One-pot impregnation to construct nanoparticles loaded scaffold cathode with enhanced oxygen reduction performance for LT-SOFCs

Constructing nanoparticles loaded scaffold cathode is an effective strategy to reduce the polarization resistance of cathode for Low-temperature Solid Oxide Fuel Cells (LT-SOFCs). Here, self-assembled Ce0.9Gd0.1O2-δ (GDC) microrods were prepared by liquid precipitation method, and used for constructing cathode scaffold. There are interconnected micron level pores with the porosity up to 81.03% in the cathode scaffold, benefitting for directly impregnating solution and even nanoparticles, and gaseous oxygen transport under cell testing. The electrochemical impedance spectra and corresponding distribution of relaxation times results reveal that the porous and continuous distribution of La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) nanoparticles loaded on GDC scaffold via one-pot impregnation could significantly provide the rapid gas diffusion, abundant adsorption sites, enough reactive sites and unobstructed ionic/electronic conduction to obtain the excellent oxygen reduction performance under lower operating temperatures. The cathode with the GDC scaffold impregnated the LSCF nanoparticles only one time exhibits the total polarization resistance of 0.293 Ω·cm2, significantly less than 0.615 Ω·cm2 of the traditional cathode at 600 °C. The porous nanoparticles loaded scaffold cathode with simple preparation process and excellent oxygen reduction performance is expected to promote the further development of LT-SOFCs.