Synthesis and powder characterization of NiSmCeCu catalysts for the anode reforming layer of solid oxide fuel cells

Abstract

Solid oxide fuel cells (SOFCs), a type of fuel cell that can operate on several fuels without requiring an external reformer, are among the most promising fuel cell types. However, the effects of hydrocarbon fuels, associated with carbon deposition and poisoning, hinder the performance of solid oxide fuel cells (SOFCs). Conventional anodes of composite nickel-yttria-stabilized zirconia (Ni-YSZ) are not resistant to both, leading to long-term deterioration. One of the strategies to mitigate the impact of carbon deposition and poisoning is to introduce a catalyst reforming layer. The performance of the catalyst reforming layer is associated with the raw materials produced through synthesis methods. Thus, this paper studies three wet synthesis routes for producing powders of catalyst materials, namely sol-gel (SG), solution combustion synthesis (SCS), and co-precipitation (CP). An X-ray diffraction (XRD) analysis reveals that all the synthesis methods successfully formed the NiSmCeCu-based catalysts with different crystallite sizes. The sol-gel method exhibited the smallest crystallite size, approximately 32.7 nm, followed by solution combustion at 39.4 nm and co-precipitation at 49.4 nm. The pore size and Brunauer-Emmett-Teller (BET) surface area of the catalyst from SG also exhibit higher values than those of other methods. The micrograph of the catalyst from SG and SCS reveals a highly porous structure with numerous small cavities. These findings suggest that the SG method offers significant advantages in producing catalyst material with desirable structural and surface characteristics for SOFC application.