Buffer-layer solid oxide fuel cells for direct-ammonia operation: An analysis of electrical performance and exhaust composition

Hydrogen fuel is a very effective fuel source when the storage volume does not have strict space requirements. However, many applications of hydrogen fuel would be better served by a hydrogen carrier gas which requires a smaller storage volume for the same energy capacity. In many combustion processes, a hydrogen carrier such as ammonia would require a dedicated catalytic device to reform the ammonia into hydrogen for the combustion process. The use of solid oxide fuel cells (SOFC) may eliminate the need for a dedicated catalyst due to the inherent ability of the SOFC anode layer to carry out thermal cracking of ammonia. This work will discuss the performance characteristics of a direct-ammonia SOFC using the novel application of a SDC buffer-layer construction type. With a peak power density of 399mW/cm 2 at 750°C operational temperature, the direct-ammonia buffer-layer (DABL) SOFC has proven to be successful for ammonia operation in low temperature regimes. Additionally, this study highlights the exhaust composition obtained from direct-ammonia operation, with a key point of interest being the low nitric oxide content at low operational temperatures.