Shop : Details
Shop
Details
48,80 €ISBN 978-3-8440-3230-7Paperback170 Seiten75 Abbildungen252 g21 x 14,8 cmEnglischDissertation
Dezember 2014
Sven Rank
The Influence of the Electrode Material on the Sensor Characteristics of SnO2 Thick Film Gas Sensors
A chemoresistive SnO₂ based gas sensor allows for measuring the resistance of the sensing layer between two electrodes in order to provide information about the chemical composition of the ambient atmosphere.
It is well documented that besides making possible the resistance measurement, the noble metal electrodes have an impact on the sensing performance because of various reasons. Some of them are purely electric in nature - the electrode gap determines the number of grain-grain boundaries - but there is also an important chemical influence due to the catalytic processes taking place at the three phase boundary: electrode/metal oxide/ambient atmosphere. By only measuring the sensor resistance one experiences all those influences but one also lacks the needed information to be able to understand their causes and the way in which it would be possible to use them.
In this work we report on operando measurements performed on screen printed thick-film SnO₂ sensors on Al₂O₃ substrates and on the corresponding model systems for the electrode-metal oxide interface: mixtures between SnO₂ powders and micrometric Au and Pt powders. The measurements were performed in dry and humid air backgrounds in the presence of various CO, H₂ and oxygen concentrations. The experimental methods are DC electrical measurements, catalytic conversion experiments and DRIFTS measurements.
Thus it could be shown, that for sensors with gold electrodes at lower working temperatures, the activation of the oxygen adsorption and the resulting increase of ionosorbed oxygen, makes the sensor more capable for reaction with gases like CO and H₂. Sensors with platinum electrodes, on the other hand, show decreased signals at selected temperatures because of the direct conversion at the noble metal electrodes.
It is well documented that besides making possible the resistance measurement, the noble metal electrodes have an impact on the sensing performance because of various reasons. Some of them are purely electric in nature - the electrode gap determines the number of grain-grain boundaries - but there is also an important chemical influence due to the catalytic processes taking place at the three phase boundary: electrode/metal oxide/ambient atmosphere. By only measuring the sensor resistance one experiences all those influences but one also lacks the needed information to be able to understand their causes and the way in which it would be possible to use them.
In this work we report on operando measurements performed on screen printed thick-film SnO₂ sensors on Al₂O₃ substrates and on the corresponding model systems for the electrode-metal oxide interface: mixtures between SnO₂ powders and micrometric Au and Pt powders. The measurements were performed in dry and humid air backgrounds in the presence of various CO, H₂ and oxygen concentrations. The experimental methods are DC electrical measurements, catalytic conversion experiments and DRIFTS measurements.
Thus it could be shown, that for sensors with gold electrodes at lower working temperatures, the activation of the oxygen adsorption and the resulting increase of ionosorbed oxygen, makes the sensor more capable for reaction with gases like CO and H₂. Sensors with platinum electrodes, on the other hand, show decreased signals at selected temperatures because of the direct conversion at the noble metal electrodes.
Schlagwörter: SnO2; thick film; gas sensor; electrode
Verfügbare Online-Dokumente zu diesem Titel
DOI 10.2370/9783844032307
Sie benötigen den Adobe Reader, um diese Dateien ansehen zu können. Hier erhalten Sie eine kleine Hilfe und Informationen, zum Download der PDF-Dateien.
Bitte beachten Sie, dass die Online-Dokumente nicht ausdruckbar und nicht editierbar sind.
Bitte beachten Sie auch weitere Informationen unter: Hilfe und Informationen.
Bitte beachten Sie auch weitere Informationen unter: Hilfe und Informationen.
| Dokument |  | Abstract / Kurzzusammenfassung | ||
| Dateiart |  | |||
| Kosten |  | frei | ||
| Aktion |  | Download der Datei | ||
| Dokument |  | Gesamtdokument | ||
| Dateiart | | |||
| Kosten |  | 36,60 € | ||
| Aktion |  | Zahlungspflichtig kaufen und download der Datei | ||
| Dokument |  | Inhaltsverzeichnis | ||
| Dateiart | | |||
| Kosten | | frei | ||
| Aktion | | Download der Datei | ||
Benutzereinstellungen für registrierte Online-Kunden (Online-Dokumente)
Sie können hier Ihre Adressdaten ändern sowie bereits georderte Dokumente erneut aufrufen.
Benutzer
Nicht angemeldet
Export bibliographischer Daten
Shaker Verlag GmbH
Am Langen Graben 15a
52353 Düren
Am Langen Graben 15a
52353 Düren
Mo. - Do. 8:00 Uhr bis 16:00 Uhr
Fr. 8:00 Uhr bis 15:00 Uhr
Fr. 8:00 Uhr bis 15:00 Uhr
Kontaktieren Sie uns. Wir helfen Ihnen gerne weiter.
