Fabrication of nickel oxide-yttria stabilized zirconia films by electrostatic spray deposition

The commonly used NiO-YSZ cermet is known to have many desirable properties for the anode of solid oxide fuel cells (SOFCs), such as high electronic and ionic conductivity, high electrochemical activity, and good microstructural stability. When used as an anode of an SOFC, the critical factor determining the performance of the NiO-YSZ composite material is the porosity and pore size to ensure a large enough effective surface area for electrochemical oxidation. In this study, electrostatic spray deposition (ESD) was applied to fabricate a porous film of a NiO-YSZ cermet. An ESD system has several advantages over the conventional thick film process, such as creating a uniform coating for large areas, in expensive and simple equipment, high synthesis efficiency, fast deposition rate, a diversity of raw materials selection, operation at atmospheric conditions, and easy control of deposition rate and film thickness. A solution of NiO-YSZ (NiO- 8 mol% yttria stabilized zirconia) in methanol was sprayed onto the anode substrate surface at 350-500 degrees C by ESD. The Porosity and microstructure were controlled by changing the deposition process parameters and the sintering temperature. The deposition parameters studied were substrate temperature, distance between nozzle and substrate, deposition time and DC voltage.