Hydrophobic effects of nitrogen doped graphene catalysts on oxygen reduction reaction

Abstract

Nitrogen-doped graphene is one of the platinum alternative catalysts for oxygen reduction reaction for polymer electrolyte fuel cells. We have clarified that the pyridine-type nitrogen at the active site undergoes thermal oxygen adsorption and reduction reaction at the same time, and this reaction tends to proceed in a hydrophobic environment. In this study, we synthesized a nitrogen-doped graphene catalyst with enhanced macroscopic hydrophobicity, evaluated the microscopic hydrophobicity near the active point by XPS and acid-base titration, and compared it with the activity.