Deutsch
 
Hilfe Datenschutzhinweis Impressum
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT

Freigegeben

Zeitschriftenartikel

Key role of chemistry versus bias in electrocatalytic oxygen evolution

MPG-Autoren
/persons/resource/persons206719

Falling,  Lorenz
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons214068

Bergmann,  Arno
Interface Science, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons206875

Mom,  Rik
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons227619

Timoshenko,  Janis
Interface Science, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons21743

Knop-Gericke,  Axel
Department of Heterogeneous Reactions, Max-Planck-Institute for Chemical Energy Conversion;
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons22020

Roldan Cuenya,  Beatriz
Interface Science, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons22071

Schlögl,  Robert
Department of Heterogeneous Reactions, Max-Planck-Institute for Chemical Energy Conversion;
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons22163

Teschner,  Detre
Department of Heterogeneous Reactions, Max-Planck-Institute for Chemical Energy Conversion;
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons135780

Jones,  Travis
Inorganic Chemistry, Fritz Haber Institute, Max Planck Society;

Externe Ressourcen
Es sind keine externen Ressourcen hinterlegt
Volltexte (beschränkter Zugriff)
Für Ihren IP-Bereich sind aktuell keine Volltexte freigegeben.
Volltexte (frei zugänglich)

3265127.pdf
(beliebiger Volltext), 204KB

Ergänzendes Material (frei zugänglich)
Es sind keine frei zugänglichen Ergänzenden Materialien verfügbar
Zitation

Nong, H. N., Falling, L., Bergmann, A., Klingenhof, M., Tran, H. P., Spöri, C., et al. (2020). Key role of chemistry versus bias in electrocatalytic oxygen evolution. Nature, 587, 408-413. doi:10.1038/s41586-020-2908-2.


Zitierlink: https://hdl.handle.net/21.11116/0000-0007-7532-D
Zusammenfassung
The oxygen evolution reaction has an important role in many alternative-energy schemes because it supplies the protons and electrons required for converting renewable electricity into chemical fuels. Electrocatalysts accelerate the reaction by facilitating the required electron transfer, as well as the formation and rupture of chemical bonds5. This involvement in fundamentally different processes results in complex electrochemical kinetics that can be challenging to understand and control, and that typically depends exponentially on overpotential. Such behaviour emerges when the applied bias drives the reaction in line with the phenomenological Butler–Volmer theory, which focuses on electron transfer, enabling the use of Tafel analysis to gain mechanistic insight under quasi-equilibrium or steady-state assumptions. However, the charging of catalyst surfaces under bias also affects bond formation and rupture, the effect of which on the electrocatalytic rate is not accounted for by the phenomenological Tafel analysis8 and is often unknown. Here we report pulse voltammetry and operando X-ray absorption spectroscopy measurements on iridium oxide to show that the applied bias does not act directly on the reaction coordinate, but affects the electrocatalytically generated current through charge accumulation in the catalyst. We find that the activation free energy decreases linearly with the amount of oxidative charge stored, and show that this relationship underlies electrocatalytic performance and can be evaluated using measurement and computation. We anticipate that these findings and our methodology will help to better understand other electrocatalytic materials and design systems with improved performance.