A Robust Molecular Catalyst Generated In Situ for Photo- and Electrochemical Water Oxidation

Hussein A. Younus, Nazir Ahmad, Adeel H. Chughtai, Matthias Vandichel, Michael Busch, Kristof Van Hecke, Mekhman Yusubov, Shaoxian Song, Francis Verpoort

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Water splitting is the key step towards artificial photosystems for solar energy conversion and storage in the form of chemical bonding. The oxidation of water is the bottle-neck of this process that hampers its practical utility; hence, efficient, robust, and easy to make catalytic systems based on cheap and earth-abundant materials are of exceptional importance. Herein, an in situ generated cobalt catalyst, [CoII(TCA)2(H2O)2] (TCA=1-mesityl-1,2,3-1H-triazole-4-carboxylate), that efficiently conducts photochemical water oxidation under near-neutral conditions is presented. The catalyst showed high stability under photolytic conditions for more than 3 h of photoirradiation. During electrochemical water oxidation, the catalytic system assembled a catalyst film, which proved not to be cobalt oxide/hydroxide as normally expected, but instead, and for the first time, generated a molecular cobalt complex that incorporated the organic ligand bound to cobalt ions. The catalyst film exhibited a low overpotential for electrocatalytic water oxidation (360 mV) and high oxygen evolution peak current densities of 9 and 2.7 mA cm−2 on glassy carbon and indium-doped tin oxide electrodes, respectively, at only 1.49 and 1.39 V (versus a normal hydrogen electrode), respectively, under neutral conditions. This finding, exemplified on the in situ generated cobalt complex, might be applicable to other molecular systems and suggests that the formation of a catalytic film in electrochemical water oxidation experiments is not always an indication of catalyst decomposition and the formation of nanoparticles.

Original languageEnglish
Pages (from-to)862-875
Number of pages14
JournalChemSusChem
Volume10
Issue number5
DOIs
Publication statusPublished - 9 Mar 2017

Fingerprint

cobalt
catalyst
Cobalt
oxidation
Oxidation
Catalysts
Water
water
electrode
oxide
chemical bonding
indium
Electrodes
Indium
Triazoles
Glassy carbon
Bottles
Tin oxides
density current
tin

Keywords

  • cobalt
  • electrochemistry
  • oxidation
  • photochemistry
  • water splitting

ASJC Scopus subject areas

  • Environmental Chemistry
  • Chemical Engineering(all)
  • Materials Science(all)
  • Energy(all)

Cite this

Younus, H. A., Ahmad, N., Chughtai, A. H., Vandichel, M., Busch, M., Van Hecke, K., ... Verpoort, F. (2017). A Robust Molecular Catalyst Generated In Situ for Photo- and Electrochemical Water Oxidation. ChemSusChem, 10(5), 862-875. https://doi.org/10.1002/cssc.201601477

A Robust Molecular Catalyst Generated In Situ for Photo- and Electrochemical Water Oxidation. / Younus, Hussein A.; Ahmad, Nazir; Chughtai, Adeel H.; Vandichel, Matthias; Busch, Michael; Van Hecke, Kristof; Yusubov, Mekhman; Song, Shaoxian; Verpoort, Francis.

In: ChemSusChem, Vol. 10, No. 5, 09.03.2017, p. 862-875.

Research output: Contribution to journalArticle

Younus, HA, Ahmad, N, Chughtai, AH, Vandichel, M, Busch, M, Van Hecke, K, Yusubov, M, Song, S & Verpoort, F 2017, 'A Robust Molecular Catalyst Generated In Situ for Photo- and Electrochemical Water Oxidation', ChemSusChem, vol. 10, no. 5, pp. 862-875. https://doi.org/10.1002/cssc.201601477
Younus HA, Ahmad N, Chughtai AH, Vandichel M, Busch M, Van Hecke K et al. A Robust Molecular Catalyst Generated In Situ for Photo- and Electrochemical Water Oxidation. ChemSusChem. 2017 Mar 9;10(5):862-875. https://doi.org/10.1002/cssc.201601477
Younus, Hussein A. ; Ahmad, Nazir ; Chughtai, Adeel H. ; Vandichel, Matthias ; Busch, Michael ; Van Hecke, Kristof ; Yusubov, Mekhman ; Song, Shaoxian ; Verpoort, Francis. / A Robust Molecular Catalyst Generated In Situ for Photo- and Electrochemical Water Oxidation. In: ChemSusChem. 2017 ; Vol. 10, No. 5. pp. 862-875.
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