Substituent Effects of Porphyrins on Structures and Photophysical Properties of Amphiphilic Porphyrin Aggregates

Abstract

Substituent effects of porphyrin on the structures and photophysical properties of the J-aggregates of protonated 5-(4-alkoxyphenyl)-10,15,20-tris(4-sulfonatophenyl)porphyrin have been examined for the first time. Selective formation of the porphyrin J-aggregate was attained when suitable length of the alkoxy group was employed for the amphiphilic porphyrin. Namely, a regular leaflike structure was observed for the J-aggregates of protonated 5-(4-octyloxyphenyl)-10,15,20-tris(4-sulfonatophenyl)porphyrin, which was consistent with the results obtained by using the UV-visible absorption and dynamic light-scattering measurements. A bilayer structure in which the hydrophobic alkoxyl groups facing inside the bilayer are interdigitated to each other, whereas the hydrophilic porphyrin moieties are exposed outside, was proposed to explain the unique porphyrin J-aggregate. Fast energy migration and efficient quenching by defect site in the J-aggregates were suggested to rationalize the short lifetimes of the excited J-aggregates.

Structures Self‐Assembled from Anionic Graphene and Cationic Manganese Porphyrin: Characterization and Application in Artificial Photosynthesis

“…The UV/Vis spectra of the diluted aqueous CGO solutions showed a broad peak with λ max at around 223 nm and a shoulder at around 290 nm. [45] The complex, branched structure of the graphene-porphyrin species extends to distances in the micrometer range (inset of Figure 1, D). Samples of the methanolic solutions obtained during this period were used to prepare films of CGO-MnTMPyP, the morphologies of which were examined by SEM and TEM and compared with those of CGO.…”

A Molecular Template Designed by the Modification of a Helix-Forming β-1,3-Glucan Polysaccharide To Fabricate One-Dimensional Nanostructures

“…The UV-vis spectrum of H 4 TPPS 2-in the absence of CUR-N þ shows characteristic peaks at 435 nm (Soret band) and 645 nm (Q band) arising from monomeric H 4 TPPS 2-, as shown in Figure 5B. Upon gradual addition of CUR-N þ , both Soret and Q bands are red-shifted to 493 and 707 nm, respectively, [32][33][34][35] which are sometimes ascribed to new bands. 39 These spectral changes are attributed to the formation of the J-aggregate and almost saturated at [trimethylammonium]/[sulfonate] = 0.5, indicating that two anionic sulfonate groups in one H 4 TPPS 2-molecule are neutralized by cationic trimethylammonium groups in CUR-N þ .…”

Bio‐Inspired Phosphole‐Lipids: From Highly Fluorescent Organogels to Mechanically Responsive FRET

“…[10] But more importantly, the FRET efficiency is highly dependent on the donoracceptor distance, which makes such intermolecular process very useful for the sensing of external stimuli, particularly in the application toward mechanical responses. [10] But more importantly, the FRET efficiency is highly dependent on the donoracceptor distance, which makes such intermolecular process very useful for the sensing of external stimuli, particularly in the application toward mechanical responses.…”