Synthesis of highly ordered three-dimensional nanostructures and the influence of the temperature on their application as solid oxide fuel cells cathodes

The creation of nanostructured materials with three-dimensional periodicity has been identified as a potential interesting field for increasing the overall performance of solid oxide fuel cells (SOFCs). In this work, we have investigated the formation of Pr_0.6Sr_0.4Fe_0.8Co_0.2O₃ nanotubes with different diameter sizes employing polymeric membranes as templates. The samples were characterized by X-ray diffraction and field emission scanning electron microscopy. The polarization resistance of the materials was measured by electrochemical impedance spectroscopy (EIS). A study of the influence of the temperature on the nanostructure has also been carried out, demonstrating that the sintering process affects to the electrochemical performance of the cathode. The study shows that the nanotubes with higher diameter size present a better performance at high temperatures than those with diameter sizes smaller than 100 nm. The ASR (area specific resistance) value of the sample synthesized with a pore diameter size of 0.8 μm is as good as 0.12 Ω cm², allowing it use as cathode in solid oxide fuel cells (SOFCs).