Atomic‐Level Fe‐N‐C Coupled with Fe₃C‐Fe Nanocomposites in Carbon Matrixes as High‐Efficiency Bifunctional Oxygen Catalysts

Abstract

Technology of HUST for XRD, SEM, TEM, and other measurements. The authors also thanks to the Beamline BL14w1 in SSRF and B12B in NSRL for XAFS and soft XAS measurements. The computational resource was supported by

Ultrafine Fe/Fe3C decorated on Fe-N -C as bifunctional oxygen electrocatalysts for efficient Zn-air batteries

“…2(d), the deconvoluted peaks centered at 706.9 eV and 720.0 eV corresponded to zero-valence Fe, suggesting the existence of metallic iron or carbide, respectively. The peaks located at approximately 710.9 eV and 724.1 eV were attributable to Fe in the Fe-N x configuration [21,27]. These results further confirmed the coexistence of metallic Fe and Fe-N x -C in the Fe/Fe 3 C@Fe-N x -C aerogel, both of which have been established as typical electrocatalytic active sites [28].…”

Metal–Nitrogen–Carbon Catalysts of Specifically Coordinated Configurations toward Typical Electrochemical Redox Reactions

“…Comparatively speaking, facile pyrolysis is still a mainstream strategy to fabricate the M-N-C catalysts. [67,[115][116][117] Single atomic Mn anchored onto the N-doped graphene (Mn-NG) with a MnN 4 configuration was synthesized by calcining precursors of MnCl 2 and graphene oxide under NH 3 atmosphere at different thermal temperatures, followed by removing unpredictable less active Mn-based particles using HNO 3 . [107] In recent years, a number of similar strategies have been developed to modify the pyrolysis synthesis to obtain optimal M-N-C catalysts containing MN 4 sites through the rational design of precursor compositions, architecture, and so on.…”

Pore Modification and Phosphorus Doping Effect on Phosphoric Acid-Activated Fe-N-C for Alkaline Oxygen Reduction Reaction

“…These results were expected to be due to changes in carbon stability due to P doping. The Fe-N-C_PA-0.135 was found to have high activity in the kinetic region despite the low loading amount compared to the previously reported alkaline ORR catalysts (Figure 7c) [53,[68][69][70][71][72][73][74][75][76][77][78]. These results are expected to contribute to solving the water transport problem by electrode thickness [36].…”