Evaluation of Novel Nanophase Ce_0.8Sr_0.2Fe_0.9Ir_0.1O_3-δ as Cathode Material for Low Temperature SOFC

Abstract

In this study, Ce0.8Sr0.2Fe0.9Ir0.1O3-δ (CSFI) perovskite type material was prepared by sol-gel technique, characterised, and then tested as a cathode material for solid oxide fuel cells operating between 300 – 500 °C. The materials were studied using X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The morphology was examined using scanning electron microscopy and high resolution transmission electron microscopy. Samples showed changes in the overall structure and defect chemistry with an increase in calcination temperature. When tested as cathode materials, the material calcined at 1000 °C had the greatest performance at a test temperature of 500 °C, with a current density of 774.47 mA/cm2, a power density of 483.07 mW/cm2 and an area specific resistance (ASR) of 0.342 Ω/cm2.

Ce0.8Sr0.2CoxFe1‐xO3‐δ (x=0.2, 0.5, 0.8) – A Perovskite‐type Nanocomposite for Application in the Oxygen Evolution Reaction in Alkaline Media

“…It was reported by McCrory et al . [51] that although most electrocatalysts appear to be stable under the operating conditions of stability measurements, at 10 mA cm −2 per geometric area, there is in most cases an increase in potential during the testing period [59, 60]. The increasing shifts in potential observed for the electrocatalysts, during the measurement, may be due to the oxidation of the surface of the electrocatalyst by water‐soluble or other solvated ions, surface changes during measurements, carbon corrosion of the support, and loss in the surface area [61–64].…”

“…At the end of the 10 hrs testing period, the potential for CSCF1 increased by 180 mV, CSCF2 increased by only 181 mV, while CSCF3 increased by 78 mV, which establishes the lowest overpotential and appreciable stability of the CSCF3 (Ce 0.8 Sr 0.2 Co 0.8 Fe 0.2 O 3-δ ) electrocatalyst, for the OER, compared to the other perovskite-type nanocomposites. It was reported by McCrory et al [51] that although most electrocatalysts appear to be stable under the operating conditions of stability measurements, at 10 mA cm À 2 per geometric area, there is in most cases an increase in potential during the testing period [59,60]. The increasing shifts in potential observed for the electrocatalysts, during the measurement, may be due to the oxidation of the surface of the electrocatalyst by water-soluble or other solvated ions, surface changes during measurements, carbon corrosion of the support, and loss in the surface area [61][62][63][64].…”

“…The Rietveld refinement for all nanocomposites are shown in Table 1. Reports describe that changes in the lattice parameters are associated with two factors, i. e. (i) the substitution of the metal ions with smaller or larger ions, and (ii) the changes in the oxygen vacancy concentrations [57][58][59][60].…”

Sol-gel Synthesis of Ce0.8Sr0.2Co1-(x+y)NixFeyO3-δ (x = 0.1, 0.2, and y = 0.2, 0.5, 0.7)—a Nanocomposite-Type Electrocatalyst for the Oxygen Evolution Reaction in Alkaline Media

“…The starting materials employed in the synthesis of CSCNFn [38,39]. These metal salts were all mixed with 20 mL of Milli-Q water and stirred for 10 min, after which it was added dropwise to a 50-mL solution of ethanol and Pluronic F-127 (4.00 g) and stirred employing a magnetic stirrer at 180 rpm, under ambient conditions.…”

Effect of Surfactants on the Physico-Chemical Characteristics of IrO/Ce0.8Sm0.2O2-δNanocomposite for SOFC Application

“…Polarization curves were recorded between 300 -500 °C. The ionic conductivity was calculated thus (15). (2) where, l is the electrolyte thickness, S is electrode area of the electrolyte surface and R is resistance in ohms (cell resistance).The activation energy was calculated using it in the Arrhenius plot (15).…”