Self‐Construction of Efficient Interfaces Ensures High‐Performance Direct Ammonia Protonic Ceramic Fuel Cells

Abstract Direct ammonia protonic ceramic fuel cells (PCFCs) are highly efficient energy conversion devices since ammonia as a carbon‐neutral hydrogen‐rich carrier shows great potential for storage and long‐distance transportation when compared with hydrogen fuel. However, traditional Ni‐based anodes readily suffer from severe structural destruction and dramatic deactivation after long‐time exposure to ammonia. Here a Sr 2 Fe 1.35 Mo 0.45 Cu 0.2 O 6−δ (SFMC) anode catalytic layer (ACL) painted onto a Ni‐BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3− δ (BZCYYb) anode with enhanced catalytic activity and durability toward the direct utilization of ammonia is reported. A tubular Ni‐BZCYYb anode‐supported cells with the SFMC ACL show excellent peak power densities of 1.77 W cm −2 in wet H 2 (3% H 2 O) and 1.02 W cm −2 in NH 3 at 650 °C. A relatively stable operation of the cells is obtained at 650 °C for 200 h in ammonia fuel. Such achieved improvements in the activity and durability are attributed to the self‐constructed interfaces with the phases of NiCu or/and NiFe for efficient NH 3 decomposition, resulting in a strong NH 3 adsorption strength of the SFMC, as confirmed by NH 3 thermal conversion and NH 3 ‐temperature programmed desorption. This research offers a valuable strategy of applying an internal catalytic layer for highly active and durable ammonia PCFCs.