2017年10月
Identification of catalytic sites in cobalt-nitrogen-carbon materials for the oxygen reduction reaction
NATURE COMMUNICATIONS
- 巻
- 8
- 号
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1038/s41467-017-01100-7
- 出版者・発行元
- NATURE PUBLISHING GROUP
Single-atom catalysts with full utilization of metal centers can bridge the gap between molecular and solid-state catalysis. Metal-nitrogen-carbon materials prepared via pyrolysis are promising single-atom catalysts but often also comprise metallic particles. Here, we pyrolytically synthesize a Co-N-C material only comprising atomically dispersed cobalt ions and identify with X-ray absorption spectroscopy, magnetic susceptibility measurements and density functional theory the structure and electronic state of three porphyrinic moieties, CoN4C12, CoN3C10,(porp) and CoN2C5. The O-2 electro-reduction and operando X-ray absorption response are measured in acidic medium on Co-N-C and compared to those of a Fe-N-C catalyst prepared similarly. We show that cobalt moieties are unmodified from 0.0 to 1.0 V versus a reversible hydrogen electrode, while Fe-based moieties experience structural and electronic-state changes. On the basis of density functional theory analysis and established relationships between redox potential and O-2-adsorption strength, we conclude that cobaltbased moieties bind O-2 too weakly for efficient O-2 reduction.
- リンク情報
- ID情報
-
- DOI : 10.1038/s41467-017-01100-7
- ISSN : 2041-1723
- Web of Science ID : WOS:000412999700025