title: Single-wall carbon nanotubes bearing covalently linked phthalocyanines--photoinduced electron transfer.
abstract: HiPco single-walled carbon nanotubes (SWNTs) have been sidewall-functionalized with phthalocyanine addends following two different approaches: a straightforward Prato reaction with N-octylglycine and a formyl-containing phthalocyanine, and a stepwise approach that involves a former Prato cycloaddition to the double bonds of SWNTs using p-formyl benzoic acid followed by esterification of the derivatized nanotubes with an appropriate phthalocyanine molecule. The two materials obtained by these routes comprise different carbon/Pc-addenda ratios, as evidenced by Raman, TGA, and photophysical studies. The occurrence of electron transfer from photoexcited phthalocyanines to the nanotube framework in these ZnPc-SWNT ensembles is observed in transient absorption experiments, which confirm the absorption of the one-electron oxidized ZnPc cation and the concomitant bleaching of the van Hove singularities typical from SWNTs. Charge-separation (i.e., 2.0 x 1010 s(-1)) and charge-recombination (i.e., 1.5 x 106 s(-1)) dynamics reveal a notable stabilization of the radical ion pair product in dimethylformamide.
authors.affiliation: Departamento de Química OrgAnica, Universidad Autónoma de Madrid, Cantoblanco 28049-Madrid, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Ballesteros
authors.forename: Gema de la
authors.initials: Gde L
authors.lastname: Torre
authors.forename: Christian
authors.initials: C
authors.lastname: Ehli
authors.forename: G M Aminur
authors.initials: GM
authors.lastname: Rahman
authors.forename: F
authors.initials: F
authors.lastname: Agulló-Rueda
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Guldi
authors.forename: Tomas
authors.initials: T
authors.lastname: Torres