Direct evidence for fixed ionic groups in the hydrogel of an electrolyte diode

文献情報

出版日 2002-02-22

DOI 10.1039/B109016J

インパクトファクター 3.676

著者

Kristóf Iván, Norbert Kirschner, Mária Wittmann, Viktor Jakab, Zoltán Noszticzius, John H. Merkin, Stephen K. Scott

原文を見る

要旨

Current–voltage characteristics of polyvinyl alcohol (PVA)–glutardialdehyde hydrogel cylinders were measured in dilute KCl solutions. The gel was the same type which had been applied in previous electrolyte diode experiments. Below 10−2 molar KCl concentration the measured characteristics were nonlinear and at higher voltages the current was unstable. These results were explained by concentration polarization phenomena due to fixed negative charges present in the hydrogel and by electroconvection in the anodic boundary layer of the gel cylinder where a strong electric field can appear. To confirm these hypotheses further experiments were performed where spatially resolved concentration polarization data could be obtained inside the gel and in its close neighbourhood. The proposed model was also supported with semi-quantitative simulations which were able to reproduce the measured nonlinear characteristics and the observed concentration polarization phenomena. The fixed negative charges are most probably ionized carboxylic acid groups contaminating the PVA and the PVA-based hydrogel.

掲載誌

Physical Chemistry Chemical Physics

CiteScore: 5.5

自己引用率: 10.3%

年間論文数: 3036

Physical Chemistry Chemical Physics (PCCP) is an international journal co-owned by 19 physical chemistry and physics societies from around the world. This journal publishes original, cutting-edge research in physical chemistry, chemical physics and biophysical chemistry. To be suitable for publication in PCCP, articles must include significant innovation and/or insight into physical chemistry; this is the most important criterion that reviewers and Editors will judge against when evaluating submissions. The journal has a broad scope and welcomes contributions spanning experiment, theory, computation and data science. Topical coverage includes spectroscopy, dynamics, kinetics, statistical mechanics, thermodynamics, electrochemistry, catalysis, surface science, quantum mechanics, quantum computing and machine learning. Interdisciplinary research areas such as polymers and soft matter, materials, nanoscience, energy, surfaces/interfaces, and biophysical chemistry are welcomed if they demonstrate significant innovation and/or insight into physical chemistry. Joined experimental/theoretical studies are particularly appreciated when complementary and based on up-to-date approaches.