Piezoelectric transformers have become an attractive alternative solution for cold plasma generation. Their high efficiency, thin-shaped dimensions and low voltage supply make them serious and original candidates for numerous low power applications, particularly in biomedical field.
The ability of these ferroelectric materials to generate high electric field through a simple mechanical action has been known for a long time and applied in basic ignition systems such as lighters. Whereas piezoelectric properties were first harnessed to spark generation, nowadays they are used to maintain the surrounding gas in a plasma state. The development of such devices requires gaining insight on the ceramic behavior while involved in the discharge.
The piezoelectric and ferroelectric properties of these materials are conditioned by the domains arrangements. Since the ferroelectric processes depend significantly on the microstructure, it becomes important to characterize the ceramics on a micronic or even submicronic scale, both in bulk and surface, and link these characterizations to the ceramics behavior: their electromechanical properties and structures on these scales are thus of particular interest.
This presentation focuses on the correlation between the material structure and its electrical properties based on a multi-scale characterization methodology, before and after plasma discharge. Moreover, it is aimed at better understanding the physical phenomena involved during the discharge and identifying the resulting damages on the material surface.
The study mainly focuses on the surface evolution of the crystalline structure and the chemical composition (Raman mapping, X-ray diffraction, EPMA, XPS), related to the overall properties of the piezoelectric transformer (electrical parameters, operating frequency) before and after discharge generation.
Energy Generation (SOFC, PCFC, PV, ...) , Piezoelectrics , (Micro)structure-property relations , Other
