Flame assisted vapour deposition of cathode for solid oxide fuel cells. 1. Microstructure control from processing parameters

The flame assisted vapour deposition (FAVD) technique has been used to deposit porous lanthanum strontium manganese oxide (LSM) to produce the cathode for a solid oxide fuel cell (SOFC). FAVD combines flame synthesis and vapour deposition methods where the liquid precursor undergoes a combustion process into a vapour phase, and then deposits as an oxide film on a substrate. The work has shown that the microstructures of deposited films may be dense or porous depending on processing parameters such as the deposition temperature, the concentration of the fuel and the distance between the spray nozzle and the substrate. A mechanism for the effects of these processing parameters interpreted as ‘the combustion zone’ has been proposed. This mechanism is used to explain the physical properties of films which were characterised using SEM and XRD. The FAVD technique is shown to be an efficient way in which SOFCs’ cathode film can be fabricated with tailoring of the desired phases and microstructure.