Three-dimensional N,B-doped graphene aerogel as a synergistically enhanced metal-free catalyst for the oxygen reduction reaction

Abstract

Here, a novel N,B-doped graphene aerogel, abbreviated as N,B-GA, was obtained via a two-step approach and served as a metal-free catalyst for the oxygen reduction reaction (ORR). This two-step method involved a hydrothermal reaction and a pyrolysis procedure, guaranteeing the efficient insertion of the heteroatoms. The resulting three-dimensional (3D) N,B-GA obtained at pyrolysis temperature of 1000 °C exhibited outstanding catalytic activity for the oxygen reduction reaction (ORR), comparable to that of Pt/C. In addition, the catalytic activity of this 3D N,B-GA was obviously better than that of the nitrogen-doped graphene aerogel (N-GA) and boron-doped graphene aerogel (B-GA) in terms of the onset potential, half-wave potential and diffusion limiting current density. The superior catalytic reactivity arises from the synergistic coupling of the B and N dopants within the graphene domains.

Cobalt Sulfide Nanowires Core Encapsulated by a N, S Codoped Graphitic Carbon Shell for Efficient Oxygen Reduction Reaction

“…As previously reported in the literature, the nitrogen‐doped carbon spheres derived from PDA carbonization have a relatively small BET surface area . Meanwhile, the apparent hysteresis loop in the high pressure ( P / P 0 = 0.9–1.0) and pore distribution curve presented in Figure S8A in the Supporting Information demonstrate the macropore‐dominated structure for Co NPs/NC, which contributes less for the improvement of ORR activity . On the contrary, the other samples prepared by Co(CO 3 ) 0.5 (OH) 0.11 H 2 O NWs show mesoporous architectures observed from the pore size distribution curves, which facilitate mass transport, accelerate electron transfer, expose active sites, and further improve ORR electrocatalytic performance.…”

Influence of nitrogen precursors on the structure, composition, and oxygen reduction reaction performance of dual heteroatom doped carbon nanohorns

“…On the N 1s XPS spectrums of NCNHs ( Fig.2A), four kinds of N species including pyridinic N (~398.7 eV, named N1), pyrrolic N (~399.9 eV, named N2), quaternary N (~401.4 eV, named N3), and N-oxides of pyridinic N (~402.8 eV, named N4) can be discriminated. 16,18,28 Herein, two kinds of dualdoped carbon nanohorns were produced. Moreover, for NCNH-a, 50.2% N atoms are in the form of pyridinic N, while 41.9% of the N in NCNH-m is present in the form of pyrrolic N. Thus, despite the little large pore size and much pyridinic N in NCNH-a, and a bit high specific surface area and pyrrolic N in NCNH-m, their structures and compositions are similar to each other in general.…”

Using Multifunctional Polymeric Soft Template for Synthesizing Nitrogen and Phosphorus Co–Doped Mesoporous Carbon Frameworks Electrocatalysts for Oxygen Reduction Reaction

“…Heteroatom‐doped carbon materials possess plentiful free‐moving π electrons, ultra‐high electric conductivity and superior stability. To introduce heteroatom (nitrogen,, phosphorous,, sulphur,, and boron,) into carbon skeleton can improve electron distribution; change the degree of defects and optimizing the property of surface, which further enhance the ORR performance . Among the metal‐free heteroatom‐doped carbon materials, N‐doping has been given much attention.…”