bei Google ScholarTitelangaben
Hürland, Armin ; Plog, Carsten ; Moos, Ralf ; Simon, Ulrich:
Stress-reduced NO+ conducting β"-alumina ceramic membranes.
2001
Veranstaltung: International Congress on Advanced Materials, their Processes and Applications
, 01.-04. Oktober 2001
, München.
(Veranstaltungsbeitrag: Kongress/Konferenz/Symposium/Tagung
,
Poster
)
Abstract
In this study the preparation of dense ceramic nitrosyl (NO+) cation conducting β"-alumina membranes for the preparation of selective NOx sensors is investigated. The exchange of the mobile cation (Na+) in Na-β"-alumina by a larger cation (K+, NO+) leads to an anisotropic expansion of the c-axis. The stress development was calculated using the changed lattice parameters of the two β"-alumina phases (Na+, NO+) leading to ~300 MPa. Stress induced fractures were observed using light and scanning electron microscopy. Stress-reduced dense NO+ ion conducting β-alumina membranes were produced in two different ways. The ions are exchanged only in crystals with preferred orientation forming NO+ ion conducting paths. This is achieved by placing Na-β"-Al2O3 discs with porous gold electrodes in a NO atmosphere and applying a voltage of U>2V. Cathodic oxidation of NO to NO+ occurs. Driven by the voltage difference Na+ is replaced by NO+ in preferred orientated crystals. In a second approach the ion exchange is performed in two steps. At first Na+ is replaced by K+ in a KCl melt at 1200°C to reduce stress formation. Then, the exchange of K+ by NO+ is performed in a NOCl·AlCl3 melt. Sensor measurements confirm, that both routines are suitable to manufacture crack free NO+ ion conducting ceramic β"-Al2O3 membranes.
Weitere Angaben
| Publikationsform: | Veranstaltungsbeitrag (Poster) |
|---|---|
| Begutachteter Beitrag: | Ja |
| Institutionen der Universität: | Fakultäten > Fakultät für Ingenieurwissenschaften Fakultäten > Fakultät für Ingenieurwissenschaften > Lehrstuhl Funktionsmaterialien > Lehrstuhl Funktionsmaterialien - Univ.-Prof. Dr.-Ing. Ralf Moos Fakultäten Fakultäten > Fakultät für Ingenieurwissenschaften > Lehrstuhl Funktionsmaterialien Profilfelder > Advanced Fields > Neue Materialien Forschungseinrichtungen > Forschungszentren > Bayreuther Materialzentrum - BayMAT Profilfelder Profilfelder > Advanced Fields Forschungseinrichtungen Forschungseinrichtungen > Forschungszentren |
| Titel an der UBT entstanden: | Nein |
| Themengebiete aus DDC: | 600 Technik, Medizin, angewandte Wissenschaften > 620 Ingenieurwissenschaften |
| Eingestellt am: | 06 Jul 2015 14:42 |
| Letzte Änderung: | 13 Nov 2015 10:16 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/15740 |