| Abstract
| - New metallo-nanostructured materials of carbon nanohorns (CNHs), within the family of elongatedcarbon nanotubes, have been prepared by the coordination of copper(II)−2,2‘:6‘,2‘ ‘-terpyridine (CuIItpy)with oxidized carbon nanohorns (CNHs-COOH). The resulted CNHs-COO−CuIItpy metallo-nanocomplexeshave been characterized by diverse analytical spectroscopic tools and cyclic and differential pulsevoltammetry. Scanning transmission electron microscopy (STEM), dynamic light scattering (DLS), and energydispersive X-ray spectroscopy (EDX) measurements have been employed to probe the morphologicalcharacteristics and particle-size distribution of CNHs-COO−CuIItpy as well as to investigate the elementalcomposition of the metallo-nanocomplex. Steady-state and time-resolved fluorescence emission studieshave shown efficient fluorescence quenching, suggesting that electron transfer occurs from the singletexcited state of CuIItpy to CNHs. Photoexcitation of CuIItpy resulted in the one-electron reduction ofnanohorns with a simultaneous one-electron oxidation of the CuIItpy unit (CNHs•--COO−(CuIItpy)•+) asrevealed by transient absorption measurements. The charge-separated state of CNHs•--COO−(CuIItpy)•+has been confirmed with the aid of an electron mediator, such as hexyl-viologen dication (HV2+) and anelectron−hole shifter in polar solvents.
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