Characterization of a solid-state microelectrochemical diode employing a poly(vinyl alcohol)/phosphoric acid solid-state electrolyte: Rectification at junctions between WO sub 3 and polyaniline

Journal Article · · Chemistry of Materials; (United States)

DOI:https://doi.org/10.1021/cm00011a020· OSTI ID:5402259

Leventis, N; Schloh, M O; Natan, M J; Hickman, J J; Wrighton, M S ^[1]

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1. Massachusetts Institute of Technology, Cambridge (USA)

The functionalization of an array of eight, closely spaced ({approximately}1.2 {mu}m) Pt or Au microelectrodes each {approximately}50 {mu}m long, 2 {mu}m wide, and 0.1 {mu}m thick with redox-active WO{sub 3} and polyaniline and the electrochemical characterization of the WO{sub 3}/polyaniline junction are reported. Chips consisting of microfabricated WO{sub 3} covering three of the available eight microelectrodes have been analyzed by Auger electron spectroscopy. The remaining five microelectrodes are available for further derivatization with polyaniline or can function as counterelectrodes. By placing a counterelectrode and a Ag quasi-reference electrode directly on the microchip and by coating the assembly with a thin film of poly(vinyl alcohol)/H{sub 3}PO{sub 4} solid polymeric electrolyte, the electrochemical system becomes self-contained. The solid polymer electrolyte is a good room-temperature H{sup +} conductor only when exposed to a H{sub 2}O-containing atmosphere. Complex impedance studies show as much as a 10{sup 3} change in H{sup +} conductivity from H{sub 2}O-saturated to H{sub 2}O-free gaseous atmosphere above the polymer electrolyte. The changes in conductivity of WO{sub 3} upon reduction or polyaniline upon oxidation allow demonstration of solid-state microelectrochemical transistors with these materials. The combination of WO{sub 3} and polyaniline on the chip allows demonstration of a microelectrochemical diode.

• OSTI ID: 5402259
• Journal Information: Chemistry of Materials; (United States), Vol. 2:5; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
ELECTRODES
FABRICATION
AUGER ELECTRON SPECTROSCOPY
MICROELECTRONICS
ORGANIC POLYMERS
PHOSPHORIC ACID
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR DIODES
SOLID ELECTROLYTES
ELECTROLYTES
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
HYDROGEN COMPOUNDS
INORGANIC ACIDS
MICROSCOPY
ORGANIC COMPOUNDS
POLYMERS
SEMICONDUCTOR DEVICES
SPECTROSCOPY
426000* - Engineering- Components
Electron Devices & Circuits- (1990-)