Screening of Catalytic Activity
The prediction of catalytic activity of different materials is important for optimizing chemical processes and reliable control of pollutions. Theoretical screening of the catalytic activity allows the researcher to safe resources and time for process development. An example of screening catalytic activity is given below for mixed electron-ion-conductor systems.
Catalytic Activity of Mixed Ionic-Electronic Conductors
Mixed ionic-electronic conductors La1-xSrxCoyFe1-yO3 (LSCF) were considered as possible candidates for Pt replacement in fuel cell cathodes. Researchers at Kintech Labs investigated surface exchange processes on La1-xSrxCoO3 (LSC) and La1-xSrxFeO3 (LSF) cathodes using the first-principles approach. The main attention was paid to oxygen adsorption and dissociation on the surface and the recombination of oxygen vacancies with adsorbed oxygen atoms near the surface. An example of the reaction of oxygen molecule dissociation on the LSC(110) surface is shown in figure below:
Reaction pathways for oxygen dissociation on the LSC and LSF (110) surfaces calculated by quantum-chemistry methods are shown below. It can be seen that the energy barrier for O2 is about 0.8 eV on LSC and 0.4 eV on LSF.
