Crystalline Dual-Porous Covalent Triazine Frameworks as a New Platform for Efficient Electrocatalysis.
Angew Chem Int Ed Engl
; 63(6): e202317664, 2024 Feb 05.
Article
em En
| MEDLINE
| ID: mdl-38131249
ABSTRACT
Crystalline covalent triazine frameworks (CTFs) have gained considerable interest in energy and catalysis owing to their well-defined nitrogen-rich π-conjugated porosity and superior physicochemical properties, however, suffer from very limited molecular structures. Herein we report a novel solvent-free FeCl3 -catalyzed polymerization of 2, 6-pyridinedicarbonitrile (DCP) to achieve the first synthesis of crystalline, dual-porous, pyridine-based CTF (Fe-CTF). The FeCl3 could not only act as a highly active Lewis acid catalyst for promoting the two-dimensional ordered polymerization of DCP monomers, but also in situ coordinate with the tridentate chelators generated between pyridine and triazine groups to yield unique Fe-N3 single-atom active sites in Fe-CTF. Abundant few-layer crystalline nanosheets (Fe-CTF NSs) could be prepared through simple ball-milling exfoliation of the bulk layered Fe-CTF and exhibited remarkable electrocatalytic performance for oxygen reduction reaction (ORR) with a half-wave potential and onset potential up to 0.902 and 1.02â
V respectively, and extraordinary Zn-air battery performance with an ultrahigh specific capacity and power density of 811â
mAh g-1 and 230â
mW cm-2 respectively. By combining operando X-ray absorption spectroscopy with density functional theory calculations, we revealed a dynamic and reversible evolution of Fe-N3 to Fe-N2 during the electrocatalytic process, which could further accelerate the electrocatalytic reaction.
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01-internacional
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MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2024
Tipo de documento:
Article