Spectroscopic studies into the light-driven production of H2 from an analogue of the active site of [NiFe] hydrogenase

• Main Author: Summers, Peter Andrew
• Published: University of Nottingham 2013
• Subjects: 660.295
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602429

A brief introduction to artificial photosynthesis and hydrogenase enzymes is provided. The characterisation of reactive intermediates using time-resolved spectroscopy is also discussed in relation to studying photocatalytic water splitting. Chapter 2. [Re(CO)3Cl(bpy)] has been used as a photosensitiser to drive the energetically uphill reduction of a catalyst, [NiFe2], by an electron donor. The intermediates within this photochemical reduction and the subsequent H2 evolution were studied using time-resolved spectroscopic techniques. The chemistry of [NiFe2] and its reduced products have been investigated in CH3CN, DMF and CH2Cl2 solutions with the effect on photocatalysis dis·cussed. The artificial photosynthetic system incorporating [Re(CO)3Cl(bpy)] and [NiFe2] in CH3CN was shown to evolve H2 on photolysis. This represents the first example of photocatalytic H2 production incorporating an analogue of the active site of [NiFe] hydrogenase. Chapter 3. [Ru(bpyh][PF6h was investigated in place of [Re(CO)3Cl(bpy)] with comparISons made between the two photosensitisers in terms of electron transfer kinetics and their ability to sustain photocatalaytic activity from [NiFe2]. The compounds [Re(CO)3X(diimine)] (diimine = bpy, phen, dpq, dppz and dppz-Me2; X = cr or NCS-) were then tested as photosensitisers through the systematic variation of the diimine ligand and the axial ligand (X).