RT Journal Article
T1 Evaluation of cobalt oxides for calcium battery cathode applications
T2 Evaluación las aplicaciones de óxidos de cobalto como cátodo en baterías de calcio
A1 Torres, Arturo
A1 Barde, F.
A1 Arroyo de Dompablo, Elena
AB The identification of potential cathode materials is a requirement for the development of a rechargeable calcium based battery technology. In this work, we use Density Functional Theory (DFT) calculations to explore the electrode characteristics of three ternary calcium cobalt oxides with distinct CoeO dimensionality: 3D-Ca2Co2O5 (brownmillerite type structure), 2D-Ca3Co4O9 (a misfit compound) and 1D-Ca3Co2O6 (K4CdCl6 structural type).For the three compounds calculations predict Co3+/Co4+ voltages in the 3–4 V range, with a volume variation below 8% upon Ca deinsertion. Further Co4+ oxidation is predicted at too high voltages not reachable in practice. The maximum specific capacities are therefore 192 mAh/g (Ca2Co2O5), 165 mAh/g (Ca3Co4O9) and 160 mAh/g (Ca3Co2O6). The potential application of Ca2Co2O5 is discarded based on a large energy barrier for Ca diffusion (1.3 eV). With energy barriers for Ca diffusion of 0.9 eV, the 2D and 1D oxides are appealing as low rate cathode materials. To complete a previous experimental investigation, we have analyzed the reversibility of the Ca deinterclation reaction of 1D-Ca3Co2O6. It is found that a phase transformation takes place upon decalciation driven by the change in the electronic configuration of Co ions (from High Spin-trigonal prismatic Co3+ to octahedral Low Spin-Co4+) and involving the Ca diffusion pathways.
AB Estudio computacional sobre las prestaciones de diversos óxidos de Co como electrodo positivo en baterías recargables de Calcio.
PB Elsevier
SN 0167-2738
YR 2019
FD 2019
LK https://hdl.handle.net/20.500.14352/12310
UL https://hdl.handle.net/20.500.14352/12310
LA eng
NO Unión Europea. Horizonte 2020
NO Universidad de Oviedo
DS Docta Complutense
RD 28 abr 2024