Electrochemical Characteristics and Gas Composition Generated by La_0.8Sr_0.2Cr_0.5Mn_0.5O_3–δCathode at Electrolysis and Co-Electrolysis Modes

Abstract

Ceramic materials with perovskite structure have recently attracted attention as possible redox stable, sulfur- and carbon tolerant cathode materials for solid oxide electrolysis cells. In this study ceramic SOE single cell was fabricated using impregnation method. La0.8Sr0.2Cr0.5Mn0.5O3–δ-Zr0.94Sc0.06O2–δ cathode was activated with CeO2 and Pd nanoparticles and investigated as potential solid oxide co-electrolysis cell cathode at various working temperatures, cell potentials and inlet gas compositions. Based on the electrochemical measurements data the single cell performed the same in co-electrolysis and water electrolysis modes having total polarization resistance 0.52 Ω cm2 (at 750°C at 1.3 V). Analysis of gas chromatography data shows that the ratio between produced H2 and CO gases decreased with increase of temperature, from 10.5 to 0.76 at 650°C and 800°C, respectively. Also the H2/CO ratio decreased with steam content in inlet gas.

An Up-scalable, Infiltration-Based Approach for Improving the Durability of Ni/YSZ Electrodes for Solid Oxide Cells

“…Several different microstructural deteriorations have been reported as contributing to the electrochemical performance degradation, including surface poisoning by impurities, Ni coarsening and migration, destruction of the Ni-YSZ interface, and even formation of ZrO2 nanoparticles on the Ni surface due to the reduction/re-oxidation of YSZ. [3][4][5][6][7][8][9][10][11][12][13][14] Though mixed ionic-electronic conducting (MIEC) oxides, such as LaxSr1-xCr0.5Mn0.5O3-δ, [15][16][17] La0.2Sr0.8TiO3+δ, 18 La0.4Sr0.4Ni0.06Ti0.94O3-δ, 19 La0.43Ca0.37Ni0.06Ti0.94O3-δ, 20 and Sr2Fe1.5Mo0.5O6-δ, 21,22 have been explored as alternative fuel electrodes, the catalytic activity and electrical conductivity of these MIEC electrodes have not reached the levels observed for the Ni/YSZ electrodes. Accordingly, it is important to enhance the durability of Ni/YSZ electrodes.…”

Influence of Electrolyte Scaffold Microstructure and Loading of MIEC Material on the Electrochemical Performance of RSOC Fuel Electrode

“…The linear shape of cyclic voltammograms indicates that ohmic drop limitations in single cells are determining current values if SFM loading is only 10% (Figure a). If SFM loading has been increased up to 20 and 30% (Figures b and c), then the current densities increased significantly and the shape of cyclic voltammogramm at electrolysis mode changed to be more like has been reported in the case of diffusion limited systems with weakly expressed current plateau . Thus, the increase of SFM loading improves the electron‐conductive MIEC network activity in porous electrode, which leads to the decrease of ohmic drop limitations, but on the other hand it also decreases the porosity necessary for quick transport of reactants and products of the electrochemical reaction.…”

Study of Electrochemical and Crystallographic Changes During Initial Stabilization of La0.75Sr0.25Cr0.5Mn0.3Ni0.2O3−δ Reversible Solid Oxide Cell Electrode

“…ScCeSZ wafers were created by the lamination of four green tapes together (porous-dense-dense-dense) using isostatic compression (isostatic laminating system ILS 46, Keko Equipment), which was followed by sintering at 1,400°C for 5 h. The thickness of the dense electrolyte layer was 220 μm, and the geometric surface area of the porous electrode was 0.87 cm 2 . A more detailed description can be found in our previous study [33].…”