Fe–N Co-doped Porous Carbon Derived from Ionic Liquids as an Efficient Electrocatalyst for the Oxygen Reduction Reaction

Abstract

Development of efficient catalysts with low cost for the oxygen reduction reaction (ORR) plays an important role in the commercialization of fuel cells. Herein, we reported a facile method to synthesize Fe–N co-doped porous carbon (Fe–N/C) by using green media ionic liquids 1-butyl-3-methylimidazolium tetrachloridoferrate ([Bmim]­[FeCl4]) as precursor of C, N, and Fe, and spherical silica as a template through one-step pyrolysis. Electrochemical measurements show that Fe–N/C800 possesses excellent ORR catalytic activity. The onset potential and half-wave potential are 0.964 and 0.821 V, respectively, which is close to those on the commercial Pt/C catalyst. Moreover, it exhibits better methanol tolerance and durability in comparison with the Pt/C catalyst. Good performance of Fe–N/C800 in ORR is attributed to its abundant porous structure, large BET surface area, and the synergism of Fe and N dopants.

Meso‐macroporous Carbons Decorated with Ample Nitrogen Sites as Bifunctional Catalysts in CO2 Catalytic Conversion and Oxygen Reduction Reaction

“…As shown in Figure 8C and S3B, a series of good linear and parallel K‐L plots between J −1 vs ω −0.5 were obtained for both the 3D‐NHPC‐4 and 3D‐NHPC‐2 electrodes at various potentials ranging from 0.25 V to 0.65 V. The electron transfer numbers of electrons transferred per O 2 molecule (n) were calculated from the slope of the K−L plots, which were shown in Figure 8D. Within the range of the electron transfer number from 3.2 to 4 for both 3D‐NHPC‐4 and 3D‐NHPC‐2, the ORR proceeds via a nearly four‐electron reduction mechanism, which are comparable to that of commercial Pt/C [74–76] . The smooth reactant diffusion to active sites and good kinetic process of 3D‐NHPC‐x for ORR was also exhibited by the Tafel carves.…”

Titanium Nitride Hollow Spheres Consisting of TiN Nanosheets and Their Controllable Carbon–Nitrogen Active Sites as Efficient Electrocatalyst for Oxygen Reduction Reaction

“…Pyridinic-N contains a lone electron pair, which can enhance the conductivity and facilitate four-electron process during the reduction reaction . The C 1s spectrum can be deconvoluted into three peaks at 288.7, 286.1, and 284.7 eV (Figure d), corresponding to C–N, C–O and graphitic C, indicating the successful doping of heteroatoms on the carbon lattice . According to areas of the fitted peaks, graphitic C occupies a large proportion in TiN HSs-325, leading to the improvement of high conductivity and limiting current density. , Based on the results from TEM and XPS spectra, we can infer an enhancement caused by alterative electronegativity between the metal titanium and nitrogen atoms, accelerating the charge transfer process in the nitride. , Furthermore, the improved charge transfer could facilitate the formation of active site, which could promote the dissociation and adsorption of oxygen.…”

“…34 The C 1s spectrum can be deconvoluted into three peaks at 288.7, 286.1, and 284.7 eV (Figure 4d), corresponding to C−N, C−O and graphitic C, indicating the successful doping of heteroatoms on the carbon lattice. 35 According to areas of the fitted peaks, graphitic C occupies a large proportion in TiN HSs-325, leading to the improvement of high conductivity and limiting current density. 32,36 Based on the results from TEM and XPS spectra, we can infer an enhancement caused by alterative electronegativity between the metal titanium and nitrogen atoms, accelerating the charge transfer process in the nitride.…”

In Situ Synthesis of Fe−N Co‐doped Porous Carbon Nanospheres by Extended Stöber Method for Oxygen Reduction in Both Alkaline and Acidic Media

“…have become the preferred candidates to replace Pt-based catalysts. [10][11][12] Among of them, Fe-based catalysts had been extensively studied and made breakthrough progress. [13] Many strategies for construction of FeÀ NÀ C materials have been proposed, which were achieved from direct pyrolyzation of organic molecules precursor (e. g., iron phthalocyanine, iron porphyrine complexes).…”