Preparation and oxygen reduction electroactivity of metal nanoparticles loaded on sheet-like carbon composites

Herein, Co/C-N, Fe/C-N, and Fe-Co/C-N nanocomposites were obtained by the self-template method, and high. temperature pyrolysis of the mixture composed of dicyandiamide, sucrose, and cobalt (ferric) phthalocyanine as nitrogen, carbon, and metal sources respectively. Then a small amount of platinum was deposited on the Co/C-N with better oxygen reduction reaction (ORR) electroactivity by thermal reduction to obtain carbon nanosheet - supported Co-Pt nanoparticles (Co-Pt/C-N). The catalysts were well characterized and tested for ORR. The Co/C-N catalyst displayed the onset potential (E-onset) and half-wave potential (E-1/2) of ORR closed to the Pt/C in an alkaline solution, and it even presented the more positive onset potential and half. wave potential in a neutral solution. For Co-Pt/C-N, its ORR electroactivity in an acidic solution was greatly enhanced compared with the Co/C-N and was comparable to the Pt/C. The excellent ORR electroactivity of the samples is mainly attributed to the 3D structure formed by the carbon nanosheets, uniform distribution of the metal nanoparticles, and abundant pyridine N.