The Perovskite materials of structure ABO₃ are of great interest because their properties can easily be tailored by partial substitution at the A-site, the B-site, or at both A- and B-sites [1]. The partial substitutions at A- and B-sites create structural defects such as oxygen vacancies, which greatly affect properties like electrical conductivity and thermal stability under oxidizing and reducing conditions [2,3,4]. Recent studies have shown that perovskite-like oxides can serve as possible replacements for Ni-based anode materials [5,6], primarily due to their reported coking resistance which is attributed to their high oxygen storage capacity.

To develop efficient materials possessing high oxygen storage capacity (OSC) for a number of catalytic applications, and also as anodes for SOFC, A series of Strontium doped LaAlO₃ perovskites with formula La_1-XSr_XAlO_3−δ (x=0–0.10) were prepared by precipitation of nitrate precursors followed by calcination at 800 °C in air for 24h. The material properties of the substituted perovskites were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analyses, Raman Spectroscopy, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The doped materials exhibited a single perovskite phase in air up to the Sr doping of 0.4 mole % which was revealed from XRD and Raman analysis. The redoxability and size of the dopants were proposed to play a pivotal role in enhancing the OSC of the as-prepared materials. In this context, the oxidation state of a dopant located at the surface was determined by XPS, Soot oxidation experiments were further performed to examine the relative OSC of the La_1-XSr_XAlO_3−δ based solid solutions and revealed that soot oxidation activities increased till the Sr doping of .05 mole% when compared to undoped LaAlO₃. These results clearly shows that La_1-XSr_XAlO_3−δ materials can be used as anode for SOFC.

References

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