A Gd0.2Ce0.8O1.9 impregnated Pr0.4Sr0.6Co0.2Fe0.7Nb0.1O3−δ nanofiber-structured composite anode in solid oxide fuel cells

Abstract

In this study, comparative experiments were conducted based on La_0.8Sr_0.2Ga_0.8Mg_0.2O_3−δ (LSGM) electrolytes, which supported single solid oxide fuel cells (SOFCs) with pure nanofiber-structured Pr_0.4Sr_0.6Co_0.2Fe_0.7Nb_0.1O_3−δ (PSCFN) anodes or Gd_0.2Ce_0.8O_1.9 (GDC) impregnated PSCFN nanofiber-structured composite anodes. The polarization resistance (R_p) values of the pure nanofiber-structured PSCFN anode and the PSCFN–GDC nanofiber-structured composite anode with an optimal mass ratio of 1 : 0.56 were recorded as 1.573 Ω cm² and 0.212 Ω cm² at 850 °C in wet H₂ (97% H₂–3% H₂O), respectively. After impregnating the GDC materials, the maximum power density (P_max) of the single cell with the PSCFN–GDC nanofiber-structured composite anode was found to be about 1.5 times greater than that of the pure nanofiber-structured PSCFN anode at 850 °C in wet H₂. The cell with the PSCFN–GDC nanofiber-structured composite anode presented a significant electrochemical performance in wet H₂. Meanwhile it also showed excellent thermal cycling and long-term stability during the redox and constant-current discharge testing (300 mA cm⁻²) at 850 °C in wet H₂. All of these results indicated that the PSCFN–GDC nanofiber-structured composite anode acted as an efficient and competitive power anode operating in hydrogen fuels.