Dielectric Relaxation on the Intermediate Layer in a Bipolar Membrane under the Water Splitting Phenomenon: I. Shift of the Dielectric Properties by Means of Time-Dependent Impedance Measurements

✍ Scribed by Toshihisa Osaki; Akihiko Tanioka

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 158 KB
• Volume: 253
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.2002.8509

✦ Synopsis

In this study, we examined the dielectric properties of an intermediate layer in a bipolar membrane, which is composed of a negatively charged layer and a positively charged layer joined in series. As a result of the time-dependent impedance measurements of charged membranes, the negative increment in electric conductivity and the positive increment in electric capacity were observed only in the case of a bipolar membrane under the application of reverse-biased voltages, which were quite different from the behavior of both monopolar membranes and of a bipolar membrane under forward-biased voltages. Further, the observed shifts showed a nearly constant value against the reverse-biased voltage. It is concluded that these characteristics coincide with the process of ion exclusion in the intermediate layer and are attributed to the water splitting mechanism.