Effect of activated graphite nanofibers on electrochemical activities of Pt-Ru nanoparticles for fuel cells

In this work, graphite nanofibers (GNFs) were chemically activated for high specific surface area, small pore diameter, and high oxygen-containing groups with different KOH/GNFs ratios and used as carbon supports of Pt-Ru nanoparticles for fuel cells. As a result, the oxygen functional groups and specific surface area of carbon supports were increased with increasing the ratios of KOH/GNFs up to 4:1, while the average of Pt-Ru nanoparticle size was decreased owing to the improvement of dispersibility of the Pt-Ru/K-GNFs catalysts. The electrochemical activity of the Pt-Ru/K-GNFs catalysts was improved by the larger available active surface area due to the increase of oxygen functional groups and specific surface area. Therefore, it was found that chemical activation using KOH could influence the surface characteristic of carbon supports, resulting in enhanced electrochemical activity of the Pt-Ru/K-GNFs catalysts of fuel cells.