Metal oxides for thermochemical energy storage - From gastriggered isothermal cycling to low-temperature applications with increased O₂ pressure

Author(s)

Christian Knoll, Georg Gravogl, Werner Artner, Elisabeth Eitenberger, Gernot Friedbacher, Andreas Werner, Ronald Miletich, Peter Weinberger, Danny Müller, Michael Harasek

Abstract

Metal oxides providing various, reversibly accessible oxidation states are in the focus as auspicious materials for high-temperature thermochemical energy storage (TCES) materials. Among all principally suitable metal oxides due to equilibrium temperature and, in particular, reaction rate and reversibility, only the couple Co3O4 / CoO and to a smaller extend Mn2O3 / Mn3O4 are considered as suitable candidates. Based on recent studies on isothermal TCES-cycles, the impact of temperature and increased O2-pressure on the reaction rate was investigated by varying the O2-partial pressure in the low-temperature oxidation of the reduced oxide. Whereas Mn3O4 was found to react too slow for a process at lower temperatures, CoO was found suitable. For an increase of the O2 pressure to 6 bar between 500 - 550 °C an attractive oxidation behavior was observed. At 900 °C Co3O4 / CoO could be cycled within 4.5 minutes between both oxidation states by changing the atmosphere from N2 to O2 and vice versa.

Organisation(s)

Department of Mineralogy and Crystallography

External organisation(s)

Technische Universität Wien

No. of pages

10

DOI

https://doi.org/10.18086/swc.2017.14.02

Publication date

2017

Peer reviewed

Yes

Austrian Fields of Science 2012

104003 Inorganic chemistry, 104011 Materials chemistry, 105113 Crystallography

Keywords

ASJC Scopus subject areas

Renewable Energy, Sustainability and the Environment

Portal url

https://ucrisportal.univie.ac.at/en/publications/325c6159-e67f-4f95-8243-fbccbfdbb864