The manufacture of fuel cells that can operate directly on various hydrocarbon fuels, without the need for reforming, has the potential of greatly speeding the application of fuel cells for transportation and distributed-power applications. This paper will briefly review the literature in this area and describe recent developments in solidoxide fuel cells (SOFCs) that demonstrate that direct-oxidation fuel cells are possible with Cu-based anodes. A new method for synthesizing thin-electrolyte, anode-supported cells is described that is based on tape casting with graphite pore formers (see Figure), followed by impregnation with aqueous solutions of Cu(NO 3 ) 2 and Ce(NO 3 ) 3 . The performance of model SOFCs for direct conversion of n-butane and methane is shown. Finally, future developments that are needed for this technology to be commercialized are discussed.

With the need for more stable and active metal catalysts for dry reforming of methane, in situ grown nanoparticles using exsolution are a promising approach. However, in conventional exsolution, most nanoparticles remain underneath the surface because of the sluggish diffusion rate of cations. Here, we report the atomic layer deposition (ALD)–combined topotactic exsolution on La0.6Sr0.2Ti0.85Ni0.15O3-δ toward developing active and durable catalysts. The uniform and quantitatively controlled layer of Fe via ALD facilitates the topotactic exsolution, increasing finely dispersed nanoparticles. The introduction of Fe2O3 yields the formation of Ni-Fe alloy owing to the spontaneous alloy formation energy of −0.43 eV, leading to an enhancement of the catalytic activity for dry methane reforming with a prolonged stability of 410 hours. Overall, the abundant alloy nanocatalysts via ALD mark an important step forward in the evolution of exsolution and its application to the field of energy utilization.

Exsolution is a novel technology for attaching metal catalyst particles onto ceramic anodes in the solid oxide fuel cells (SOFCs). The exsolved metal particles in the anode exhibit unique properties for reaction and have demonstrated remarkable stabilities under conditions that normally lead to coking. Despite extensive investigations, the underlying principles behind exsolution are still under investigation. In this review, the present status of exsolution materials for SOFC applications is reported, including a description of the fundamental concepts behind metal incorporation in oxide lattices, a listing of proposed mechanisms and thermodynamics of the exsolution process and a discussion on the catalytic properties of the resulting materials. Prospects and opportunities to use materials produced by exsolution for SOFC are discussed.

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Recent developments in solid-oxide fuel cells (SOFC) that electrochemically oxidize hydrocarbon fuels to produce electrical power without first reforming them to H 2 are described. First, the operating principles of SOFCs are reviewed, along with a description of state-of-the-art SOFC designs. This is followed by a discussion of the concepts and procedures used in the synthesis of direct-oxidation fuel cells with anodes based on composites of Cu, ceria, and yttria-stabilized zirconia. The discussion focuses on how heterogeneous catalysis has an important role to play in the development of SOFCs that directly oxidize hydrocarbon fuels. AbstractRecent developments in solid-oxide fuel cells (SOFC) that electrochemically oxidize hydrocarbon fuels to produce electrical power without first reforming them to H 2 are described.First, the operating principles of SOFCs are reviewed, along with a description of state-of-the-art SOFC designs. This is followed by a discussion of the concepts and procedures used in the synthesis of direct-oxidation fuel cells with anodes based on composites of Cu, ceria, and yttriastabilized zirconia. The discussion focuses on how heterogeneous catalysis has an important role to play in the development of SOFCs that directly oxidize hydrocarbon fuels.