---
_id: '61982'
abstract:
- lang: eng
  text: Doped Co3O4 nanoparticles are investigated via spectro-electrochemistry in
    the (pre-) oxygen evolution reaction (OER) regime by tracing the absorption signal
    of the Co3+ d–d transition under applied bias for getting insight into the catalysts
    activation and the formation of catalytically active phases. In the low potential
    regime up to 1.37 VRHE, a rise in the optical absorption signal of the [Co3+]oct
    d–d transition is observed and attributed to a structural change from [Co2+]tet
    to [Co3+]oct due to an electrochemically induced surface restructuring with water.
    For applied potentials higher than 1.37 VRHE an overall offset of the absorption
    spectra in the UV–vis range, equivalent to a darkening of the materials is detected.
    This is attributed to the formation of a CoOx(OH)y skin layer as supported by
    high-energy X-ray diffraction (HE-XRD) measurements. We found that the kinetics
    of the Co3+ states are heavily influenced by the type of dopant with V-doped Co3O4
    exhibiting stable Co3+ states (>20 min) while the Mn-doped Co3O4 Co3+ states reduce
    within 36 s under reductive bias. We conclude that doping Co3O4 with transition
    metals affects the formation and potential-dependent thickness of the CoOx(OH)y
    skin layer as the catalytically active phase and the formation of long-time stable
    surface Co3+ states after activation in the first OER cycle.
article_type: original
author:
- first_name: L.
  full_name: Kampermann, L.
  last_name: Kampermann
- first_name: J.
  full_name: Klein, J.
  last_name: Klein
- first_name: T.
  full_name: Wagner, T.
  last_name: Wagner
- first_name: A.
  full_name: Kotova, A.
  last_name: Kotova
- first_name: C.
  full_name: Placke-Yan, C.
  last_name: Placke-Yan
- first_name: A.
  full_name: Yasar, A.
  last_name: Yasar
- first_name: L.
  full_name: Jacobse, L.
  last_name: Jacobse
- first_name: S.
  full_name: Lasagna, S.
  last_name: Lasagna
- first_name: Christian
  full_name: Leppin, Christian
  id: '117722'
  last_name: Leppin
- first_name: S.
  full_name: Schulz, S.
  last_name: Schulz
- first_name: Julia
  full_name: Linnemann, Julia
  id: '116779'
  last_name: Linnemann
  orcid: 0000-0001-6883-5424
- first_name: A.
  full_name: Bergmann, A.
  last_name: Bergmann
- first_name: B.
  full_name: Roldan Cuenya, B.
  last_name: Roldan Cuenya
- first_name: G.
  full_name: Bacher, G.
  last_name: Bacher
citation:
  ama: Kampermann L, Klein J, Wagner T, et al. Operando Analysis of the Pre-OER Activation
    of Metal-Doped Co<sub>3</sub>O<sub>4</sub> Nanoparticle Catalysts. <i>ACS Catalysis</i>.
    2025;15(21):18391-18403. doi:<a href="https://doi.org/10.1021/acscatal.5c03900">10.1021/acscatal.5c03900</a>
  apa: Kampermann, L., Klein, J., Wagner, T., Kotova, A., Placke-Yan, C., Yasar, A.,
    Jacobse, L., Lasagna, S., Leppin, C., Schulz, S., Linnemann, J., Bergmann, A.,
    Roldan Cuenya, B., &#38; Bacher, G. (2025). Operando Analysis of the Pre-OER Activation
    of Metal-Doped Co<sub>3</sub>O<sub>4</sub> Nanoparticle Catalysts. <i>ACS Catalysis</i>,
    <i>15</i>(21), 18391–18403. <a href="https://doi.org/10.1021/acscatal.5c03900">https://doi.org/10.1021/acscatal.5c03900</a>
  bibtex: '@article{Kampermann_Klein_Wagner_Kotova_Placke-Yan_Yasar_Jacobse_Lasagna_Leppin_Schulz_et
    al._2025, title={Operando Analysis of the Pre-OER Activation of Metal-Doped Co<sub>3</sub>O<sub>4</sub>
    Nanoparticle Catalysts}, volume={15}, DOI={<a href="https://doi.org/10.1021/acscatal.5c03900">10.1021/acscatal.5c03900</a>},
    number={21}, journal={ACS Catalysis}, publisher={American Chemical Society (ACS)},
    author={Kampermann, L. and Klein, J. and Wagner, T. and Kotova, A. and Placke-Yan,
    C. and Yasar, A. and Jacobse, L. and Lasagna, S. and Leppin, Christian and Schulz,
    S. and et al.}, year={2025}, pages={18391–18403} }'
  chicago: 'Kampermann, L., J. Klein, T. Wagner, A. Kotova, C. Placke-Yan, A. Yasar,
    L. Jacobse, et al. “Operando Analysis of the Pre-OER Activation of Metal-Doped
    Co<sub>3</sub>O<sub>4</sub> Nanoparticle Catalysts.” <i>ACS Catalysis</i> 15,
    no. 21 (2025): 18391–403. <a href="https://doi.org/10.1021/acscatal.5c03900">https://doi.org/10.1021/acscatal.5c03900</a>.'
  ieee: 'L. Kampermann <i>et al.</i>, “Operando Analysis of the Pre-OER Activation
    of Metal-Doped Co<sub>3</sub>O<sub>4</sub> Nanoparticle Catalysts,” <i>ACS Catalysis</i>,
    vol. 15, no. 21, pp. 18391–18403, 2025, doi: <a href="https://doi.org/10.1021/acscatal.5c03900">10.1021/acscatal.5c03900</a>.'
  mla: Kampermann, L., et al. “Operando Analysis of the Pre-OER Activation of Metal-Doped
    Co<sub>3</sub>O<sub>4</sub> Nanoparticle Catalysts.” <i>ACS Catalysis</i>, vol.
    15, no. 21, American Chemical Society (ACS), 2025, pp. 18391–403, doi:<a href="https://doi.org/10.1021/acscatal.5c03900">10.1021/acscatal.5c03900</a>.
  short: L. Kampermann, J. Klein, T. Wagner, A. Kotova, C. Placke-Yan, A. Yasar, L.
    Jacobse, S. Lasagna, C. Leppin, S. Schulz, J. Linnemann, A. Bergmann, B. Roldan
    Cuenya, G. Bacher, ACS Catalysis 15 (2025) 18391–18403.
date_created: 2025-10-24T07:49:21Z
date_updated: 2025-12-07T17:15:53Z
department:
- _id: '985'
doi: 10.1021/acscatal.5c03900
intvolume: '        15'
issue: '21'
keyword:
- electrocatalysis
- oxygen evolution reaction
- cobalt spinel
- operando characterization
- spectroelectrochemistry
language:
- iso: eng
page: 18391-18403
publication: ACS Catalysis
publication_identifier:
  issn:
  - 2155-5435
  - 2155-5435
publication_status: published
publisher: American Chemical Society (ACS)
quality_controlled: '1'
status: public
title: Operando Analysis of the Pre-OER Activation of Metal-Doped Co<sub>3</sub>O<sub>4</sub>
  Nanoparticle Catalysts
type: journal_article
user_id: '116779'
volume: 15
year: '2025'
...