Electrochemical reduction of Cu2+ without surface trapping on synthetic conductive diamond electrodes

The electrochemical reduction of metal ions is commonly referred to as `electrodepositionʹ because the reduced metal is trapped on the surface, and a new solid phase is formed. We present evidence for a clear deviation from this general concept on the conductive boron-doped CVD diamond electrode, where the electrochemical reduction of copper proceeds with negligible deposition of the metal on the electrode and the product is a colloid composed of the metal clusters.