We present here results of the application and parameter optimization of the technique of solution spray pyrolysis for the fabrication of electrodic films of the type Cu-CeO 2 and La 0.75 Sr 0.25 MnO 3 (LSM) on dense pellets of the solid electrolyte yttria-stabilized zirconia (YSZ). The first type of electrode combines the properties of a good electronic conductor (Cu) and an efficient catalyst while the second constitutes a typical perovskite exhibiting mixed (i.e. ionic and electronic) conductivity. Both types of electrodes find wide use in ceramic fuel cells, gas sensors and catalytic processes.

The technique of air-pressurized solution spray pyrolysis was used to fabricate thin films of La 0.75 Sr 0.25 MnO 3 (LSM) and CuO-CeO 2 on dense YSZ substrates. These films are widely used in several applications such as high temperature ceramic electrochemical cells, membranes and sensors. The technique was tailored to produce films with differing morphologies and thicknesses in terms of applied substrate deposition temperatures. The droplet drying and decomposition kinetics is discussed as a function of substrate temperature, given the other processing parameters (i.e. nozzle to substrate distance, solution flow rate, air pressure/air flow rate and deposition time) constant. A graph-map is drawn containing morphology and quality of fabricated films in terms of substrate temperatures and concentration levels for this particular set of precursor salts in aqueous solutions. Within the deposition temperature range examined, film thicknesses were found to decrease with increasing substrate temperature along with a concomitant change in quality from irregular texture to smoother and of more uniform thickness. A maximum deposition temperature of about 280 • C was identified for 0.025M concentration for both types of films which correlates quite well with the Leidenfrost point measured in the literature for solvents with boiling point less than 150 • C.

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