Résumé
A multiwalled carbon nanotube (MWCNT) scaffold was covalently functionalized with a second-generation polyamidoamine (PAMAM) dendron, presenting four terminal amino groups per grafted aryl moiety. These reactive functions were alkylated to obtain a positively charged polycationic dendron/carbon nanotube system (d-MWCNTs·Cl), which eventually underwent anion exchange reaction with a negatively charged and highly luminescent Eu complex ([EuL ]·NEt , in which L=(2-naphtoyltrifluoroacetonate)). This process afforded the target material d-MWCNTs·[EuL ], in which MWCNTs are combined with red-emitting Eu centers through electrostatic interactions with the dendronic branches. Characterization of the novel MWCNT materials was accomplished by means of TGA and TEM, whereas d-MWCNTs·Cl and d-MWCNTs· [EuL ] further underwent XPS, SEM and Raman analyses. These studies demonstrate the integrity of the luminescent [EuL ] center in the luminescent hybrid, the massive load of the cationic binding sites, and the virtually complete anion-exchange into the final hybrid material. The occurrence of the ion-pairing interaction with MWCNTs was unambiguously demonstrated through DOSY NMR diffusion studies. Photophysical investigations show that MWCNTs·[EuL ] is a highly soluble and brightly luminescent red hybrid material in which MWCNTs act as photochemically inert scaffolds with negligible UV/Vis absorption, compared with the grafted Eu complex, and with no quenching activity. The high dispersibility of MWCNTs·[EuL ] in a polymer matrix makes it a promising luminophore for applications in material science.
langue originale | Anglais |
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Pages (de - à) | 5889-5897 |
Nombre de pages | 9 |
journal | Chemistry: A European Journal |
Volume | 18 |
Numéro de publication | 19 |
Les DOIs | |
Etat de la publication | Publié - 7 mai 2012 |