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Al-substituted ZnO is a potential high temperature n-type thermoelectric material. The thermoelectric properties, the morphology and the microstructure of Zn 0.98 Al 0.02 O prepared by soft chemistry synthesis were studied and compared with samples synthesised by solid state reaction. The soft chemistry method produces samples with better connectivity of the grains and less structural defects leading to a lower electrical resistivity and a higher thermal conductivity than solid state reaction. The Seebeck coefficient is not affected by the microstructure of the material. The highest value of the dimensionless Figure of Merit ZT of 0.21 is therefore reached at 1275 K for the samples from soft chemistry synthesis.

The very brittle oxygen ion conductor yttria stabilized zirconia (YSZ) is a typical solid electrolyte for miniaturized thin film fuel cells. In order to decrease the fuel cell operating temperature, the thickness of yttria stabilized zirconia thin films is reduced. Often, these thin membranes suffer from mechanical failure and gas permeability. To improve these mechanical issues, a glancing angle deposition approach is used to grow yttria stabilized zirconia thin films with tilted columnar structures. Changes of the material flux direction during the deposition result in a dense, zigzag-like structure with columnar crystallites. This structure reduces the elastic modulus of these membranes as compared to columnar yttria stabilized zirconia thin films as monitored by nano-indentation which makes them more adaptable to applied stress.