Efficient Co-N-C electrocatalysts for oxygen reduction derived from deep eutectic solvents

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F22%3A10459076" target="_blank" >RIV/00216208:11320/22:10459076 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=kJCABmdtQ~" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=kJCABmdtQ~</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.electacta.2022.140132" target="_blank" >10.1016/j.electacta.2022.140132</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Efficient Co-N-C electrocatalysts for oxygen reduction derived from deep eutectic solvents

Popis výsledku v původním jazyce

Cobalt-nitrogen-carbon (Co-N-C) systems are promising Pt-free catalysts for oxygen reduction reaction (ORR). Among other, ionic liquids (ILs) are currently being actively used as a source of nitrogen and carbon for obtaining Co-N-C electrocatalysts via pyrolysis. At the same time, known ILs-derived Co-N-C catalysts are characterized by either not high enough ORR activity or methods of their production are complex and multi-stage. Here, for the first time the possibility of increasing the efficiency of Co-N-C ORR electrocatalysts due to the use in precursor composition of deep eutectic solvents (DES) based on 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) or tetrafluoroborate ([Bmim]BF4) and hydrated Co(NO3)(2) or CoCl2 instead of mixture of IL and salt of Co (II) was shown. The advantages of using DES as precursors are the high content of cobalt and nitrogen in them, as well as the ability to provide uniform distribution of Co and N atoms in the electrocatalyst given the structure of DES. It was found that DES nature afects composition catalysts and the type of domanant active sites, which leads to diferences in their catalytic performance towards ORR. It was shown, that obtained Co-N-C electrocatalysts in their ORR-activity in the alkaline electrolyte (onset potential of 0.96-0.99 V vs. RHE, half-wave potential of 0.85-0.89 V, and a Tafel slope of 37-50 mV/dec) are almost not inferior to Pt/C catalyst, and are also characterized by high long-term electrochemical stability. The reduction of oxygen on the DES-derived Co-N-C catalysts is mainly occurs under 4-electron mechanism.

Název v anglickém jazyce

Efficient Co-N-C electrocatalysts for oxygen reduction derived from deep eutectic solvents

Popis výsledku anglicky

Cobalt-nitrogen-carbon (Co-N-C) systems are promising Pt-free catalysts for oxygen reduction reaction (ORR). Among other, ionic liquids (ILs) are currently being actively used as a source of nitrogen and carbon for obtaining Co-N-C electrocatalysts via pyrolysis. At the same time, known ILs-derived Co-N-C catalysts are characterized by either not high enough ORR activity or methods of their production are complex and multi-stage. Here, for the first time the possibility of increasing the efficiency of Co-N-C ORR electrocatalysts due to the use in precursor composition of deep eutectic solvents (DES) based on 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) or tetrafluoroborate ([Bmim]BF4) and hydrated Co(NO3)(2) or CoCl2 instead of mixture of IL and salt of Co (II) was shown. The advantages of using DES as precursors are the high content of cobalt and nitrogen in them, as well as the ability to provide uniform distribution of Co and N atoms in the electrocatalyst given the structure of DES. It was found that DES nature afects composition catalysts and the type of domanant active sites, which leads to diferences in their catalytic performance towards ORR. It was shown, that obtained Co-N-C electrocatalysts in their ORR-activity in the alkaline electrolyte (onset potential of 0.96-0.99 V vs. RHE, half-wave potential of 0.85-0.89 V, and a Tafel slope of 37-50 mV/dec) are almost not inferior to Pt/C catalyst, and are also characterized by high long-term electrochemical stability. The reduction of oxygen on the DES-derived Co-N-C catalysts is mainly occurs under 4-electron mechanism.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

—

Návaznosti

—

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

Electrochimica Acta

ISSN

0013-4686

e-ISSN

1873-3859

Svazek periodika

413

Číslo periodika v rámci svazku

May

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

9

Strana od-do

140132

Kód UT WoS článku

000831566600004

EID výsledku v databázi Scopus

2-s2.0-85126321259