title: Electrochemical mechanism of ion current rectification of polyelectrolyte gel diodes.
abstract: Polyelectrolyte gel diodes that are double layers of two oppositely charged polyelectrolyte gels, sandwiched by two symmetric electrodes, are emergent ionic devices. These diodes are designed to rectify ion currents with a physical mechanism that is analogous to conventional semiconductor diodes-the asymmetry in the permeability of ions across the interfaces between the two oppositely charged gels. Here we show that polyelectrolyte gel diodes indeed rectify steady currents with a physical mechanism that is very different from conventional diodes by using a simple electrochemical model; electric currents are limited by electrochemical reactions that are driven by potential drops at electrodes and these potential drops markedly change with changing the direction of applied voltages due to the redistribution of non-reactive counterions, leading to rectified ion currents. This concept is relatively generic and thus may provide insight in the physics of analogous ionic and biomimetic systems that show electrochemical reactions.
authors.affiliation: 1] Center of Soft Matter Physics and its Applications, School of Chemistry and Environment, Beihang University, Xueyuan Road 37, Beijing 100191, China [2] Kavli Institute for Theoretical Physics China, Zhong Guan Cun East Street 55, Beijing 100190, China [3] Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1, O-okayama, Meguro-ku, Tokyo 152-8552, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Center of Soft Matter Physics and its Applications, School of Chemistry and Environment, Beihang University, Xueyuan Road 37, Beijing 100191, China.
authors.forename: Masao
authors.initials: M
authors.lastname: Doi