Journal Article

Sintering Aid Strategy for Promoting Oxygen Reduction Reaction on High-Performance Double-Layer LaNisub.0.6Fesub.0.4Osub.3–δ Composite Electrode for Devices Based on Solid-State Membranes

Osinkin, Denis, Bogdanovich, Nina

2023

Overview

Strontium and cobalt-free LaNi[sub.0.6]Fe[sub.0.4]O[sub.3–δ] is considered one of the most promising electrodes for solid-state electrochemical devices. LaNi[sub.0.6]Fe[sub.0.4]O[sub.3–δ] has high electrical conductivity, a suitable thermal expansion coefficient, satisfactory tolerance to chromium poisoning, and chemical compatibility with zirconia-based electrolytes. The disadvantage of LaNi[sub.0.6]Fe[sub.0.4]O[sub.3–δ] is its low oxygen-ion conductivity. In order to increase the oxygen-ion conductivity, a complex oxide based on a doped ceria is added to the LaNi[sub.0.6]Fe[sub.0.4]O[sub.3–δ]. However, this leads to a decrease in the conductivity of the electrode. In this case, a two-layer electrode with a functional composite layer and a collector layer with the addition of sintering additives should be used. In this study, the effect of sintering additives (Bi[sub.0.75]Y[sub.0.25]O[sub.2–δ] and CuO) in the collector layer on the performance of LaNi[sub.0.6]Fe[sub.0.4]O[sub.3–δ]-based highly active electrodes in contact with the most common solid-state membranes (Zr[sub.0.84]Sc[sub.0.16]O[sub.2–δ], Ce[sub.0.8]Sm[sub.0.2]O[sub.2–δ], La[sub.0.85]Sr[sub.0.15]Ga[sub.0.85]Mg[sub.0.15]O[sub.3–δ], La[sub.10](SiO[sub.4])[sub.6]O[sub.3–δ], and BaCe[sub.0.89]Gd[sub.0.1]Cu[sub.0.01]O[sub.3–δ]) was investigated. It was shown that LaNi[sub.0.6]Fe[sub.0.4]O[sub.3–δ] has good chemical compatibility with the abovementioned membranes. The best electrochemical activity (polarization resistance about 0.02 Ohm cm[sup.2] at 800 °C) was obtained for the electrode with 5 wt.% Bi[sub.0.75]Y[sub.0.25]O[sub.1.5] and 2 wt.% CuO in the collector layer.

• Publisher: MDPI AG
• Subject: Sintering