Self-Assembled Nano-Structures of Sandwich-Type Mixed (Phthalocyaninato)(porphyrinato) Rear Earth Complexes. Effect of Porphyrin-Phthalocyanine Ligands on Tuning the Inter-Molecular Interaction

2009 ◽  
Vol 79-82 ◽  
pp. 341-344 ◽  
Author(s):  
Li Na Chen ◽  
Yan Li Chen ◽  
Pei Hua Zhu ◽  
Guo Xin Sun ◽  
Hong Yan Wang ◽  
...  

phthalocyanine, porphyrin, sandwich rare earth complex, nanostructure, self-assembly. Abstract. Three novel sandwich-type mixed (phthalocyaninato)(porphyrinato) rear earth complexes, namely Ce(DPP)(Pc)(1), Sm2(DPP)(Pc)2(2) and Sm2(DPP)2(Pc)(3) [Pc = dianion of phthalocyanine, DPP= dianion of 5,15-di(phenyl)porphyrin], have been fabricated into nano-assemblies onto the SiO2 surface by a surface assisted solvent-vapor annealing method. The effect of the number of porphyrin and phthalocyanine ligands on the morphology of self-assembled nanostructures of these double- and triple-decker complexes has been systematically studied. Competition and cooperation between the inter-molecular - interaction, van der Waals, and metal-ligand coordination for different compounds results in nanostructures with different morphology from approximately spherical shape with average size of ~300 nm and ~400 nm for 1 and 2, respectively, nano-rods with aspect ratio (length over width) around 5 for 3, which were characterized by electronic absorption, X-ray diffraction (XRD), and atomic force microscopy (AFM). Electronic absorption spectroscopic results reveal the formation of J-aggregates in the nano-structures and suggest the increasing - interaction in the order of 3, 1, to 2. Examination by XRD reveal that in the nanostructures of compounds 1-3, a dimeric supramolecular structure was formed through an intermolecular - interaction and/or van der Waals between two sandwich-type molecules, which as the building block self-assembles into the target nanostructures.

2020 ◽  
Author(s):  
Daniel B. Straus ◽  
Robert J. Cava

The design of new chiral materials usually requires stereoselective organic synthesis to create molecules with chiral centers. Less commonly, achiral molecules can self-assemble into chiral materials, despite the absence of intrinsic molecular chirality. Here, we demonstrate the assembly of high-symmetry molecules into a chiral van der Waals structure by synthesizing crystals of C<sub>60</sub>(SnI<sub>4</sub>)<sub>2</sub> from icosahedral buckminsterfullerene (C<sub>60</sub>) and tetrahedral SnI4 molecules through spontaneous self-assembly. The SnI<sub>4</sub> tetrahedra template the Sn atoms into a chiral cubic three-connected net of the SrSi<sub>2</sub> type that is held together by van der Waals forces. Our results represent the remarkable emergence of a self-assembled chiral material from two of the most highly symmetric molecules, demonstrating that almost any molecular, nanocrystalline, or engineered precursor can be considered when designing chiral assemblies.


2019 ◽  
Vol 33 (14n15) ◽  
pp. 1940038
Author(s):  
Gyounglyul Jo ◽  
Solip Choi ◽  
Jae Won Jeong ◽  
Gyun Taek Lim ◽  
Jaehan Jung ◽  
...  

A facile solution treatment strategy for controlling the microstructure of conjugated polymers using a non-solvent vapor is introduced. The content of well-ordered poly(3-hexylthiophene) (P3HT) aggregates in solution was precisely controlled by varying the non-solvent vapor exposure time. P3HT chains were self-assembled upon exposure to the non-solvent vapor to minimize the unfavorable interactions with the non-solvent molecules. The effect of solvent vapor on the molecular ordering and morphologies of P3HT films was investigated by UV-Vis spectroscopy, atomic force microscopy, and polarized optical microscopy. These studies reveal that the self-assembled P3HT aggregates have well-ordered nanofibrillar structures formed via [Formula: see text]–[Formula: see text] stacking. This strategy paves the way toward fabricating well-ordered polymeric structures, especially in the field of opto-electronic applications including FETs, LEDs, and lasers, where proper alignment or molecular assembly is in great demand.


2020 ◽  
Author(s):  
Daniel B. Straus ◽  
Robert J. Cava

The design of new chiral materials usually requires stereoselective organic synthesis to create molecules with chiral centers. Less commonly, achiral molecules can self-assemble into chiral materials, despite the absence of intrinsic molecular chirality. Here, we demonstrate the assembly of high-symmetry molecules into a chiral van der Waals structure by synthesizing crystals of C<sub>60</sub>(SnI<sub>4</sub>)<sub>2</sub> from icosahedral buckminsterfullerene (C<sub>60</sub>) and tetrahedral SnI<sub>4</sub> molecules through spontaneous self-assembly. Our results represent the remarkable emergence of chirality from the self-assembly of two of the most highly symmetric molecules, demonstrating that almost any molecular precursor can be considered when designing chiral assemblies.


