|
|||||
|
|
Linking Composition,Structure and Thickness of CoOOH layers to Oxygen Evolution Reaction Activity by Correlative Microscopy |
|
| Authors: | Chenglong Luan Johanna Angona Arjun Bala Krishnan Manuel Corva Pouya Hosseini Markus Heidelmann Ulrich Hagemann Emmanuel Batsa Tetteh Wolfgang Schuhmann Kristina Tschulik Tong Li |
| Affiliation: | 1. Institute for Materials, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany These authors contributed equally to this work.;2. Faculty of Chemistry and Biochemistry, Analytical Chemistry II, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany These authors contributed equally to this work.;3. Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Straße 1, 40237 Düsseldorf, Germany;4. Interdisciplinary Center for Analytics on the Nanoscale (ICAN) and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Carl-Benz-Straße 199, 47057 Duisburg, Germany;5. Faculty of Chemistry and Biochemistry, Analytical Chemistry, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany;6. Faculty of Chemistry and Biochemistry, Analytical Chemistry II, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany;7. Institute for Materials, Ruhr-Universität Bochum, Universitätsstraße 150, 44801 Bochum, Germany |
| Abstract: | The role of β-CoOOH crystallographic orientations in catalytic activity for the oxygen evolution reaction (OER) remains elusive. We combine correlative electron backscatter diffraction/scanning electrochemical cell microscopy with X-ray photoelectron spectroscopy, transmission electron microscopy, and atom probe tomography to establish the structure–activity relationships of various faceted β-CoOOH formed on a Co microelectrode under OER conditions. We reveal that ≈6 nm β-CoOOH(01 0), grown on [ 0]-oriented Co, exhibits higher OER activity than ≈3 nm β-CoOOH(10 3) or ≈6 nm β-CoOOH(0006) formed on [02 - and [0001]-oriented Co, respectively. This arises from higher amounts of incorporated hydroxyl ions and more easily reducible CoIII−O sites present in β-CoOOH(01 0) than those in the latter two oxyhydroxide facets. Our correlative multimodal approach shows great promise in linking local activity with atomic-scale details of structure, thickness and composition of active species, which opens opportunities to design pre-catalysts with preferred defects that promote the formation of the most active OER species. |
| Keywords: | Atom Probe Tomography Cobalt Oxyhydroxide Identical Location Microscopy Scanning Electrochemical Cell Microscopy Water Splitting |