Porous Doped Carbon Nanocomposites As Electrocatalysts For Oxygen Reduction Reaction

Oxygen reduction reaction（ORR）electrocatalyst can improve the cathodic reaction rate of fuel cells,thereinto,Pt-based catalysts have the highest ORR catalytic activity,however,the development of Pt-based catalysts has encountered difficulties due to a series of shortcomings such as insufficient resources and high cost.To seek materials that can replace noble metal catalysts is the key to the research of ORR electrocatalyst.The main results in this dissertation are as follows:1.Porous Fe,N-doped graphene carbon nanosheet composite as electrocatalyst for alkaline ORR:Fe,N-PCN sample was synthesized by mixing reaction,high temperature carbonization and etching using GO as template and DA,APTES and Fe Cl₃ as precursors.Fe,N-PCN has a limit current density of-4.8 m A cm^-2 and a half-wave potential of 0.87 V,which are much close to those of Pt/C.2.Porous Fe,N-doped carbon nanotube composite as an electrocatalyst for alkaline ORR:Fe/PNCNT sample were synthesized using Ox-CNT as template and DA,APTES and Fe Cl₃ as precursors.The limit current density of the sample Fe/PNCNT is-4.82 m A cm^-2 and the half-wave potential is 0.88 V.3.Porous Fe,N-doped carbon nanosphere composite as electrocatalysts for alkaline ORR:Fe/PNC were synthesized by using DA,APTES and Fe Cl₃ as precursors and 15 nm Si O₂ sphere as template.The limit current density and half-wave potential of Fe/PNCNT is-4.82 m A cm^-2 and 0.88 V,respectively.Through hydrofluoric acid etching,Si O₂ produces a large number of porous structures,which increases the active area and enhances the ORR activity.