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Research was conducted to analyze the current-voltage relations, point defect distribution and internal electric fields in polymers. Polymer electrochemical cells with ion blocking electrodes were claimed to emit light under applied voltage. The polymer is regarded as a mixed-ionic-electronic conductor. Two relevant defect models are examined. A good fit is obtained between theory and experimental data which also considers electrode overpotentials.

Current-voltage relations, electric field, and charge distribution profiles are calculated for a device in which the dopants are mobile. The thin film limit is discussed. The model solved is restricted to: (a) mobile holes and acceptors, (b) steady state, and (c) metal electrodes which block the ionic current. The solution is expressed as a series expansion in the small parameter δ=L/λD, where L is the sample thickness and λD is a Debye length. The second order of the series expansion is found to vanish, thus the corrections to the leading order appear only in the third term. The approximated analytic solution agrees with numerical results from a previous publication up to the quite high value of δ=1. The leading order in the I-V relations and in the hole distribution is independent of the acceptor motion. This implies that for thin devices of this form any motion of the dopants may be neglected and that dopants need not be limited only to those which exhibit low diffusion constants. Rectification is observed as long as asymmetry is introduced by two different contact potentials. This holds whether the contacts lead to depletion or accumulation. [ABSTRACT FROM AUTHOR]

A theoretical and experimental study was done on current-voltage relations on circular samples with four equally spaced semicircle electrodes. The expression given for the dependence of the two-point resistance on the elctrode size, sample radius and thickness was combined with a four-point van der Pauw conductivity measurement to determine the electrode overpotential. The results of I-V relations in a thin carbon layer are also presented.

Presents a study that used thermal electromotive force (EMF) to follow phase transitions in a specimen. Discussion on the differential thermal analysis of individual specimens by thermal EMF measurement; Observation on temperature difference between specimens; Result of the study.

Presents a study which measured the chemical potential of oxygen in nonstoichiometric ceria using a novel solid eletrochemical cell. Importance of investigating thermodynamic properties of an oxide to determine the chemical potential of oxygen; Problem with previous attempts to build a solid electrochemical cell based on yttrium stabilized zirconia; Characteristics of the cell constructed.