Unveiling the potential of ultra-low load Co on porous carbon-rich SiCN(O) fibre mats towards oxygen electrocatalysis in alkaline medium

• Published in: International journal of hydrogen energy Vol. 88; pp. 956 - 964
• Main Authors: Awin, Eranezhuth Wasan, Miled, Marwan Ben, Comminges, Clément, Habrioux, Aurélien, Bernard, Samuel, Schafföner, Stefan, Motz, Günter
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 28.10.2024; Elsevier
• Subjects: Chemical Sciences
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2024.09.206

The development of efficient and cost-effective catalysts for the oxygen electrocatalysis is crucial for advancing renewable energy technologies, such as fuel cells, electrolyzers and metal-air batteries. Herein, we report the high efficiency of Co nanoclusters generated on porous silicon oxycarbonitride (SiCN(O)) fibre mats towards Oxygen Reduction Reaction (ORR) and Oxygen Evolution Reaction (OER) in alkaline medium. Porous SiCN(O) ceramic fibrous supports were synthesized via electrospinning of a blend of oligosilazane Durazane 1800, polyacrylonitrile and polystyrene followed by an appropriate heat-treatment. Co nanoparticles with a remarkably low mass loading (4 wt%) were immobilized on the SiCN(O) fibres for efficient bifunctional catalytic activity towards OER/ORR. The catalysts exhibited ORR activity (onset potential (E0) of 0.83 V vs. RHE) and excellent stability (80 h) in alkaline medium. Concomitantly, the catalyst required only 1.67 V to drive a current density of 10 mA cm−2 in 1 M KOH for OER. •Co nanoclusters on SiCN(O) fibre mats for ORR/OER in alkaline medium.•Ultra-low mass loading of Co offers high ORR/OER activity with excellent durability.•Nitrogen-doped carbon layers stabilize Co nanocrystals.•Synergistic Co/CoO and N-doped carbon layer promotes the electron transfer.