Formation and applications of stable 10 nm to 500 nm supramolecular porphyrinic materials

Abstract

Nanoscaled materials of organic dyes are of interest for a variety of potential applications because of the rich photonic properties that this class of molecules can impart. One mode to form such nanoscaled materials is via self‐organization and self‐assembly, using reasonably well understood methods in supramolecular chemistry. But there are inherent complexities that arise from the use of organic‐based supramolecular materials, including stability toward dioxygen, structural stability, and nanoarchitectures that may change with environmental conditions. Porphyrinoids have rich photonic properties yet are remarkably stable, have a rigid core, are readily functionalized, and metalation of the macrocycle can impart a plethora of optical, electronic, and magnetic properties. While there are many <10 nm porphyrinic assemblies, which may or may not self‐organize into crystals, there is a paucity of 10–500 nm porphyrinic materials that can be isolated and stored. A variety of strategies towards the latter nanoscopic porphyrinic materials are discussed in terms of design, construction, and nanoarchitecture. The hierarchical structures include colloids, nanorods, nanotubes, nanorings, and nano‐crystalline materials. This prolegomenon emphasizes the supramolecular chemistry, structure‐stability, and structure‐function relationships. The goal herein is to examine general trends and delineate general principles.

Liquid-crystalline phthalocyanine-based nanostructures

“…The interest in this class of compounds is deter mined by the peculiarity of the electronic structure of the aromatic system of phthalocyanine, which is as fol lows: the aromatic core in the phthalocyanine molecule is planar and sufficiently large (about 2 nm 2 ) [1]. Intro ducing additional nitrogen atoms makes the interac tions between the neighboring macrorings in columns stronger, which results in the larger rigidity of the Pc columns and the whole system [28].…”

“…When substituted phthalocyanines are used, there appears a possibility of extending the delocalized π electron system of the macroring, which results in more substantial structuring of the supramolecular ensemble [1]. As a result, Pc based mesogens with a noticeable thermal stability can be produced.…”

“…When materials based on mesomorphic phthalocyanines are applied to a surface, nanostructures that have interesting anisotro pic electrophysical properties are formed. Interest in the chemistry of mesomorphic phthalocyanines increases from year to year, and more than a thousand patents concerning phthalocyanines are granted every year [1].…”

Surface Morphology of Fe(III)-Porphyrin Thin Layers as Characterized by Atomic Force Microscopy

“…A formation of nanometer orde (10-500 nm) discrete material is a key issue for a various application technology in the future [29]. A discrete surface morphology of zinc porphyrin has been reported that can be controlled by varying the concentration as well as deposition parameters [30].…”

Synthesis and Spectroscopic Studies of Zirconium(IV) Porphyrins with Acetylacetonate and Phenolates at Axial Positions

“…The metal ions in these complexes are oxophilic; thus, the preference for carboxylate or other oxygen-bearing anionic ligands. Zr(IV) has an electron configuration of [Kr]4f 14 , is closed shell metal ion and Because of the lack of functional groups on the porphyrin moieties, there is a paucity of supramolecular materials with designed, hierarchical structures [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] containing Zr(Por). The key entry to the organometallic zirconium porphyrin complexes would be Zr-(Porphyrin)Cl 2 , analogous to ZrCp 2 Cl 2 .…”