Atomically FeN2 moieties dispersed on mesoporous carbon: A new atomic catalyst for efficient oxygen reduction catalysis

ZIF‐8 with Ferrocene Encapsulated: A Promising Precursor to Single‐Atom Fe Embedded Nitrogen‐Doped Carbon as Highly Efficient Catalyst for Oxygen Electroreduction

“…N–C shows a relatively higher bulk N mass ratio of 5.83 wt%, than Fe–N–C (4.2 wt%). However, in XPS Fe 2p signal cannot be detected clearly (Figure S3, Supporting Information), probably due to the low Fe concentration on the catalyst surfaces, in consistent with previous publications, and a relatively low bulk mass ratio of 0.91 detected by ICP‐OES . Fe and N content both samples determined using different characterization methods are summarized in Table S1 (Supporting Information).…”

“…Numerous efforts have been made into controllable synthesis of Fe–N–C catalysts. Shen et al designed a new template casting procedure that could homogeneously disperse large amount of highly active FeN 2 centers on the surface/edges of N‐doped ordered mesoporous carbon . Chen et al reported single iron site confined in graphene catalyst via 4 N atoms, forming flat FeN 4 structure in the matrix of graphene .…”

Modulating the Electronic Structure of Single‐Atom Catalysts on 2D Nanomaterials for Enhanced Electrocatalytic Performance

“…In 0.1 m KOH, the half‐wave potentials of the Fe‐ISAs/CN reached 0.9 V, which is 58 mV more positive than commercial Pt/C. Through DFT calculations, Shen et al suggested the FeN 2 configuration outperforms FeN 4 due to its lower interaction with *O 2 and *OH intermediates and enhanced electron transport (Figure d). Also, they prepared FeN 2 /NOMC catalysts with the N coordination number to be two, as confirmed by EXAFS and 57 Fe Mössbauer spectroscopy.…”

Metallic Porous Iron Nitride and Tantalum Nitride Single Crystals with Enhanced Electrocatalysis Performance

“…

Previous studies show that the metalnitrogen moieties with unsaturated nitrogen coordination numbers possess higher catalytic activities and the reported smallest nitrogen coordination number is confirmed to be ≈2 for Co-N 2 and Fe-N 2 moieties using extended X-ray absorption fine structure spectra analysis. [7][8][9][10] The short length scale of nanostructured catalysts makes it extremely challenging to quantify metal-nitrogen moiety structure and distributions and to correspondingly elucidate the electronic structure features and unusual activity. However, the active metalnitrogen moieties confined at the surface layer of materials that host catalysis reactions still remain unclear.

Building metal-nitrogen moieties with unsaturated nitrogen coordination numbers to enhance material's catalytic activity remains a fundamental challenge.

…”

“…[7][8][9][10] The short length scale of nanostructured catalysts makes it extremely challenging to quantify metal-nitrogen moiety structure and distributions and to correspondingly elucidate the electronic structure features and unusual activity. The state-of-the-art pyrolysis technique of specific precursors is commonly used to construct metal-nitrogen moieties.…”