Electronic Reduction of CO2 by Bipyrimidine-Bridged Trimetallic Complexes {[(bpy)2Ru(bpm)]2MCl2}5+ Where M=IrIII or RhIII
The electrocatalytic activity of the bipyrimidine-bridged trimetallic complexes of the form, {[(bpy)2Ru(bpm)]2MCl2}5+ where bpy = 2,2’-bipyridine, bpm = 2,2’-bipyrimidine and M = RhIII or IrIII in the reduction of carbon dioxide was investigated. The electrochemistry of these complexes differ upon variation of the central metal from iridium to rhodium. In effect, this resulted in a significant shift of the reduction potential for the electrochemical conversion of CO2 into products. Electrocatalytic studies using these bpm systems showed a shift in the CO2 reduction potential from -1.80 V to -1.00 V vs. Ag/AgCl for iridium(III) and rhodium(III) as catalytic centers, respectively. CO and HCOOH were the detectable CO2 reduction products using both trimetallic complexes as electrocatalysts. Details of the catalytic investigations were described herein.
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