Nanoscale Crystalline Sheets and Vesicles Assembled from Nonplanar Cyclic π -Conjugated Molecules

Abstract

<jats:p>A fundamental challenge in chemistry and materials science is to create new carbon nanomaterials by assembling structurally unique carbon building blocks, such as nonplanar <jats:italic>π</jats:italic>-conjugated cyclic molecules. However, self-assembly of such cyclic <jats:italic>π</jats:italic>-molecules to form organized nanostructures has been rarely explored despite intensive studies on their chemical synthesis. Here we synthesized a family of new cycloparaphenylenes and found that these fully hydrophobic and nonplanar cyclic <jats:italic>π</jats:italic>-molecules could self-assemble into structurally distinct two-dimensional crystalline multilayer nanosheets. Moreover, these crystalline multilayer nanosheets could overcome inherent rigidity to curve into closed crystalline vesicles in solution. These supramolecular assemblies show that the cyclic molecular scaffolds are homogeneously arranged on the surface of nanosheets and vesicles with their molecular isotropic x-y plane standing obliquely on the surface. These supramolecular architectures that combined exact crystalline order, orientation-specific arrangement of <jats:italic>π</jats:italic>-conjugated cycles, controllable morphology, uniform molecular pore, superior florescence quench ability, and photoluminescence are expected to give rise to a new class of functional materials displaying unique photonic, electronic, and biological functions.</jats:p>

Self-Assembly of Crystalline Vesicles from Nonplanar π-Conjugated Nanocycles

“…The synthetic route and characterization of the four CPPs are described in detail by the method we reported earlier. 37 Except for the pristine [8] CPP, the other three were [8]CPP-based compounds, which were dual-nature molecules. The pyrene-modified CPP had both cyclic and planar π-conjugated structures in its structure, and tetraphenylethene (TPE)-functionalized CPP was incorporated with both cyclic and nonplanar structures, whereas carboxyl-modified CPP possessed both hydrophilic and hydrophobic moieties in the molecule.…”

“…In our previous study, in the CPP self-organized two-dimensional structure, the CPP cyclic molecules are not arranged flatly on the plane but obliquely at a specific angle of approximately 67-68°. 37 This kind of molecular packing pattern is instrumental in adopting a herringbone packing structure and the formation of multilayer structure in the wall of vesicles. In fact, multilayer structures were observed on the wall of the CPP vesicles.…”

Facile Synthesis of Peptide-Conjugated Gold Nanoclusters with Different Lengths

“…Gold nanoparticles, particularly gold nanospheres [1][2][3][4][5][6][7][8] (Au NSs, size < 200 nm) and gold nanoclusters [9][10][11][12][13][14][15][16][17] (Au NCs, size < 2 nm), have received growing attention in recent years because of their excellent optical and electronic properties [18][19][20]. Many biomoleculeconjugated Au NSs have been prepared, such as peptide, protein, and DNA, which have a potential use in many biomedical and biosensing applications [21][22][23][24][25][26][27][28][29].…”