CAS Scientists Discover the Process of Oxygen Activation on Barium-Containing Perovskite Materials

Professor Weishen Yang and Professor Xuefeng Zhu of the Chinese Academy of Sciences’ (CAS) Dalian Institute of Chemical Physics (DICP) have discovered the process of oxygen activation on Barium-containing perovskites.

The scientists found that BaO/BaO₂ nanoparticles precipitated on the surface of Ba-containing materials under elevated-temperature oxygen-rich circumstances had ultra-high oxygen activation activity, elucidating the process of high-temperature oxygen activation and transport on the surface of Ba-containing perovskite oxides.

This research paper was published in the journal Science Advances on April 13^th, 2022.

In 2000, the researchers created an oxygen-permeable membrane material called Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3-δ (BSCF). BSCF has become a typical material for oxygen permeation due to its excellent catalytic activity toward oxygen stimulation and has been extensively used in solid oxide fuel cells, oxygen reduction processes and oxygen evolution activities.

The substance of the BSCF perovskite’s great performance, therefore, is still unknown.

The researchers looked at the oxygen permeation mechanism and discovered that adding Ba to perovskite oxides could speed up the kinetics of the oxygen surface exchange reaction.

Researchers used environmental electron microscopy to identify the precipitation of BaO_x nanoparticles on the surface of BSCF materials in a high-temperature oxygen atmosphere, proving that Ba-containing materials can be prompted or disintegrated into BaO_x, which has high catalytic activity for the oxygen setup process.

Furthermore, researchers discovered that the precipitated BaOx nanoparticles could lower the energy stoppers of oxygen molecule adsorption and detachment in the oxygen reduction and oxygen desorption processes of the oxygen evolution process, thus speeding up the oxygen exchange reaction kinetics at the gas-solid interface, using DFT calculations.

This study provides a scientific basis for the design of oxygen-permeable membranes and electrocatalytic materials.

Weishen Yang, Professor, Dalian Institute of Chemical Physics, Chinese Academy of Sciences

The China Postdoctoral Foundation, the National Natural Science Foundation of China, and the CAS Pilot Project funded the research.

Journal Reference:

Zhu, Y., et al. (2022) Oxygen activation on Ba-containing perovskite materials. Science Advances. doi.org/10.1126/sciadv.abn4072.