A hydrogel-assisted GDC chemical diffusion barrier for durable solid oxide fuel cells

Abstract

A novel thin-film coating technique using a gelatin-based GDC precursor solution was developed for dense and smooth 2D layers achieving excellent chemical stability.

Solid oxide fuel cell with a spin-coated yttria stabilized zirconia/gadolinia doped ceria bi-layer electrolyte

“…Moreover, in order to avoid the interaction between YSZ and traditional perovskite cathode materials such as La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3Àd (LSCF), a thin doped ceria interlayer is usually required, which, however, will react with YSZ during the sintering process and form an insulating Ce-Zr solid solution phase. [28][29][30] In this work, YSZ/Ce 0.9 Gd 0.1 O 2Àd (GDC) bi-layer electrolyte is prepared with the slurry spin coating method. The effects of the solvent composition and the YSZ content on the viscosity of the slurry and the morphology of the YSZ membrane are discussed.…”

“…Moreover, in order to avoid the interaction between YSZ and traditional perovskite cathode materials such as La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3− δ (LSCF), a thin doped ceria interlayer is usually required, which, however, will react with YSZ during the sintering process and form an insulating Ce–Zr solid solution phase. 28–30…”

Precursor‐driven facile densification of Gd 0. 1 Ce 0 . 9 O 2− δ interlayer for high‐performance solid oxide fuel cells

“…Solid oxide fuel cells (SOFCs) are promising energy conversion systems because of their high conversion efficiency without any harmful emissions 1‐3 . However, their performance 4 and durability 5‐7 over the long‐term operation, which are directly associated with system costs, remain a challenge for wider commercial applications. Among the various candidates of electrolyte for SOFCs, yttria‐stabilized zirconia (YSZ) is the most commonly used electrolyte material that demonstrates reasonable ionic conductivity and structural robustness 8,9 .…”

“…Thus, a wide range of structural engineering approaches for the GDC interlayer have been reported to maximize the interface characteristics, especially for an intermediate temperature operation 17 . For instance, densification of the GDC interlayer can simultaneously achieve high performance and stability through an enlargement of reaction sites at the cathode layer and complete blocking of cation intermixing at the interface 6,18 . However, fabrication of a sufficiently dense GDC interlayer on the YSZ electrolyte has been challenging because the sintering temperature required for the GDC interlayer is limited to values lower than 1250°C to avoid the formation of insulating secondary phases such as ZrCeO x , whereas full densification of the GDC interlayer requires sintering temperatures to be higher than 1400°C 19 .…”

“…17 For instance, densification of the GDC interlayer can simultaneously achieve high performance and stability through an enlargement of reaction sites at the cathode layer and complete blocking of cation intermixing at the interface. 6,18 However, fabrication of a sufficiently dense GDC interlayer on the YSZ electrolyte has been challenging because the sintering temperature required for the GDC interlayer is limited to values lower than 1250 C to avoid the formation of insulating secondary phases such as ZrCeO x , whereas full densification of the GDC interlayer requires sintering temperatures to be higher than 1400 C. 19 Thus, sintering aids such as Ni, Zn, and Co have often been employed to facilitate densification of the GDC interlayer at lower sintering temperatures. 20 However, these aids can induce undesired phase separation, electronic leakage, and a decrease in ionic conductivity, resulting in deterioration of the electrochemical performance and stability.…”