Water-oxidation catalysis by manganese in a geochemical-like cycle

Rosalie K. Hocking, Robin Brimblecombe, Lan Yun Chang, Archana Singh, Mun Hon Cheah, Chris Glover, William H. Casey, Leone Spiccia

Research output: Contribution to journalArticle

388 Scopus citations

Abstract

Water oxidation in all oxygenic photosynthetic organisms is catalysed by the Mn4CaO4 cluster of Photosystem II. This cluster has inspired the development of synthetic manganese catalysts for solar energy production. A photoelectrochemical device, made by impregnating a synthetic tetranuclear-manganese cluster into a Nafion matrix, has been shown to achieve efficient water oxidation catalysis. We report here in situ X-ray absorption spectroscopy and transmission electron microscopy studies that demonstrate that this cluster dissociates into Mn(II) compounds in the Nafion, which are then reoxidized to form dispersed nanoparticles of a disordered Mn(III/IV)-oxide phase. Cycling between the photoreduced product and this mineral-like solid is responsible for the observed photochemical water-oxidation catalysis. The original manganese cluster serves only as a precursor to the catalytically active material. The behaviour of Mn in Nafion therefore parallels its broader biogeochemistry, which is also dominated by cycles of oxidation into solid Mn(III/IV) oxides followed by photoreduction to Mn2+.

Original languageEnglish (US)
Pages (from-to)461-466
Number of pages6
JournalNature Chemistry
Volume3
Issue number6
DOIs
StatePublished - Jun 1 2011
Externally publishedYes

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

Fingerprint Dive into the research topics of 'Water-oxidation catalysis by manganese in a geochemical-like cycle'. Together they form a unique fingerprint.

  • Cite this

    Hocking, R. K., Brimblecombe, R., Chang, L. Y., Singh, A., Cheah, M. H., Glover, C., Casey, W. H., & Spiccia, L. (2011). Water-oxidation catalysis by manganese in a geochemical-like cycle. Nature Chemistry, 3(6), 461-466. https://doi.org/10.1038/nchem.1049