Diameter-dependent single- and double-file stacking of squaraine dye molecules inside chirality-sorted single-wall carbon nanotubes

Abstract

The filling of single-wall carbon nanotubes (SWCNTs) with dye molecules has become a novel path to add new functionalities through the mutual interaction of confined dyes and host SWCNTs. In...

Efficient Inner-to-Outer Wall Energy Transfer in Highly Pure Double-Wall Carbon Nanotubes Revealed by Detailed Spectroscopy

“…A possible explanation for this drastically quenched fluorescence of the inner DWCNT walls is the earlier postulated ET from the inner to the outer wall of the DWCNTs. , This transfer occurs because the larger outer walls naturally have a smaller band gap compared to those of the inner walls. In 2D PLE, such an ET would express itself as an additional peak at the crossing point of the excitation wavelength of the inner DWCNT wall and the emission wavelength of the corresponding outer DWCNT wall, similarly to the observed ET from encapsulated dye molecules to surrounding SWCNTs. , Also in SWCNT bundles, efficient and ultrafast energy transfer to the smallest band gaps has been observed previously. , In our samples, where extensive DGU sorting was applied, the presence of such bundles can be neglected. In Figure , we therefore present the 2D PLE maps of the P-S@S-DWCNT-1 and P-S@S-DWCNT-2 samples, with a zoomed-in intensity color scale as compared to Figure , to search for such cross peaks.…”

“…In 2D PLE, such an ET would express itself as an additional peak at the crossing point of the excitation wavelength of the inner DWCNT wall and the emission wavelength of the corresponding outer DWCNT wall, similarly to the observed ET from encapsulated dye molecules to surrounding SWCNTs. 50,51 Also in SWCNT bundles, efficient and ultrafast energy transfer to the smallest band gaps has been observed previously. 52,53 In our samples, where extensive DGU sorting was applied, the presence of such bundles can be neglected.…”

“…In this respect, for each inner DWCNT chirality that shows a well-resolved ET peak within the measured excitation range, we added a Voigt line shape in the excitation profile of the outer DWCNT wall, corresponding to the excitation of the inner DWCNT chirality (see Supporting Information section S3 for more details). This adaptation of the model is quite similar to what was employed in refs and for the fitting of the ET of encapsulated dyes inside SWCNTs but different in the sense that now, for each outer DWCNT chirality, multiple inner DWCNT chiralities could show an ET peak (because of the different inner@outer wall combinations). To accurately fit these ET peaks, the PLE maps of the DWCNT samples were fitted simultaneously, with shared peak positions and line widths for the outer wall emission peaks.…”

“…To assess these ET peaks in more detail, we fitted all the PLE maps using our previously developed 2D fit model for SWCNT PLE maps. 40 , 41 , 50 , 51 , 54 , 55 While for the SWCNT PLE maps (see results in Figures S17 & S18 ) the previous model could be directly employed, we adapt the model to also fit the ET peaks of particular inner@outer wall combinations in the PLE map. In this respect, for each inner DWCNT chirality that shows a well-resolved ET peak within the measured excitation range, we added a Voigt line shape in the excitation profile of the outer DWCNT wall, corresponding to the excitation of the inner DWCNT chirality (see Supporting Information section S3 for more details).…”

Simultane Funktionalisierung von Einwandigen Kohlenstoff‐Nanoröhren von Innen und Außen

“…Die bekanntesten Beispiele sind die so genannten "Fulleren-Peapods", [32,33] die aus CNTs mit relativ großem Durchmesser bestehen, die mit Fullerenen gefüllt sind. Die Verkapselung von Farbstoffen [34] und kleineren atomaren Gästen wurde ebenfalls nachgewiesen, z. B. für Schwefel, [35] Iod, [36][37][38] Alkalimetalle [39] und sogar Krypton.…”