REBaCo₂O_5+δ (RE = Pr, Nd, and Gd) as promising oxygen electrodes for intermediate-temperature solid oxide electrolysis cells

Abstract

Double-perovskite REBaCo2O5+δ (RE = Pr, Nd, and Gd) oxides were synthesized and evaluated as oxygen electrodes for intermediate-temperature solid oxide electrolysis cells (IT-SOECs).

Unraveling the promotional role of BaCO3 in the electrode reaction kinetics of an SmBaFe2O5+δ air electrode of reversible solid oxide cells

“…Currently, increasing numbers of outstanding air electrodes with mixed ionic-electronic conductivity have been reported, among which cobaltbased perovskites, such as La 0.6 Sr 0.4 CoO 3−d (LSC), 5 PrBa 0.5 -Sr 0.5 Co 1.5 Fe 0.5 O 5+d , 6,7 and PrBaCo 2 O 5+d (PBC), 8 display favorable performance owing to their superior catalytic activity and ultrahigh conductivity. [9][10][11][12] Unfortunately, the large thermal expansion coefficient (TEC) of these high cobalt-containing oxides (PBC, 28.1 × 10 −6 K −1 from 300 to 900 °C; 11 PBSCF, 25.5 × 10 −6 K −1 from 200 to 900 °C (ref. 13)) severely impairs their thermo-mechanical stability, and the prohibitive cost of cobalt hinders their practical applications.…”

Controlling surface cation segregation in a double perovskite for oxygen anion transport in high temperature energy conversion devices

“…[12][13][14] Among the three, NdBa 1Àx Sr x Co 2 O 5+d is observed to be superior in its electrocatalytic activity in terms of electrical conductivity, area-specific resistance, and thermal expansion coefficient. [14][15][16][17][18] Interestingly, low energy ion scattering (LEIS) experiments by Druce et al 12 have reported cations migrating from the A 0 -site only, while the transition metal does not appear to migrate to the surface. Thus, a specific focus on Ba cations, entailing their partial substitution, may provide a recipe for reducing segregation.…”

High-entropy approach to double perovskite cathode materials for solid oxide fuel cells: Is multicomponent occupancy in (La,Pr,Nd,Sm,Gd)BaCo2O5+δ affecting physicochemical and electrocatalytic properties?

“…Still, the considered materials exhibit some disadvantages, such as relatively high values of the thermal expansion coefficient (TEC), limited chemical stability at the interface with solid electrolytes, vulnerability to CO 2 from the atmosphere, as well as to the previously mentioned Cr-poisoning from the interconnects (Sun et al, 2010). However, it is believed that at least some of those problems can be addressed by proper doping (Liu et al, 2017).…”