Scientific Publication: Reversible Phase Transformations in Novel Ce‐Substituted Perovskite Oxide Composites for Solar Thermochemical Redox Splitting of CO2

ETH Zürich published a scientific publication about SFERA-III in the international research journal, Advanced Energy Materials. The paper is available in open access.

Abstract

Thermochemical splitting of CO2 and H2O via two‐step metal oxide redox cycles offers a promising approach to produce solar fuels. Perovskite‐type oxides with the general formula ABO3 have recently gained attention as an attractive redox material alternative to the state‐of‐the‐art ceria, due to their high structural and thermodynamic tunability. A novel Ce‐substituted lanthanum strontium manganite perovskite‐oxide composite, La3+0.48Sr2+0.52(Ce4+0.06Mn3+0.79)O2.55 (LSC25M75) is introduced, aiming to bridge the gap between ceria and perovskite oxide‐based materials by overcoming their individual thermodynamic constraints. Thermochemical CO2 splitting redox cyclability of LSC25M75 evaluated with a thermogravimetric analyzer and an infrared furnace reactor over 100 consecutive redox cycles demonstrates a twofold higher conversion extent to CO than one of the best Mn‐based perovskite oxides, La0.60Sr0.40MnO3. Based on complementary in situ high temperature neutron, synchrotron X‐ray, and electron diffraction experiments, unprecedented structural and mechanistic insight is obtained into thermochemical perovskite oxide materials. A novel CO2 splitting reaction mechanism is presented, involving reversible temperature induced phase transitions from the n = 1 Ruddlesden–Popper phase (Sr1.10La0.64Ce0.26)MnO3.88 (I4/mmm, K2NiF4‐type) at reduction temperature (1350 °C) to the n = 2 Ruddlesden–Popper phase (Sr2.60La0.22Ce0.18)Mn2O6.6 (I4/mmm, Sr3Ti2O7‐type) at re‐oxidation temperature (1000 °C) after the CO2 splitting step.

References

Title Reversible Phase Transformations in Novel Ce‐Substituted Perovskite Oxide Composites for Solar Thermochemical Redox Splitting of CO2

Authors Naik J. Madhusudhan, Ritter Clemens, Bulfin Brendan, Steinfeld Aldo, Erni Rolf and Patzke Greta

Cite as Naik J. Madhusudhan, Ritter Clemens, Bulfin Brendan, Steinfeld Aldo, Erni Rolf and Patzke Greta. 2021-04-28. “Reversible Phase Transformations in Novel Ce‐Substituted Perovskite Oxide Composites for Solar Thermochemical Redox Splitting of CO2”, Advanced Energy Materials, Volume 11(16), Pages / Article No. 2003532; https://doi.org/10.3929/ethz-b-000473356