However, the essence of the good performance of the BSCF perovskite is still unclear.
In this study, the researchers analyzed the oxygen permeation process and found that the addition of Ba into perovskite oxides could accelerate the oxygen surface exchange reaction kinetics.
They identified the precipitation of BaOx nanoparticles on the surface of BSCF materials in a high-temperature oxygen atmosphere by environmental electron microscopy, and proved that Ba-containing materials could be precipitated or decomposed into BaOx have high catalytic activity for the oxygen activation process.
Moreover, combined with DFT calculation, they found that the precipitated BaOx nanoparticles could reduce the energy barriers of oxygen molecule adsorption and dissociation in the oxygen reduction and oxygen desorption of the oxygen evolution process, thus accelerating the oxygen exchange reaction kinetics at the gas-solid interface.
"This study provides a scientific basis for the design of oxygen-permeable membranes and electrocatalytic materials," said Prof. YANG.
The above work was supported by the Pilot Project of CAS, the National Natural Science Foundation of China, and the China Postdoctoral Foundation.