The University of Southampton
University of Southampton Institutional Repository

Development of a Potentiometric carbon dioxide gas sensor

Development of a Potentiometric carbon dioxide gas sensor
Development of a Potentiometric carbon dioxide gas sensor

Research was undertaken to develop a fast responding, low power carbon dioxide gas sensor. A review of current technologies was undertaken and the Severinghaus design was selected. The technologies used in the Severinghaus design where analysed and researched section by section so as to be improved upon. This involved looking at the pH-sensing electrode, the reference electrode and the electrolyte as well as overall design/shape of the sensor.

Various metal - metal oxides were looked at for the pH sensing including palladium and iridium and thin film polyaniline was also tested. Tests included linearity, lifetime and speed. Different ways of synthesising the metal oxide electrodes were also investigated, including thermal and electrochemical oxidation. The shape and form of the original metal was also modified from wire, foil, and thin film from sputtering and electroplating. Several electrolytes were tested including amorphous polyethylene oxide (APEO) and a silicone-based polymer. The polymers were tested when made up into the carbon dioxide sensor and exposed to differing relative humidities.

Iridium/iridium oxide and polyaniline were found to be the most stable and reliable pH sensing materials for this purpose. When combined with an Ag/AgCl reference electrode and the silicone polymer in a thin film design layout the best performing sensor was obtained with a T90 time of less than 60 seconds. The best sensor lifetime obtained was 7 days before the polymer electrolyte was poisoned. If the electrolyte was replaced then the sensor's sensitivity was restored.

University of Southampton
Pilling, Michael G
Pilling, Michael G

Pilling, Michael G (2002) Development of a Potentiometric carbon dioxide gas sensor. University of Southampton, Doctoral Thesis.

Record type: Thesis (Doctoral)

Abstract

Research was undertaken to develop a fast responding, low power carbon dioxide gas sensor. A review of current technologies was undertaken and the Severinghaus design was selected. The technologies used in the Severinghaus design where analysed and researched section by section so as to be improved upon. This involved looking at the pH-sensing electrode, the reference electrode and the electrolyte as well as overall design/shape of the sensor.

Various metal - metal oxides were looked at for the pH sensing including palladium and iridium and thin film polyaniline was also tested. Tests included linearity, lifetime and speed. Different ways of synthesising the metal oxide electrodes were also investigated, including thermal and electrochemical oxidation. The shape and form of the original metal was also modified from wire, foil, and thin film from sputtering and electroplating. Several electrolytes were tested including amorphous polyethylene oxide (APEO) and a silicone-based polymer. The polymers were tested when made up into the carbon dioxide sensor and exposed to differing relative humidities.

Iridium/iridium oxide and polyaniline were found to be the most stable and reliable pH sensing materials for this purpose. When combined with an Ag/AgCl reference electrode and the silicone polymer in a thin film design layout the best performing sensor was obtained with a T90 time of less than 60 seconds. The best sensor lifetime obtained was 7 days before the polymer electrolyte was poisoned. If the electrolyte was replaced then the sensor's sensitivity was restored.

Text
842417.pdf - Version of Record
Available under License University of Southampton Thesis Licence.
Download (31MB)

More information

Published date: 2002

Identifiers

Local EPrints ID: 464671
URI: http://eprints.soton.ac.uk/id/eprint/464671
PURE UUID: 455ef2de-a690-4387-a5f4-9d7a0a4918e0

Catalogue record

Date deposited: 04 Jul 2022 23:55
Last modified: 05 Jul 2022 02:51

Export record

Contributors

Author: Michael G Pilling

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×