Nitrogen-doped carbon xerogels as novel cathode electrocatalysts for oxygen reduction reaction in direct borohydride fuel cells

- Nitrogen-doped carbon xerogels were prepared through a facile synthesis process.
- Nitrogen-doped carbon xerogels prepared through our approach have high catalytic activity and moderate durability for oxygen reduction reaction in alkaline medium.
- The cost-effective nitrogen-doped carbon xerogels have the potential of being readily adaptable for other electrode materials applied to various battery systems.

As a novel catalyst for oxygen reduction reaction (ORR), nitrogen-doped carbon xerogel was prepared via a sol-gel followed by the subsequent pyrolysis in ammonia atmosphere and post-treatment process. The resultant catalysts were characterized by BrunauereEmmetteTeller (BET), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) analysis and electrochemical measurements. The role of metal in the catalyst was studied by comparing catalytic activities of the catalysts with and without post-treatment. Results show that the catalyst with nitrogen doped on the surface possesses an amorphous microstructure. The catalysts with and without post-treatment showed almost the same ORR electrocatalytic activities, which clearly demonstrated the negligible influence of metal removal on ORR performance. The catalyst with post-treatment displayed comparable ORR activity to that of Pt/C in alkaline medium as well as superior stability. A maximum power density of 115 mW cm−2 at 40 °C was achieved on the single cell with the as-prepared catalyst as cathode, demonstrating its application as promising alternative for Pt-based electrocatalysts in direct borohydride fuel cells.