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A NiMo‐ceria‐zirconia catalyst was developed for an inert‐substrate‐supported tubular single cell running on isooctane fuel. The tubular single cell consisted of an inert porous yttira‐stabilized zirconia (YSZ) supporter, Ni‐Ce0.8Sm0.2O1.9 (Ni‐SDC) anode, YSZ/SDC bilayer electrolyte and La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) cathode. The NiMo‐ceria‐zirconia catalyst was packed in the tubular channel of the single cell as a reforming unit. With application of the catalyst in the tubular cell, the mixture of isooctane and air can be efficiently reformed to simple syngas (a mixture of hydrogen and carbon monoxide) at 750 °C. Compared to electrochemical performance of the single cell without the catalyst, applying the catalyst increased maximum power density of the single cell from 240 to 306 mW cm−2, and the single cell exhibited significantly improved stability during the 18 h performance test. The results suggest the feasibility of applying the NiMo‐ceria‐zirconia catalyst for operating the tubular single cell using isooctane fuel. Heterogenous Catalysis in Fuel Cells: A liquid‐fuel solid oxide fuel cell has been successfully demonstrated. By applying a novel NiMo‐ceria‐zirconia reforming catalyst in the tubular cell, complex liquid fuels can be efficiently reformed into synthesis gas before electrochemical oxidation. The internal reforming unit acts as a fuel‐cleaning filter, which significantly suppresses carbon deposition and improves the cell lifetime. [ABSTRACT FROM AUTHOR]

Molybdenum carbide (Mo2C), an interstitial transition metal carbide, has been used in a myriad of industrial applications due to its refractory nature, extreme hardness and strength, and high electrical and thermal conductivity. It also possesses catalytic activity for many chemical processes such as hydrodeoxygenation, reforming, water-gas shift, and the Fischer-Tropsch reaction. Among the current synthesis methods available to produce β-Mo2C, temperature-programmed reduction yields materials with the highest specific surface areas. The objective of the present work is to perform a detailed investigation of the carburization process and to determine the key intermediate phases that are formed during reduction. To achieve this objective, we performed the carburization process under pulse conditions wherein a small amount of CH4 in each pulse was reacted with a packed bed of MoO2. Our XRD and TEM results demonstrate that the solid-phase transformation from MoO2 to β-Mo2C follows a “plum-pudding” mechanism where Mo metal crystallites are constantly formed as the key intermediate phase throughout the matrix. [ABSTRACT FROM AUTHOR]