One-pot hydrothermal preparation of B and N co-doped graphene aerogels loaded with cobalt oxides for the synergistic enhancement of oxygen reduction electrocatalysis

Release time:2023-10-19 Hits:

Key Words:CARBON NANOTUBES; BIFUNCTIONAL ELECTROCATALYST; 3-DIMENSIONAL NITROGEN; IONIC LIQUID; CATALYST; BORON; PERFORMANCE; NANOPARTICLES; NANOCRYSTALS; NANORIBBONS

Abstract:Developing non-precious metal catalysts with superior activity and stability for the oxygen reduction reaction (ORR) remains challenging for application of full cells. In this work, three-dimensional boron and nitrogen co-doped graphene aerogels loaded with cobalt oxides (3D BNG-Co) catalysts were designed and prepared by a one-pot hydrothermal method. In this 3D nanoarchitecture, CoOx nanoparticles were evenly spread over the BNG surface without aggregation. As a non-precious metal cathode electrocatalyst, the 3D BNG-Co catalyst favors a direct 4e(-) pathway and exhibits excellent activity towards ORR, as well as superior long-term durability. In 0.1 M KOH solution, its onset potential, half-wave potential and limiting current density for the ORR reach -0.02 V (vs. Ag/AgCl), -0.3 V (vs. Ag/AgCl) and 5.6 mA cm(-2), which are comparable to those of commercial 20 wt% PVC catalyst. The good electrochemical activities of the as-fabricated catalyst could be attributed to the 3D network foam, unique electronic structure, and the synergy effect of pyridinic N together with BC3 phases. The present work sheds insights into the effects of diatomic doping of the 3D graphene-based nanostructures in the field of ORR and and can be extended to other catalytic systems. (C) 2020 Elsevier B.V. All rights reserved.

Volume:877

Issue:

Translation or Not:no