2020 ◽  
Author(s):  
Daniel B. Straus ◽  
Robert J. Cava

The design of new chiral materials usually requires stereoselective organic synthesis to create molecules with chiral centers. Less commonly, achiral molecules can self-assemble into chiral materials, despite the absence of intrinsic molecular chirality. Here, we demonstrate the assembly of high-symmetry molecules into a chiral van der Waals structure by synthesizing crystals of C<sub>60</sub>(SnI<sub>4</sub>)<sub>2</sub> from icosahedral buckminsterfullerene (C<sub>60</sub>) and tetrahedral SnI4 molecules through spontaneous self-assembly. The SnI<sub>4</sub> tetrahedra template the Sn atoms into a chiral cubic three-connected net of the SrSi<sub>2</sub> type that is held together by van der Waals forces. Our results represent the remarkable emergence of a self-assembled chiral material from two of the most highly symmetric molecules, demonstrating that almost any molecular, nanocrystalline, or engineered precursor can be considered when designing chiral assemblies.


CrystEngComm ◽  
2019 ◽  
Vol 21 (4) ◽  
pp. 602-615 ◽  
Author(s):  
Mohadeseh A. Baboli ◽  
Michael A. Slocum ◽  
Hyun Kum ◽  
Thomas S. Wilhelm ◽  
Stephen J. Polly ◽  
...  

Self-assembly of InAs nanowire arrays with highest reported aspect ratios and number density by van der Waals epitaxy on graphene is presented.


MRS Advances ◽  
2020 ◽  
Vol 5 (64) ◽  
pp. 3507-3520
Author(s):  
Chunhui Dai ◽  
Kriti Agarwal ◽  
Jeong-Hyun Cho

AbstractNanoscale self-assembly, as a technique to transform two-dimensional (2D) planar patterns into three-dimensional (3D) nanoscale architectures, has achieved tremendous success in the past decade. However, an assembly process at nanoscale is easily affected by small unavoidable variations in sample conditions and reaction environment, resulting in a low yield. Recently, in-situ monitored self-assembly based on ion and electron irradiation has stood out as a promising candidate to overcome this limitation. The usage of ion and electron beam allows stress generation and real-time observation simultaneously, which significantly enhances the controllability of self-assembly. This enables the realization of various complex 3D nanostructures with a high yield. The additional dimension of the self-assembled 3D nanostructures opens the possibility to explore novel properties that cannot be demonstrated in 2D planar patterns. Here, we present a rapid review on the recent achievements and challenges in nanoscale self-assembly using electron and ion beam techniques, followed by a discussion of the novel optical properties achieved in the self-assembled 3D nanostructures.


2021 ◽  
Vol 11 (7) ◽  
pp. 3254
Author(s):  
Marco Pisco ◽  
Francesco Galeotti

The realization of advanced optical fiber probes demands the integration of materials and structures on optical fibers with micro- and nanoscale definition. Although researchers often choose complex nanofabrication tools to implement their designs, the migration from proof-of-principle devices to mass production lab-on-fiber devices requires the development of sustainable and reliable technology for cost-effective production. To make it possible, continuous efforts are devoted to applying bottom-up nanofabrication based on self-assembly to decorate the optical fiber with highly ordered photonic structures. The main challenges still pertain to “order” attainment and the limited number of implementable geometries. In this review, we try to shed light on the importance of self-assembled ordered patterns for lab-on-fiber technology. After a brief presentation of the light manipulation possibilities concerned with ordered structures, and of the new prospects offered by aperiodically ordered structures, we briefly recall how the bottom-up approach can be applied to create ordered patterns on the optical fiber. Then, we present un-attempted methodologies, which can enlarge the set of achievable structures, and can potentially improve the yielding rate in finely ordered self-assembled optical fiber probes by eliminating undesired defects and increasing the order by post-processing treatments. Finally, we discuss the available tools to quantify the degree of order in the obtained photonic structures, by suggesting the use of key performance figures of merit in order to systematically evaluate to what extent the pattern is really “ordered”. We hope such a collection of articles and discussion herein could inspire new directions and hint at best practices to fully exploit the benefits inherent to self-organization phenomena leading to ordered systems.


2009 ◽  
Vol 143 ◽  
pp. 345 ◽  
Author(s):  
Aurelie M. Brizard ◽  
Marc C. A. Stuart ◽  
Jan H. van Esch

Soft Matter ◽  
2021 ◽  
Author(s):  
Jiawei Lu ◽  
Xiangyu Bu ◽  
Xinghua Zhang ◽  
Bing Liu

The shapes of colloidal particles are crucial to the self-assembled superstructures. Understanding the relationship between the shapes of building blocks and the resulting crystal structures is an important fundamental question....


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