Researchers in Lab of Laser Fabrication in Liquids, Institute of Solid State Physics, Hefei Institutes of Physical Science managed to prepare Fe-N-Doped mesoporous carbon with dual active sites for efficient oxygen reduction catalysts. Journal of ACS Applied Materials & Interfaces published their work.

Oxygen reduction reaction, or ORR is always along with slow kinetics, which is the cathode of renewable energy systems. And the effective catalysts are necessary to improve the activity of ORR. To date, Pt-based electrocatalysts are considered as the most efficient electrocatalysts for ORRs.

Unfortunately, the limited reserve and prohibitive cost of Pt-based materials block their large-scale application.

Accordingly, it seems important to develop nonprecious metal catalysts with a low-cost and a comparable performance to replace Pt. Among these, the Fe-N/C catalysts have triggered significant research due to their excellent electrocatalytic activity.

Generally, these Fe-N/C catalysts are synthesized under high temperature, and severe aggregation of products prepared by this method occurs during the pyrolysis process, which results in a decrease of the specific surface area and the accessible part of the active sites, thereby leading to a decline of the electrocatalytic activity.

For these problems, researchers prepared a novel type of Fe-N-C/rGO with high specific surface area and accessible part of active sites. When it was applied to the cathode of renewable energy systems, these catalysts exhibited excellent electrocatalytic performance.

They also found that both the Fe-based nanoparticles and the Fe-Nx active sites in this catalyst are necessary to achieve the good ORR catalytic performance.

This work may provide a new route for fabrication of M-N/C electrocatalysts with a high efficiency for metal-air batteries and fuel cells to replace Pt.

This work was financially supported by the National Basic Research Program of China, the Instrument Developing Project of the Chinese Academy of Science, the National Natural Science Foundation of China, and et al.

The illustration of Fe-N-C/rGO catalysts. (Image by YE Yixing)