No abstract

Functional porphyrins have attracted intense attention due to their remarkably high extinction coefficients in the visible region and potential for optical and energy‐related applications. Two new routes to functionalised SWNTs have been established using a bulky ZnII‐porphyrin featuring thiolate groups at the periphery. We probed the optical properties of this zinc(II)‐substituted, bulky aryl porphyrin and those of the corresponding new nano‐composites with single walled carbon nanotube (SWNTs) and coronene, as a model for graphene. We report hereby on: i) the supramolecular interactions between the pristine SWNTs and ZnII‐porphyrin by virtue of π–π stacking, and ii) a novel covalent binding strategy based on the Bingel reaction. The functional porphyrins used acted as dispersing agent for the SWNTs and the resulting nanohybrids showed improved dispersibility in common organic solvents. The synthesized hybrid materials were probed by various characterisation techniques, leading to the prediction that supramolecular polymerisation and host–guest functionalities control the fluorescence emission intensity and fluorescence lifetime properties. For the first time, XPS studies highlighted the differences in covalent versus non‐covalent attachments of functional metalloporphyrins to SWNTs. Gas‐phase DFT calculations indicated that the ZnII‐porphyrin interacts non‐covalently with SWNTs to form a donor–acceptor complex. The covalent attachment of the porphyrin chromophore to the surface of SWNTs affects the absorption and emission properties of the hybrid system to a greater extent than in the case of the supramolecular functionalisation of the SWNTs. This represents a synthetic challenge as well as an opportunity in the design of functional nanohybrids for future sensing and optoelectronic applications.

Design and synthesis of a novel porphyrin‐based nanohybrid, whereby the entire surface of GO is modified via supramolecular assembly, is reported by S. I. Pascu and co‐workers on page 687. The Zn(II)‐porphyrin@GO nanohybrid forms stable dispersions in ethanol, likely containing free and bound Zn(II)‐porphyrin in a dynamic exchange. New opportunities for using uniform dispersions of tailor‐made nanohybrids incorporating GO within layered materials are opened up.

As a primary goal, this review highlights the role of supramolecular interactions in the assembly of new sustainable materials incorporating functional porphyrins and carbon nanoplatforms as building blocks for photovoltaics advancements.

Stimulated emission depletion (STED) super‐resolution imaging and multiphoton fluorescence lifetime imaging techniques are used to image the aggregation of ZnII porphyrin arrays onto flat and conductive, as well as insulating, surfaces. New synthetic routes using directed‐ as well as self‐assembling methods of new, luminescent hybrids incorporating these functional porphyrins and pristine single‐walled carbon nanotubes (SWNTs) are reported. Multi‐domain imaging and spectroscopy techniques shed light on the potential implications of the covalent and supramolecular functionalization approaches in solution, dispersion, on surfaces and in the solid state. For more information, see the Full Paper by S. I. Pascu et al. on page 9772 ff.