Breakthrough in Solid Oxide Fuel Cell ResearchDepartment of Materials Science and Engineering research associate Dr. Yuri Mastrikov and adjunct professor Dr. Maija Kuklja (National Science Foundation [NSF]), in collaboration with Max-Planck Institute researchers Eugene Kotomin and Joachim Maier, have used large scale computer modeling to demonstrate that the vacancy formation energy in (Ba,Sr)(Co, Fe)O3 complex perovskites is much smaller than in other perovskites, which translates into orders of magnitude larger defect concentrations and fast oxygen transport in mixed electronic-ionic conductors for numerous applications. The group recently published its results in Energy & Environmental Science. The work is supported in part by the NSF.
Solid oxide fuel cells (SOFC) are promising devices for generating energy in an environmentally friendly way by a direct conversion of fossil and renewable fuels into electricity and high-quality heat. A major challenge to improving the functionality and implementation of SOFCs is the need to reduce their operating temperatures down to 500–600°C.
In the article, "First-principles modeling of complex perovskite (Ba1-xSrx)(Co1-yFey)O3-δ for solid oxide fuel cell and gas separation membrane applications," the authors describe their search of complex perovskites combining high oxygen vacancy concentration (non-stoichiometry) and high vacancy mobility at moderate temperatures, as well as long-term cubic structure stability against transformation and degradation in polluted atmosphere.
The team has demonstrated that the optimal strategy for developing a new and improved SOFC cathode should be based on the combination of key experimental data on oxygen incorporation into material, and first-principles thermodynamics/kinetics of oxygen reduction and related processes. They have been able to identify the atomistic mechanisms of key reactions for (La,Sr)MnO3 (LSM) with the emphasis on the rate-determining steps. Based on the study, the researchers plan to perform a similar analysis for BSCF and related complex perovskites.
For More Information:
See Yuri A. Mastrikov, Maija M. Kuklja, Eugene A. Kotomin and Joachim Maier, "First-principles modeling of complex perovskite (Ba1-xSrx)(Co1-yFey)O3-δ for solid oxide fuel cell and gas separation membrane applications," Energy Environ. Sci., 2010, Advance Article »
Published August 18, 2010