The preparation of aligned and/or micropatterned carbon nanotubes is important to applications ranging from nanocomposites to field-emitting displays. By pyrolysis of iron (II) phthalocyanine under Ar/H2 at 800−1100 °C, we have synthesized large arrays of vertically aligned carbon nanotubes on various substrates, including quartz glass plates, from which substrate-free films were obtained simply by immersing the nanotube-deposited quartz plates into an aqueous hydrofluoric acid solution. Micropatterns of the aligned nanotubes suitable for device fabrication were generated either by patterned growth of the nanotubes on a partially masked/prepatterned surface or through a contact printing process involving region-specific transfer of the substrate-free nanotube films to other substrates (e.g., polymer films), which otherwise may not be suitable for nanotube growth at high temperatures.

A novel approach for chemical modification of carbon nanotubes was developed, which involved radio frequency glow-discharge plasma activation, followed by chemical reactions characteristic of the plasmagenerated functional groups. For instance, amino-dextran chains have been immobilized onto acetaldehydeplasma-treated aligned carbon nanotubes through the formation of Schiff-base linkages, which were further stabilized by reduction with sodium cyanoborohydride. Using the same reaction, we have also chemically grafted periodate-oxidized dextran chains pre-labeled with fluorescein onto ethylenediamine-plasma-treated carbon nanotubes. The fluorescein labeling allows the surface immobilization reaction to be followed simply by photoluminescence measurements. The resulting polysaccharide-grafted carbon nanotubes are very hydrophilic, as demonstrated by X-ray photoelectron spectroscopic and air/water contact angle measurements.

The photophysical properties of a series of ruthenium trisbipyridine complexes covalently linked to aromatic chromophores of the type [Ru(bpy)2(4-methyl-4‘-(2-arylethyl)-2,2‘-bipyridine)]2+(ClO4)2, where aryl = 2-naphthyl ([Ru]-naphthalene), 1-pyrenyl ([Ru]-pyrene), and 9-anthryl ([Ru]-anthracene) have been investigated at room temperature and at 77 K. The photophysical properties of these bichromophores are determined by intramolecular energy-transfer processes that are governed by the relative positions of the various singlet and triplet energy levels. As a result, fluorescence from each of the pendant aromatic chromophores is completely quenched following their photoexcitation. For [Ru]-naphthalene the initial excitation energy is localized on the [Ru]-centered 3MLCT state, whereas for [Ru]-anthracene the energy is localized on the anthracene triplet state. Since the [Ru]-centered 3MLCT state and the lowest energy pyrene triplet state are isoenergetic, an equilibrium is established resulting in a long-lived room-temperature 3MLCT emission from [Ru]-pyrene (τ = 5.23 μs). At 77 K dual emission is observed from this bichromophore comprising pyrene phosphorescence and 3MLCT emission, the relative proportions of which vary with time after the laser pulse.

Composites of C60 fullerene and carbon nanotubes with polymers are attractive for a wide range of applications. The combination of the unique physicochemical and optoelectronic properties of the carbon structures with the characteristics of some well‐known polymers has proven to yield some interesting effects. Various synthetic approaches to making these advanced polymeric composites have been suggested along with novel methods for microstructuring the materials into aligned or patterned forms.

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