3D atomic-scale imaging of mixed Co-Fe spinel oxide nanoparticles during oxygen evolution reaction

DOI: 10.1038/s41467-021-27788-2

Authors: Weikai Xiang (Ruhr-Universität Bochum) , Nating Yang (Shanghai Advanced Research Institute (SARI), Chinese Academy of Sciences (CAS)) , Xiaopeng Li (Donghua University) , Julia Linnemann (Ruhr-Universität Bochum) , Ulrich Hagemann (University of Duisburg-Essen) , Olaf Ruediger (Max Planck Institute for Chemical Energy Conversion) , Markus Heidelmann (University of Duisburg-Essen) , Tobias Falk (Ruhr-Universität Bochum) , Matteo Aramini (Diamond Light Source) , Serena Debeer (Max Planck Institute for Chemical Energy Conversion) , Martin Muhler (Ruhr-Universität Bochum) , Kristina Tschulik (Ruhr-Universität Bochum) , Tong Li (Ruhr-Universität Bochum)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 13

State: Published (Approved)
Published: January 2022
Diamond Proposal Number(s): 25636

Abstract: The three-dimensional (3D) distribution of individual atoms on the surface of catalyst nanoparticles plays a vital role in their activity and stability. Optimising the performance of electrocatalysts requires atomic-scale information, but it is difficult to obtain. Here, we use atom probe tomography to elucidate the 3D structure of 10 nm sized Co2FeO4 and CoFe2O4 nanoparticles during oxygen evolution reaction (OER). We reveal nanoscale spinodal decomposition in pristine Co2FeO4. The interfaces of Co-rich and Fe-rich nanodomains of Co2FeO4 become trapping sites for hydroxyl groups, contributing to a higher OER activity compared to that of CoFe2O4. However, the activity of Co2FeO4 drops considerably due to concurrent irreversible transformation towards CoIVO2 and pronounced Fe dissolution. In contrast, there is negligible elemental redistribution for CoFe2O4 after OER, except for surface structural transformation towards (FeIII, CoIII)2O3. Overall, our study provides a unique 3D compositional distribution of mixed Co-Fe spinel oxides, which gives atomic-scale insights into active sites and the deactivation of electrocatalysts during OER.

Journal Keywords: Electrocatalysis; Imaging techniques; Nanoparticles

Subject Areas: Materials, Chemistry, Environment


Instruments: I20-Scanning-X-ray spectroscopy (XAS/XES)

Added On: 17/01/2022 11:45

Documents:
s41467-021-27788-2.pdf

Discipline Tags:

Surfaces Earth Sciences & Environment Physics Climate Change Physical Chemistry Catalysis Chemistry Materials Science Nanoscience/Nanotechnology

Technical Tags:

Spectroscopy X-ray Absorption Spectroscopy (XAS) High Energy Resolution Fluorescence Detected XAS (HERFD-XAS)