Copper(ii) defect-cubane water oxidation electrocatalysts: from molecular tetramers to oxidic nanostructures

We report on the synthesis and spectroscopic evidence for a sequence of structural transformations of a new defect-cubane type copper complex, [Cu-4(pyalk)(4)(OAc)(4)](ClO4)(HNEt3), which acts as a pre-catalyst for water oxidation. In situ and post-catalytic studies showed that the tetrameric complex undergoes a structural transformation into dimeric and monomeric species, induced by water molecules and carbonate anions, respectively. Further, the observed electrocatalytic water oxidation activity has been confirmed to arise from in situ-generated Cu(ii) oxidic nanostructures at the electrode interface.

Automated summary

This report presents the synthesis and spectroscopic evidence of a new defect-cubane type copper complex that acts as a pre-catalyst for water oxidation. In situ and post-catalytic studies reveal that the tetrameric complex undergoes structural transformations into dimeric and monomeric species induced by water molecules and carbonate anions, respectively. Moreover, the observed electrocatalytic water oxidation activity is confirmed to arise from in situ-generated Cu(ii) oxidic nanostructures at the electrode interface.