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Solid oxide cell electrodes need to display a wide range of combined properties, for example, electronic and ionic conductivities, catalytic activity, chemical compatibility with other parts, thermal expansion match, phase stability, and tolerance to foreign species/contaminants. It is extremely challenging for a single material to meet all these features required. Surface decoration is a remarkably adaptive strategy to provide needed features to the electrodes by introducing functioning materials through various target‐guided methods. This review provides an overview of typical and novel techniques to create surface decoration on the electrodes to abruptly improve the drawbacks of the electrodes of solid oxide cells, including performance enhancement, stability of long‐term operation, and tolerance to poisoning foreign species. It starts with the introduction of surface decoration experimental procedure, proceeds to crucial characterization methods that are particularly effective in identifying the properties of the surface coating, continues with target‐oriented practice in terms of surface decoration materials choice and microstructure manipulation, and ends with the explorations of functioning mechanisms for the resultant behavior. With hope, the review will spark more novel utilizations of surface decoration practice to promote the technical status of the solid oxide cells for widespread commercialization in the future. [ABSTRACT FROM AUTHOR]

In the current work, we investigate the performance of solid oxide fuel cells (SOFCs) with Ni‒yttria-stabilized zirconia (Ni–YSZ) and Ni‒gadolinia-dope ceria (Ni–GDC) cermet anodes fueled with H 2 or NH 3 in terms of the catalytic activity of ammonia decomposition. The cermet of Ni–GDC shows higher catalytic activity for ammonia decomposition than Ni–YSZ. In response to this, the performance of direct NH 3 –fueled SOFC improved by using Ni–GDC anode. Moreover, we observe further enhancement in the cell performance and the catalytic activity for ammonia decomposition with applying Ni−GDC anode synthesised by the glycine–nitrate combustion process. These results reveal that the high performance of Ni–GDC anode for the direct NH 3 –fueled SOFC results from its mixed ionic–electronic conductivity as well as high catalytic activity for ammonia decomposition. [ABSTRACT FROM AUTHOR]

In this study the electrochemical performances of Ni-YSZ anode in humidified H2, NH3 and CH4 fuels were compared under almost the same partial pressure of oxygen at 500-800°C. The cell performance was significantly affected by fuel species and operating temperature. The single cell exhibited higher performance in wet NH3 as compared with that in CH4, which was caused by the difference in the catalytic activity of anode for the hydrogen production in wet NH3 and CH4 . Thus, it was clarified that NH3 is a preferable fuel rather than CH4 for the direct use in SOFCs. Furthermore, the kinetics study on ammonia decomposition over Ni-YSZ anode was conducted at 600°C. Although the ammonia decomposition increased with increasing ammonia concentration, the decomposition reduced in the presence of hydrogen in the reactant gas. Such a behavior was not confirmed at 850°C. These results indicated the inhibition effect of hydrogen for ammonia decomposition, which will be the key factor for the design of anode and the operating condition setting. [ABSTRACT FROM AUTHOR]