RT Journal Article
T1 Thermochemical Energy Storage Using the Phase Transitions Brownmillerite -2H Perovskite - Cubic Perovskite in the Ca xSr1−xCoO3−δ (x = 0 and 0.5) System
A1 Azcondo, M. Teresa
A1 Orfila, María
A1 Linares, María
A1 Molina, Raul
A1 Marugán, Javier
A1 Amador, Ulises
A1 Boulahya, Khalid
A1 Botas, Juan Ángel
A1 Sanz, Raul
AB The oxides Ca0.5Sr0.5CoO3−δ and SrCoO3−δ, which present perovskite or perovskite-related phases in different temperature domains, have been tested as materials for thermochemical energy storage. The first one, Ca0.5Sr0.5CoO3−δ, experiences a reversible phase transition upon consecutive cycles under an airflow at a maximum operating temperature of 1196 K. Unfortunately, the heat stored in this process, associated with an oxygen loss/gain and a structural phase transition, is very small, hindering its use for thermochemical heat storage. The as-prepared oxide SrCoO3−δ, which displays a brownmillerite structure like the Ca-containing compound, in the first heating step irreversibly segregates some Co3O4 at 823 K to yield a 2H hexagonal perovskite. This phase reversibly transforms at 1073 K into a cubic perovskite. These 2H ⇄ C transitions occur from the 2nd to, at least, 30th cycle. The average absorbed and released heat is ∼104.1 ± 0.06 and ∼68.8 ± 1.8 J/g, respectively, and therefore, SrCoO3−δ presents a high exo/endo ratio. The exergy efficiency is, on average for the 30 cycles performed, as high as 63.9 ± 1.2%. The mechanism of the phase 2H ⇄ C transition of SrCoO3−δ explains the good performance of this material for thermochemical energy storage.
PB American Chemical Society
YR 2021
FD 2021-08-09
LK https://hdl.handle.net/20.500.14352/124417
UL https://hdl.handle.net/20.500.14352/124417
LA eng
NO Azcondo, M. Teresa, et al. «Thermochemical Energy Storage Using the Phase Transitions Brownmillerite -2H Perovskite - Cubic Perovskite in the Ca x Sr 1– x CoO3−δ ( x = 0 and 0.5) System». ACS Applied Energy Materials, vol. 4, n.o 8, agosto de 2021, pp. 7870-81. DOI.org (Crossref), https://doi.org/10.1021/acsaem.1c01235
NO Comunidad de Madrid
NO Ministerio de Ciencia, Innovación y Universidades
NO Agencia Estatal de Investigación
DS Docta Complutense
RD 21 dic 2025