Layered perovskite-like Pr2-xErxNiO4 as an improved cathode for intermediate-temperature solid oxide fuel cells

The successful commercialisation of intermediate-temperature solid oxide fuel cells (IT-SOFCs) hinges on the development of cathode materials exhibiting outstanding activity. The present study utilized a sol-gel combustion technique to efficiently synthesize Pr2-xErxNiO4 (x = 0, 0.075, 0.100, 0.125, and 0.150) cathode powders. The effect of Er3+ doping on the phase structure, thermal behaviour, and electrochemical properties was examined, and the performance of single-cell NiO-GDC|GDC|Pr2-xErxNiO4 was tested. X-ray diffraction analysis revealed that the Pr2-xErxNiO4 formed a structure similar to K2NiF4 and exhibited chemical compatibility with the GDC electrolyte. FT-IR testing verified the entry of Er3+ into the Pr site. XPS investigation showed that the introduction of Er3+ resulted in augmented oxygen content on the surface of the Pr2NiO4. The Pr1.9Er0.1NiO4 cathode material demonstrated a conductivity of 128.85 S cm-1 at 750 degrees C and a resistance (Rp) as low as 0.035 Omega cm2. Additionally, the peak power density of the NiO-GDC|GDC|Pr1.9Er0.1NiO4 single-cell at 750 degrees C reached 0.639 W cm-2. The findings suggest that Pr2-xErxNiO4 shows potential as a promising improved cathode for ITSOFCs.