Promoting Electrocatalytic Activity and Stability via Er_0.4Bi_1.6O_3−δ In Situ Decorated La_0.8Sr_0.2MnO_3−δ Oxygen Electrode in Reversible Solid Oxide Cell

Abstract

Weak electrocatalytic activity of the La 0.8 Sr 0.2 MnO 3−δ (LSM) oxygen electrode at medium and low temperatures leads to decreasing performance both in the solid oxide fuel cell (SOFC) mode and the solid oxide electrolysis cell (SOEC) mode. Herein, we design an Er 0.4 Bi 1.6 O 3−δ (ESB) functionalized La 0.8 Sr 0.2 MnO 3−δ (labeled as LSM/ESB) oxygen electrode via a one-step co-synthesis modified Pechini method. The unique LSM/ESB with polarization resistance of only 0.029 Ω•cm 2 at 750 °C enables a highly enhanced rate of oxygen reduction and evolution reaction. The single cell with the LSM/ESB electrode achieves a maximum power density of 1.747 W cm −2 at 750 °C, 2.6 times higher than that of the mechanically mixed LSM−ESB electrode (0.667 W cm −2 ). In the SOEC mode, it also shows the improved performance of the LSM/ESB electrode. Furthermore, the cell exhibits admirable durability of 90 h in the fuel cell mode and excellent reversibility. The better performance can be concluded as a better surface-active state and a tighter connection between the LSM and ESB particles of LSM/ESB via a co-synthesis process. This work proposes a novel strategy to advance the application of the one-step modified Pechini technology for an efficient and stable oxygen electrode.

Electrochemical Performance of Pr0.4Sr0.5CoxFe0.9–xMo0.1O3−δ Oxides in a Reversible SOFC/SOEC System

“…Four peaks are obtained, representing P 1 , P 2 , P 3 , and P 4 , respectively, corresponding to the low-frequency region (LF), medium-frequency region (IF), and high-frequency region (HF) . Based on the Adler–Lane–Steele model, the LF region corresponding to the P 1 peak reflects the gas diffusion process, the IF region corresponding to P 2 and P 3 peaks reflects the ion surface exchange process, and the HF region corresponding to the P 4 peak reflects the interface charge transfer process . It can be seen that different materials lead to different peaks in each region, and the place with the largest peak difference occurs in IF and HF regions, suggesting that the interface charge transfer process and ion surface exchange process are the main factors affecting the catalytic activity of the material.…”

Promoting High-Temperature Oxygen Evolution Reaction via Infiltration of PrCoO3−δ Nanoparticles

“…The latter two can be collectively labeled as the adsorbed oxygen (O ads. ). ,− It is evident that the fraction of O ads. increases for both PBCFT-GDC and 6% PC/PBCFT-GDC anodes after a constant current density of 350 μA cm –2 is applied to the SOECs, due to the lattice oxygen spillover from TPBs onto the anode surface.…”

A mini review of the recent progress of electrode materials for low-temperature solid oxide fuel cells

“…Through the distribution of relaxation time (DRT) analysis, the heterogeneous coherent interface between PrBaCo 2 O 5+d /Gd 0.1 Ce 1.9 O 2Àd composites prepared in a one-pot step was proven to enhance the oxygen exchange kinetics and boost the charge transfer subreaction. 88 Liu et al 89 compared the intrinsic properties and electrochemical performance of the one-pot co-synthesis LSM/ ESB with those of the mechanically mixed LSM-ESB electrode.…”

“…Through the distribution of relaxation time (DRT) analysis, the heterogeneous coherent interface between PrBaCo 2 O 5+ δ /Gd 0.1 Ce 1.9 O 2− δ composites prepared in a one-pot step was proven to enhance the oxygen exchange kinetics and boost the charge transfer sub-reaction. 88 Liu et al 89 compared the intrinsic properties and electrochemical performance of the one-pot co-synthesis LSM/ESB with those of the mechanically mixed LSM-ESB electrode. It showed that co-synthesized LSM/ESB electrode had a larger surface area (21.18 m 2 g −1 vs. 3.75 m 2 g −1 ), higher electronic conductivity (665 S cm −1 vs. 277 S cm −1 ), and tighter connection between LSM and ESB particles compared with the mechanically mixed LSM-ESB electrode, which resulted in the improved electrochemical performance (1.747 W cm −2 vs. 0.667 W cm −2 at 750 °C).…”