MWCNTs) were prepared using the cast techniques. Impedance spectroscopy was used to investigate AC electrical conductivity (σ ac ) two- three-phase samples with different weight ratios over a wide frequency range at various fixed temperature...

A characterization of the ionic conduction of the active layer of a polymer electrolyte membrane fuel cell ~PEMFC! cathode by ac impedance measurement at open-circuit potential conditions was conducted. Porous electrode theory was used to derive a compact equation, ]2F& 2 /]y 1 ] ln f(y)/]y 3 ]F& 2 /]y 2 R/ f (y)(1 1 jV)F& 2 5 0, to solve for the impedance response of a cathode at open-circuit ...

The freezing of water in Portland cement paste was investigated using a.c. impedance spectroscopy techniques. Length change and impedance measurements on cooling and warming were obtained simultaneously using a specially designed coupling technique. A new descriptor of frost resistance is described in terms of the high frequency arc depression angle in the impedance plane. Curves of the depress...

The present paper reports an alternate current impedance spectroscopic study on adsorption of urea (U) at Pt(100) single-crystal surface, examined in 0.5 M H2SO4 supporting electrolyte. The resulted information provided confirmation of the role of electrosorption of urea on the Pt(100) plane through evaluation of the associated charge transfer resistance and capacitance parameters. Obtained imp...