Identification of catalytic sites in cobalt-nitrogen-carbon materials for the oxygen reduction reaction

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F17%3A00481079" target="_blank" >RIV/61388955:_____/17:00481079 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1038/s41467-017-01100-7" target="_blank" >http://dx.doi.org/10.1038/s41467-017-01100-7</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1038/s41467-017-01100-7" target="_blank" >10.1038/s41467-017-01100-7</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Identification of catalytic sites in cobalt-nitrogen-carbon materials for the oxygen reduction reaction

Popis výsledku v původním jazyce

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.

Název v anglickém jazyce

Identification of catalytic sites in cobalt-nitrogen-carbon materials for the oxygen reduction reaction

Popis výsledku anglicky

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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Nature Communications

ISSN

2041-1723

e-ISSN

—

Svazek periodika

8

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

11

Strana od-do

—

Kód UT WoS článku

000412999700025

EID výsledku v databázi Scopus

2-s2.0-85031813002