at Google ScholarTitle data
Paulus, Daniel ; Schönauer-Kamin, Daniela ; Moos, Ralf:
Microstructural investigations on aerosol-deposited Calcium Cobaltite films revealing the outstanding thermoelectric properties and the deposition mechanism.
2024
Event: 14th International Conference on Ceramic Materials and Components for Energy and Environmental Systems
, 18-22 August 2024
, Budapest, Hungary.
(Conference item: Conference
,
Speech
)
Abstract in another language
Powder aerosol deposition (PAD) is a coating process that can be used to produce ceramic coatings at room temperature. In this process, powder aerosols generated in an aerosol gen- erator are accelerated through a nozzle into a vacuum chamber. In the vacuum chamber, the ceramic particles hit a substrate and form a dense layer of a nanocrystalline ceramic. This process works with most technical ceramics such as aluminum oxide or yttria-stabilized zirconia (YSZ). It is also possible to produce films of functional ceramics. Examples are the cathode active material nickel manganese cobalt oxide (NMC), ion conductors such as sodium super ionic conducters (NASICON) or lithium lantanum zirconium oxide (LLZO), or thermoelectric materials bismuth telluride, copper-iron delafossite or the misfit-layered oxide calcium cobaltite Ca3Co4O9 (CCO). The latter are particularly notable for their very high deposition rate in the PAD process. In this work, CCO powder is prepared via the mixed oxide route and films are produced by the powder aerosol deposition method. The microstructure of these films is investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) and these results are correlated with the resulting thermoelectric properties (Seebeck coefficient and electrical conductivity). The results show that the films do not have a typical PAD microstructure, but that the crystals are significantly larger and platelet-like shaped. XRD investigations confirma strong fiber texture of the PAD-CCO films. The fiber texture is expressed in the fact that the vast majority of crystals are oriented with the [001] direction perpendicular to the substrate plane. This explains the comparatively high electrical conductivity and the comparatively high Seebeck coefficient of the CCO-PAD film investigated in-plane direction, as the electrical conductivity in CCO crystals in the (001) plane is many times higher than perpendicular to it. Finally, considerations on the possible deposition mechanism for materials with layered and misfitted crystal structure are presented, through which the texture of the films is achieved.
Further data
| Item Type: | Conference item (Speech) |
|---|---|
| Refereed: | Yes |
| Institutions of the University: | Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Functional Materials > Chair Functional Materials - Univ.-Prof. Dr.-Ing. Ralf Moos Profile Fields > Advanced Fields > Advanced Materials Research Institutions > Central research institutes > Bayreuth Center for Material Science and Engineering - BayMAT |
| Result of work at the UBT: | Yes |
| DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
| Date Deposited: | 19 Sep 2024 05:39 |
| Last Modified: | 19 Sep 2024 05:39 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/90435 |