U-shaped bisporphyrin molecules are clipped around SWCNTs using ring-closing metathesis yielding rotaxane-type derivatives, in which porphyrins and SWCNTs are connected through mechanical links.

A series of molecular precursors, containing one (1 and 3) or three (2 and 4) pyrene anchors, covalently linked to porphyrins (free base or Zn), were prepared and characterized. All of them enable their π−π stacking onto low-dimensional nanocarbons including single-walled carbon nanotubes (SWCNTs) and nanographene (NG), their individualization, and their characterization. Microscopic (TEM, AFM) and spectroscopic (steady-state UV−vis and fluorescence, spectroelectrochemistry, and transient absorption measurements) techniques were at the forefront of the characterizations and were complemented by Raman spectroscopy and theoretical calculations. Of great importance is the Raman analysis, which corroborated n-doping of the nanocarbons due to the interactions with 1−4 when probed in the solid state. In solution, the situation is, however, quite different. Efficient charge separation was only observed for the graphene-based system NG/ 3.

Different water-soluble perylenediimides (PDIs) have been used to individualize and stabilize single-walled carbon nanotubes (SWCNTs) in aqueous media. A key feature of the PDIs is that they can be substituted at the bay positions via the addition of two and/or four bromines. This enables control over structural and electronic PDI characteristics, which prompted us to conduct comparative assays with focus on SWCNTs' chirality and charge transfer. Electrochemical, microscopic, and spectroscopic experiments were used to investigate the SWCNT chiral selectivity of PDIs, on the one hand, and charge-transfer reactions between SWCNTs and PDIs, on the other hand.

Herein, the microscopic and spectroscopic characterization of a novel non‐covalent electron donor−acceptor system, in which three different metalloporphyrins (1, 2, and 3) play the dual role of light harvester and electron donor with SWCNTs as electron acceptor, is described. To this end, microscopy, that is, atomic force microscopy (AFM) and transmission electron microscopy (TEM) corroborate the formation of 1‐SWCNT, 2‐SWCNT, and 3‐SWCNT. Spectroscopy by means of Raman, fluorescence, and transient absorption spectroscopy confirmed efficient charge‐transfer interaction from photoexcited metalloporphyrins to SWCNTs in the ground and excited state of 1‐SWCNT, 2‐SWCNT, and 3‐SWCNT. The complementary use of spectroelectrochemical and transient absorption measurements substantiates the formation of one‐electron oxidized metalloporphyrins after photoexcitation. Multiwavelength global analysis provides insights into the charge‐separation and recombination processes in 1‐SWCNT, 2‐SWCNT, and 3‐SWCNT upon photoexcitation. Notably, both the charge‐separation and recombination dynamics are fastest in 2‐SWCNT. Importantly, the strongest interactions in the steady‐state experiments are associated with the fastest excited state decay in the time‐resolved measurements.