title: Ruthenium porphyrin functionalized single-walled carbon nanotube arrays--a step toward light harvesting antenna and multibit information storage.
abstract: Ruthenium porphyrin functionalized single-walled carbon nanotube arrays have been prepared using coordination of the axial position of the metal ion onto 4-aminopyridine preassembled single-walled carbon nanotubes directly anchored to a silicon(100) surface (SWCNTs-Si). The formation of these ruthenium porphyrin functionalized single-walled carbon nanotube array electrodes (RuTPP-SWCNTs-Si) has been monitored using infrared spectroscopy (IR), differential pulse voltammetry (DPV), atomic force microscopy (AFM), laser desorption time-of-flight mass spectroscopy (LDI-TOF-MS), UV-vis spectroscopy, fluorescence spectroscopy, and cyclic voltammetry. Electrochemical results show two successive one-electron reversible redox waves. The surface concentration of the ruthenium porphyrin molecules is 3.44 x 10 (-8) mol cm (-2). Optical results indicate that the immobilization of ruthenium porphyrin enhances the light absorption of SWCNTs-Si surfaces in the visible light region. Moreover mixed assembly of ferrocene/porphyrin onto carbon nanotube arrays has been achieved by altering the ratio of two redox-active species in the deposition solution. These results suggest the ruthenium porphyrin modified electrodes are excellent candidates for molecular memory devices and light harvesting antennae.
authors.affiliation: School of Chemistry, Physics and Earth Sciences, Flinders University, Bedford Park, SA 5042, Australia.
authors.forename: Jingxian
authors.initials: J
authors.lastname: Yu
authors.forename: Simon
authors.initials: S
authors.lastname: Mathew
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Flavel
authors.forename: Martin R
authors.initials: MR
authors.lastname: Johnston
authors.forename: Joe G
authors.initials: JG
authors.lastname: Shapter