Synthesis and charge-transport properties of polymers derived from the oxidation of 1-hydro-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridium Bis(hexafluorophosphate) and demonstration of pH-sensitive microelectrochemical transistor derived from the redox properties of a conventional redox center

Journal Article · Thu Sep 08 00:00:00 EDT 1988 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100329a031· OSTI ID:6221243

Shu, C F; Wrighton, M S

This article describes the synthesis and electrochemical properties of redox polymers, having a polypyrrole backbone and viologen subunits, derived from oxidative electropolymerization of 1-methyl-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridinium (P-V-Me/sup 2 +/) and 1-hydro-1'-(6-(pyrrol-1-yl)hexyl)-4,4'-bipyridinium (P-V-H/sup 2 +/). Closely spaced (approx. 1.5 ..mu..M) Au microelectrode arrays (approx. 2.5 ..mu..m wide /times/ 50 ..mu..m long /times/ 0.1 ..mu..m high) modified with the polymers can be used to study aspects of the charge-transport behavior of the viologen redox system. Poly(P-V-Me/sup 2 +/) have been used to investigate the characteristics of microelectrochemical transistors based on a viologen redox center and a similar redox center, protonated, monoquaternized bipyridinium, which is pH dependent. The interesting properties from poly(P-V-Me/sup 2 +/) and poly(P-V-H/sup 2 +/) stem from behavior of the pendant viologen redox centers. The device based on poly(P-V-Me/sup 2 +/) has a narrow region (approx. 200 mV) of gate voltage, V/sub G/, where the source-drain current, I/sub D/, is nonzero and has a sharp, pH-independent peak in the I/sub D/-V/sub G/ plot at approx. 0.53 V versus SCE associated with the reversible, one-electron reduction of viologen. This result is consistent with electron self-exchange between redox centers being the mechanism for charge transport. The device based on poly(P-V-H/sup 2 +/) shows a pH-dependent I/sub D/ at fixed V/sub G/, as expected from the electrochemical behavior from reversible protonation of the terminal N of the bipyridinium group of poly(P-V-H/sup 2 +/). The microelectrochemical transistor based on poly(P-V-H/sup 2 +/) illustrates the design of chemically sensitive, molecule-based devices using conventional redox materials.

• Research Organization: Massachusetts Institute of Technology, Cambridge (USA)
• OSTI ID: 6221243
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 92:18; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400400 -- Electrochemistry
42 ENGINEERING
420800 -- Engineering-- Electronic Circuits & Devices-- (-1989)
AZINES
BIPYRIDINES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
DATA
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PERFORMANCE
PH VALUE
PHOSPHATES
PHOSPHORUS COMPOUNDS
PYRIDINES
SEMICONDUCTOR DEVICES
SYNTHESIS
TRANSISTORS
VOLTAMETRY