A high-performance and durable direct NH3 tubular protonic ceramic fuel cell integrated with an internal catalyst layer

Nickel-based cermet anode-supported protonic ceramic fuel cells (PCFCs) show great potential for direct utili-zation of ammonia. However, the insufficient activity of anode and the deterioration of anode activity/durability caused by the undesired interaction between nickel and ammonia greatly limit the application. Here, we report tubular PCFCs embedded with a catalytic iron layer. Such cells show peak power densities of 1.507 W cm(-2) and 1.078 W cm(-2) at 700 ? when using H-2 and NH3 as fuel, respectively, which are the highest tubular PCFC performance so far ever reported. In addition, the stability of cells with the catalyst layer has been dramatically enhanced when compared with that of cells without the catalyst layer. The enhancement of activity and durability is attributed to the catalytic activity of iron for ammonia decomposition, through which the direct contact between nickel and ammonia has been minimized and the anode structure has therefore been protected.