Enhancing Oxygen Exchange Activity by Tailoring Perovskite Surfaces.
Yuan ChengAbhinav S RamanJulian PaigeLiang ZhangDanyi SunMavis U ChenAleksandra VojvodicRaymond J GorteJohn M VohsPublished in: The journal of physical chemistry letters (2019)
A detailed understanding of the effects of surface chemical and geometric composition is essential for understanding the electrochemical performance of the perovskite (ABO3) oxides commonly used as electrocatalysts in the cathodes of ceramic fuel cells. Herein, we report how the addition of submonolayer quantities of A- and B-site cations affects the rate of the oxygen reduction reaction (ORR) of Sr-doped LaFeO3 (LSF), LaMnO3 (LSM), and LaCoO3 (LSCo). Density functional theory calculations were performed to determine the stability of different active sites on a collection of surfaces. With LSF and LSM, rates for the ORR are significantly higher on the A-site terminated surface, while surface termination is less important for LSCo. Our findings highlight the importance of tailoring the surface termination of the perovskite to obtain its ultimate ORR performance.
Keyphrases
- density functional theory
- molecular dynamics
- high efficiency
- induced apoptosis
- ionic liquid
- gold nanoparticles
- biofilm formation
- solar cells
- quantum dots
- escherichia coli
- mass spectrometry
- cell death
- oxidative stress
- staphylococcus aureus
- high resolution
- molecular dynamics simulations
- pseudomonas aeruginosa
- endoplasmic reticulum stress
- signaling pathway
- candida albicans
- molecularly imprinted
- pi k akt