TEMPO/viologen electrochemical heterojunction for diffusion-controlled redox mediation: A highly rectifying bilayer-sandwiched device based on cross-reaction at the interface between dissimilar redox polymers

Hiroshi Tokue, Kenichi Oyaizu, Takashi Sukegawa, Hiroyuki Nishide

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

A couple of totally reversible redox-active molecules, which are different in redox potentials, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) and viologen (V2+), were employed to give rise to a rectified redox conduction effect. Single-layer and bilayer devices were fabricated using polymers containing these sites as pendant groups per repeating unit. The devices were obtained by sandwiching the redox polymer layer(s) with indium tin oxide (ITO)/glass and Pt foil electrodes. Electrochemical measurements of the single-layer device composed of polynorbornene-bearing TEMPO (PTNB) exhibited a diffusion-limited current-voltage response based on the TEMPO+/TEMPO exchange reaction, which was almost equivalent to a redox gradient through the PTNB layer depending upon the thickness. The bilayer device gave rise to the current rectification because of the thermodynamically favored cross-reaction between TEMPO+ and V+ at the polymer/polymer interface. A current-voltage response obtained for the bilayer device demonstrated a two-step diffusion-limited current behavior as a result of the concurrent V 2+/V+ and V+/V0 exchange reactions according to the voltage and suggested that the charge transport process through the device was most likely to be rate-determined by a redox gradient in the polymer layer. Current collection experiments revealed a charge transport balance throughout the device, as a result of the electrochemical stability and robustness of the polymers in both redox states.

Original languageEnglish
Pages (from-to)4043-4049
Number of pages7
JournalACS Applied Materials and Interfaces
Volume6
Issue number6
DOIs
Publication statusPublished - 2014 Mar 26

Fingerprint

Viologens
Cross Reactions
Oxidation-Reduction
Heterojunctions
Polymers
Equipment and Supplies
Charge transfer
Electric potential
Bearings (structural)
ITO glass
Metal foil
Glass
Electrodes
Molecules

Keywords

  • bilayer
  • charge transport
  • heterojunction
  • rectification
  • redox polymer
  • self-exchange reaction

ASJC Scopus subject areas

  • Materials Science(all)
  • Medicine(all)

Cite this

@article{db41a2f0ea524af092f0d1c4eb111fe8,
title = "TEMPO/viologen electrochemical heterojunction for diffusion-controlled redox mediation: A highly rectifying bilayer-sandwiched device based on cross-reaction at the interface between dissimilar redox polymers",
abstract = "A couple of totally reversible redox-active molecules, which are different in redox potentials, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) and viologen (V2+), were employed to give rise to a rectified redox conduction effect. Single-layer and bilayer devices were fabricated using polymers containing these sites as pendant groups per repeating unit. The devices were obtained by sandwiching the redox polymer layer(s) with indium tin oxide (ITO)/glass and Pt foil electrodes. Electrochemical measurements of the single-layer device composed of polynorbornene-bearing TEMPO (PTNB) exhibited a diffusion-limited current-voltage response based on the TEMPO+/TEMPO exchange reaction, which was almost equivalent to a redox gradient through the PTNB layer depending upon the thickness. The bilayer device gave rise to the current rectification because of the thermodynamically favored cross-reaction between TEMPO+ and V+ at the polymer/polymer interface. A current-voltage response obtained for the bilayer device demonstrated a two-step diffusion-limited current behavior as a result of the concurrent V 2+/V+ and V+/V0 exchange reactions according to the voltage and suggested that the charge transport process through the device was most likely to be rate-determined by a redox gradient in the polymer layer. Current collection experiments revealed a charge transport balance throughout the device, as a result of the electrochemical stability and robustness of the polymers in both redox states.",
keywords = "bilayer, charge transport, heterojunction, rectification, redox polymer, self-exchange reaction",
author = "Hiroshi Tokue and Kenichi Oyaizu and Takashi Sukegawa and Hiroyuki Nishide",
year = "2014",
month = "3",
day = "26",
doi = "10.1021/am405527y",
language = "English",
volume = "6",
pages = "4043--4049",
journal = "ACS applied materials & interfaces",
issn = "1944-8244",
publisher = "American Chemical Society",
number = "6",

}

TY - JOUR

T1 - TEMPO/viologen electrochemical heterojunction for diffusion-controlled redox mediation

T2 - A highly rectifying bilayer-sandwiched device based on cross-reaction at the interface between dissimilar redox polymers

AU - Tokue, Hiroshi

AU - Oyaizu, Kenichi

AU - Sukegawa, Takashi

AU - Nishide, Hiroyuki

PY - 2014/3/26

Y1 - 2014/3/26

N2 - A couple of totally reversible redox-active molecules, which are different in redox potentials, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) and viologen (V2+), were employed to give rise to a rectified redox conduction effect. Single-layer and bilayer devices were fabricated using polymers containing these sites as pendant groups per repeating unit. The devices were obtained by sandwiching the redox polymer layer(s) with indium tin oxide (ITO)/glass and Pt foil electrodes. Electrochemical measurements of the single-layer device composed of polynorbornene-bearing TEMPO (PTNB) exhibited a diffusion-limited current-voltage response based on the TEMPO+/TEMPO exchange reaction, which was almost equivalent to a redox gradient through the PTNB layer depending upon the thickness. The bilayer device gave rise to the current rectification because of the thermodynamically favored cross-reaction between TEMPO+ and V+ at the polymer/polymer interface. A current-voltage response obtained for the bilayer device demonstrated a two-step diffusion-limited current behavior as a result of the concurrent V 2+/V+ and V+/V0 exchange reactions according to the voltage and suggested that the charge transport process through the device was most likely to be rate-determined by a redox gradient in the polymer layer. Current collection experiments revealed a charge transport balance throughout the device, as a result of the electrochemical stability and robustness of the polymers in both redox states.

AB - A couple of totally reversible redox-active molecules, which are different in redox potentials, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) and viologen (V2+), were employed to give rise to a rectified redox conduction effect. Single-layer and bilayer devices were fabricated using polymers containing these sites as pendant groups per repeating unit. The devices were obtained by sandwiching the redox polymer layer(s) with indium tin oxide (ITO)/glass and Pt foil electrodes. Electrochemical measurements of the single-layer device composed of polynorbornene-bearing TEMPO (PTNB) exhibited a diffusion-limited current-voltage response based on the TEMPO+/TEMPO exchange reaction, which was almost equivalent to a redox gradient through the PTNB layer depending upon the thickness. The bilayer device gave rise to the current rectification because of the thermodynamically favored cross-reaction between TEMPO+ and V+ at the polymer/polymer interface. A current-voltage response obtained for the bilayer device demonstrated a two-step diffusion-limited current behavior as a result of the concurrent V 2+/V+ and V+/V0 exchange reactions according to the voltage and suggested that the charge transport process through the device was most likely to be rate-determined by a redox gradient in the polymer layer. Current collection experiments revealed a charge transport balance throughout the device, as a result of the electrochemical stability and robustness of the polymers in both redox states.

KW - bilayer

KW - charge transport

KW - heterojunction

KW - rectification

KW - redox polymer

KW - self-exchange reaction

UR - http://www.scopus.com/inward/record.url?scp=84896972830&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84896972830&partnerID=8YFLogxK

U2 - 10.1021/am405527y

DO - 10.1021/am405527y

M3 - Article

C2 - 24559298

AN - SCOPUS:84896972830

VL - 6

SP - 4043

EP - 4049

JO - ACS applied materials & interfaces

JF - ACS applied materials & interfaces

SN - 1944-8244

IS - 6

ER -