Towards Artificial Photosynthesis: Molecular and Materials Design for Water Oxidation


Event details

Date 17.11.2016
Hour 16:0017:00
Speaker Prof. Greta Patzke
Department of Chemistry, Uni. Zurich, Switzerland
Category Conferences - Seminars
Artificial photosynthesis has been in the focus of worldwide clean energy research for decades, because it provides direct access to hydrogen through solar-light water splitting. However, the development of efficient water oxidation catalysts remains a major bottleneck to master this demanding half reaction of water splitting on the way to technological implementations [1].
The talk will start with a basic overview of the current challenges of water oxidation catalyst (WOC) design together with an introduction to the UZH Research Priority Program LightChEC (Light to Chemical Energy Conversion).
In the first part, our bio-inspired strategies to molecular WOCs along the lines of Nature's {CaMn4O2} oxygen evolving complex (OEC) will be presented. We aim to translate OEC features into efficient Co-based WOCs, which led to the development of the first cuboidal {Co(II)4O4} WOC with a flexible ligand environment.[2] The key functional elements of this Co-cubane WOC will be compared to the first series of highly sought-after active cubane WOCs combining mobile ligands with a bio-mimetic redox-inert center, namely the [Coll3Ln(hmp)4(OAc)5H2O] (Ln = Ho - Yb, hmp = 2-(hydroxymethyl)pyridine) cubanes.[3] Crucial issues in molecular catalyst construction will be discussed, including core nuclearity, ligand architecture/exchange and the role of Ln3 cations as Ca2+ mimics.
The second part of the talk will complement molecular catalysis with our recent strategies towards heterogeneous Co-containing WOCs, such as robust spinel- and perovskite-based systems. Special emphasis will be placed on La1-xSrxBO3 perovskites (B = Fe, Co, Ni or Mn) as model systems for electronic structure tuning as a straightforward strategy toward solid WOC optimization.[4] An outlook on unified WOC design approaches will be round off the talk.
[1] M. D. Karkas, O. Verho, E. V. Johnston, B. Akermark, Chem. Rev. 2014, 114, 11863.
[2] F. Evangelisti, R. Güttinger, R. Moré, S. Luber, G. R. Patzke*, J. Am. Chem. Soc. 2013, 135, 18734. 
[3] F. Evangelisti, R. Moré, F. Hodel, S. Luber*, G. R. Patzke*, J. Am. Chem. Soc. 2015, 137, 11076.
[4] H. Liu, R. Moré, H. Grundmann, C. Cui, R. Erni, G. R. Patzke, J. Am. Chem. Soc. 2016, 138, 1527.

Practical information

  • General public
  • Free


  • Prof. Hubert Girault


  • Evelyn Ludi