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The clean production of hydrogen from renewable sources utilising earth-abundant
catalysts is a major societal challenge. In this talk we will use nature as an inspiration.
Hydrogenases, [FeFe]ases, are ancient enzymes capable of catalysing the reversible
formation of hydrogen from protons and electrons. The active site of [FeFe]ases contains six
iron atoms, a well-known ferredoxin sub-unit being linked to an unusual diiron carbonylcyanide
stabilised centre via a cysteine group. In our work we have been concerned with
both gaining a better understanding of how these enzymes work, while having the major
goal of preparing cheap and robust iron complexes that can act as functional mimics, thus
allowing the industrial scale production of hydrogen from renewable sources (wind, wave,
solar etc.) and protons. In this talk we will consider four aspects of this work, (i)
differentiating between the catalytic activity of isomeric diiron complexes, (ii) the
interaction between the catalytically active diiron centre and an attached redox-active
ligand, (iii) the potential use of triiron complexes s catalysts containing a proton-shuttle and
(iv) an enzyme mimic that can both catalyse the production and oxidation (essential to a fuel
cell) of hydrogen.
Models of the iron-only hydrogenase: A comparison of chelate and bridge isomers of Fe2(CO)4{Ph2PN(R)PPh2}( -
pdt) as proton reduction catalysts, S. Ghosh, G. Hogarth, N. Hollingsworth, K. B. Holt, I. Richards, B. E. Sanchez
and D. Unwin, Dalton Transactions, 2013, 42, 6775-6792.
Hydrogenase biomimetics: Fe2(CO)4(-dppf)(-pdt) (dppf = 1,1’-bis(diphenylphosphino)ferrocene)) both a protonreduction
and hydrogen oxidation catalyst, S. Ghosh, G. Hogarth, N. Hollingsworth, K.B. Holt, S.E. Kabir and B.E.
Sanchez, Chemical Communications, 2014, 50, 945-947.
Electrocatalytic proton reduction catalysed by the low-valent tetrairon-oxo cluster [Fe4(CO)10(κ2
-dppn)(μ4-O)]2-
[dppn = 1,1′-bis(diphenylphosphino) naphthalene], S. Ghosh, K.B. Holt, S.E. Kabir, M.G. Richmond and G.
Hogarth, Dalton Trans., 2015, 44, 5160-5169.
Graeme Hogarth joined King’s College London as Director for
Teaching and Learning in early 2014 after spending the
previous 25 years across London at University College London.
His research interests cover a wide range of applications of
transition metal chemistry current themes being the synthesis
of bio-inspired base metal catalysts for the clean formation of
hydrogen and applications of functionalised dithiocarbamate
complexes in chemistry, materials science, anti-cancer drugs
and radiopharmaceuticals. Outside of chemistry he can often
be found on a squash court, where he coaches and competes,
or watching his sons play ice hockey. |