Self-Assembled Copper Nanoclusters for Electrocatalytic Glucose Oxidation

Metal nanoclusters (NCs) protected by a thiolate ligand are fascinating for their unique geometrical structures and physicochemical properties. Herein, a ligand-based strategy to tailor the structures and electrocatalytic properties of self-assembled Cu NCs was proposed. By adjusting the molar ratio of two protected ligands (2,3,5,6-tetrafluorothiophenol and 2,3,4,5,6-pentafluorothiophenol), the morphology of assembled Cu NCs was changed from nanoribbons to ultrathin nanowires, nanonetworks, and then to nanosheets, which was similar to the weaving process of silk. When the fluorine substitution of thiophenol ligands increased from tetrasubstitution to pentasubstitution, the composition, geometrical structure, optical absorption spectrum, charge distribution, and electrostatic potential of Cu NCs changed and then affected the assembled architectures and the electrocatalytic activity of Cu NCs for glucose oxidation. On the basis of the excellent electrocatalytic performance of assembled Cu NCs, the as-prepared nanoribbons were successfully used for nonenzymatic electrochemical detection of glucose with a wider linear range located between 5 μM and 26 mM.