Subnano Amorphous Fe-Based Clusters with High Mass Activity for Efficient Electrocatalytic Oxygen Reduction Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Cost-effective and efficient electrocatalysts are crucial for sustainable fuel cells.
• Oxygen reduction reaction (ORR) catalysts are key components in fuel cell technology.

Purpose of the Study:

• To develop a novel subnano amorphous transition-metal cluster electrocatalyst for ORR.
• To investigate the performance and mechanism of Fe subnano-cluster/3D-C for ORR.

Main Methods:

• Synthesis of Fe subnano-cluster/3D-C using an "amino-induced spatial confinement" strategy.
• Electrocatalytic performance evaluation for ORR.
• Atomic characterizations and theoretical calculations to elucidate the catalytic mechanism.

Main Results:

• The Fe subnano-cluster/3D-C catalyst exhibited outstanding ORR performance.
• Achieved a high mass activity of ~8600 A g_Fe^-1 at a half-wave potential of 0.92 V.
• Demonstrated ~10 times higher performance than the benchmarking Pt/C electrocatalyst.

Conclusions:

• The developed Fe subnano-cluster/3D-C is a promising ORR electrocatalyst.
• Robust surface-covalent Fe-N bonds and synergistic Fe^2+/0 species contribute to high activity.
• This work offers a new avenue for designing efficient and cost-effective ORR electrocatalysts.