Abstract
Two-step thermochemical cycle for CO2 splitting has been studied using cerium oxide (CeO2-δ) as a redox material. Since oxygen release capacity of CeO2-δ increases by doping ZrO2, a lot of studies have been conducted on CeO2-ZrO2 solid solutions as state of the art redox materials for this cycle. In this study, further doping of Sc3+ into CeO2-ZrO2 solid solution was attempted with an expectation to increase amount of available oxygen vacancies which could improve redox kinetics. Scandium was chosen since the ionic radius is close to Zr4+and oxygen vacancy is introduced by the aliovalent doping. Oxygen nonstoichiometry of Ce0.8Zr0.15Sc0.05O2-δ was investigated by a coulometric titration method and chemical diffusion coefficient and surface reaction rate constant by an electrical conductivity relaxation method. Oxygen vacancy formation of Ce0.8Zr0.15Sc0.05O2-δ upon reduction was similar to that of Ce0.8Zr0.2O2-δ, while chemical diffusion coefficient in a high oxygen partial pressure region became larger by introducing Sc3+. Those were discussed in correlation with the reaction kinetics in the thermochemical cycle.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
