Waste Tire Derived Carbon Support for Non-Platinum-Group Metal Catalyst Materials for Oxygen Reduction Reaction in Alkaline Medium

Abstract

A porous carbon material was synthesized using waste tire granules via pyrolysis. Six non-platinum-group metal catalyst materials were synthesized based on this carbon material, Fe(NO3)3 · 9H2O, and either dicyandiamide or guanidine carbonate as the nitrogen source. Synthesis parameters such as pyrolysis temperature, precursor mass ratios, and acid washing time were varied for each material. All catalysts were characterized physically using HR-SEM, SEM-EDX, and N2 sorption analyses as well as electrochemically using the rotating disk electrode method in 0.1 M KOH. The materials were rich in nanofibers, and exhibited moderate porosity and specific surface area (S BET = 77-194 m2 g-1). By modifying the synthesis parameters of the materials, the electrochemical properties were successfully improved, achieving E onset = 0.92 V vs RHE and E 1/2 = 0.82 V vs RHE (Fe-guan III 900). The number of transferred electrons in the ORR was n = 4 for the more active materials.