Synthesis and evaluation of (La0.6Sr0.4)(Co0.2Fe0.8)O3 (LSCF)–Y0.08Zr0.92O1.96 (YSZ)–Gd0.1Ce0.9O2−δ (GDC) dual composite SOFC cathodes for high performance and durability

This paper investigates a (La0.6Sr0.4)(Co0.2Fe0.8)O3 (LSCF)–Y0.16Zr0.92O1.96 (YSZ)–Gd0.1Ce0.9O2−δ (GDC) dual composite cathode to achieve better cathodic performance compared to an LSM/GDC–YSZ dual composite cathode developed in previous research. To synthesize the structures of the LSCF/GDC–YSZ and LSCF/YSZ–GDC dual composite cathodes, nano-porous composite cathodes containing LSCF, YSZ, and GDC were prepared by a two-step polymerizable complex (PC) method which prevents the formation of YSZ–GDC solid solution. At 800 °C, the electrode polarization resistance of the LSCF/YSZ–GDC dual composite cathode showed to be significantly lower (0.075 Ω cm2) compared to that of a commercial LSCF–GDC cathode (0.195 Ω cm2), a synthesized LSCF/GDC–YSZ dual composite cathode (0.138 Ω cm2), and an LSM/GDC–YSZ dual composite cathode (0.266 Ω cm2) respectively. Moreover, the Ni–YSZ anode-supported single cell containing the LSCF/YSZ–GDC dual composite cathode achieved a maximum power density of 1.24 W/cm2 and showed excellent durability without degradation under a load of 1.0 A/cm2 over 570 h of operation at 800 °C.

▶ This work is a application research since LSM/GDC–YSZ composite cathode was developed. ▶ The LSCF/YSZ–GDC cathode showed the lowest resistance (0.075 Ω cm2) at 800 °C. ▶ The resistance of the composite cathode remained nearly constant after 50 cycles. ▶ Maximum power densities of 1.24 W/cm2 (800 °C) and 0.5 W/cm2 (650 °C) were obtained. ▶ Durability: 570 h without degradation under a load of 1.0 A/cm2.