Fe Isolated Single Atoms on S, N Codoped Carbon by Copolymer Pyrolysis Strategy for Highly Efficient Oxygen Reduction Reaction.
Adv Mater
; 30(25): e1800588, 2018 Jun.
Article
in En
| MEDLINE
| ID: mdl-29726038
Heteroatom-doped Fe-NC catalyst has emerged as one of the most promising candidates to replace noble metal-based catalysts for highly efficient oxygen reduction reaction (ORR). However, delicate controls over their structure parameters to optimize the catalytic efficiency and molecular-level understandings of the catalytic mechanism are still challenging. Herein, a novel pyrrole-thiophene copolymer pyrolysis strategy to synthesize Fe-isolated single atoms on sulfur and nitrogen-codoped carbon (Fe-ISA/SNC) with controllable S, N doping is rationally designed. The catalytic efficiency of Fe-ISA/SNC shows a volcano-type curve with the increase of sulfur doping. The optimized Fe-ISA/SNC exhibits a half-wave potential of 0.896 V (vs reversible hydrogen electrode (RHE)), which is more positive than those of Fe-isolated single atoms on nitrogen codoped carbon (Fe-ISA/NC, 0.839 V), commercial Pt/C (0.841 V), and most reported nonprecious metal catalysts. Fe-ISA/SNC is methanol tolerable and shows negligible activity decay in alkaline condition during 15â000 voltage cycles. X-ray absorption fine structure analysis and density functional theory calculations reveal that the incorporated sulfur engineers the charges on N atoms surrounding the Fe reactive center. The enriched charge facilitates the rate-limiting reductive release of OH* and therefore improved the overall ORR efficiency.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Adv Mater
Journal subject:
BIOFISICA
/
QUIMICA
Year:
2018
Document type:
Article
Affiliation country:
China
Country of publication:
Germany