Materials for reversible solid oxide cells

Investigation of the Long‐term Stability of Solid Oxide Electrolysis Stacks under Pressurized Conditions in Exothermic Steam and Co‐electrolysis Mode

“…Furthermore, the electrical contact between the GDC particles within the porous electrode could become worse, due to the loss of highly conductive Ni material and relatedly formed cavities. Hence, the predominant electrochemical reaction zone moves to the outer part of the electrode layer [30,63]. Additionally, the loss of Ni leads to an increased polarization resistance of the fuel electrode which is in good agreement with the experimental results shown in the EIS spectra of Figure 8.…”

“…Due to the increasing voltage, the characteristic cell temperature increases by 3.13 K kh -1 . The authors want to point out that contrary to the authors' previous studies and many other publications the degradation rates will not be given in percentages, since this specification is highly dependent on the operating voltage and can lead to wrong interpretation of the degradation [5,14,[16][17][18][19][20][27][28][29][30][31]. The indication of the shift in voltage and ASR during the operating time leads to much better comparability of experimental studies.…”

“…Experiments in atmospheric conditions with a similar ESC single cell configuration have already shown a voltage shift of approximately 7 mV kh -1 at current densities between -0.5 and -0.9 A cm -2 [13,41] Both the steam content (75%) and the reactant conversion (51%) were lower than the ones of the presented study whereas the temperature was slightly higher (~850°C). The electrolyte material of the cell was 6Sc1CeSZ which has a generally higher conductivity than the 3YSZ material used in the stacks of the current study, hence higher current densities could be achieved while operating in long-term endothermic mode [30]. The same ESC architecture with a 3YSZ electrolyte on single cell level was used in another long-term study at atmospheric conditions [15].…”

Electrochemical performance of La2NiO4+δ-Ce0.55La0.45O2-δ as a promising bifunctional oxygen electrode for reversible solid oxide cells

“…However, the polarization loss of the bifunctional oxygen electrode is the key factor limiting the overall performance of RSOCs, which mainly dominated by its electrocatalytic activities for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) [5,6]. Considerable efforts have been devoted to reduce the polarization loss of the oxygen electrode by exploring novel materials [7,8]. However, oxygen electrode materials with satisfactory electrochemical performances for RSOCs are sill elusive.…”

Electrochemical p erformance of La2NiO4+δ-Ce0.55La0.45O2-δ as a promising bifunctional oxygen electrode for reversible solid oxide cells

“…However, the polarization loss of the bifunctional oxygen electrode is the key factor limiting the overall performance of RSOCs, which mainly dominated by its electrocatalytic activities for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) [5,6] . Considerable efforts have been devoted to reduce the polarization loss of the oxygen electrode by exploring novel materials [7,8] . However, oxygen electrode materials with satisfactory electrochemical performances for RSOCs are sill elusive.…”