Controllable Fabrication of Layer Structures by Self-Assembled Perylene Derivative

The compound of perylene-3,4,9,10-tetracarboxylic acid (PTCA) has been synthesized and characterized. By varying the concentration, it can be used to modulate the supramolecular self-assembly morphologies. Atom force microscopy (AFM) images show that the nano-layer structure will be obtained in relatively high concentration. This structure mainly depends on the intermolecular hydrogen-bonding and π–π stacking interactions.

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Fabrication of Highly Ordered Two-Dimensional Graphene Arrays on Patterned Substrate

Materials Science Forum ◽

10.4028/www.scientific.net/msf.809-810.231 ◽

2014 ◽

Vol 809-810 ◽

pp. 231-236

Author(s):

Meng Jie Chang ◽

Jun Liu ◽

Ying Li

Keyword(s):

Self Assembly ◽

Two Dimensional ◽

High Concentration ◽

Contact Printing ◽

Patterned Substrate ◽

Force Microscopy ◽

Saturated Water ◽

Straightforward Method ◽

Atom Force Microscopy ◽

Wetting Property

We report a facial and straightforward method to fabricate highly ordered two-dimensional graphene arrays. A monolayer molecule pattern with alternative hydrophilic/hydrophobic wetting property was first formed by using micro-contact printing (μCP) and self-assembly techniques. Water droplets were condensed on the hydrophilic areas under saturated water atmosphere, which could be used to construct the ordered graphene arrays. The optical microscopy and atom force microscopy results indicate that ring and porous arrays of graphene can be obtained with low and high concentration of graphene solutions, respectively. Without the water droplet template, graphene patterns with square structure were produced.

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Chiral anionic layers in tartramide spiroborate salts and variable solvation for [NR 4][B(TarNH2)2] (R = Et, Pr or Bu)

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229620008384 ◽

2020 ◽

Vol 76 (7) ◽

pp. 695-705

Author(s):

Aristyo Soecipto ◽

Lawrence W.-Y. Wong ◽

Herman H.-Y. Sung ◽

Ian D. Williams

Keyword(s):

Hydrogen Bonding ◽

Self Assembly ◽

Interfacial Area ◽

Intermolecular Hydrogen Bonding ◽

Two Dimensional ◽

Salt Hydrate ◽

Anion Layer ◽

Cation Layer ◽

Layer Structures ◽

Solvent Molecules

The spiroborate anion, namely, 2,3,7,8-tetracarboxamido-1,4,6,9-tetraoxa-5λ4-boraspiro[4.4]nonane, [B(TarNH2)2]−, derived from the diol L-tartramide TarNH2, [CH(O)(CONH2)]2, shows a novel self-assembly into two-dimensional (2D) layer structures in its salts with alkylammonium cations, [NR 4]+ (R = Et, Pr and Bu), and sparteinium, [HSpa]+, in which the cations and anions are segregated. The structures of four such salts are reported, namely, the tetrapropylazanium salt, C12H28N+·C8H12BN4O8 −, the tetraethylazanium salt hydrate, C8H20N+·C8H12BN4O8 −·6.375H2O, the tetrabutylazanium salt as the ethanol monosolvate hemihydrate, C16H36N+·C8H12BN4O8 −·C2H5OH·0.5H2O, and the sparteinium (7-aza-15-azoniatetracyclo[7.7.1.02,7.010,15]heptadecane) salt as the ethanol monosolvate, C15H27N2 +·C8H12BN4O8 −·C2H5OH. The 2D anion layers have preserved intermolecular hydrogen bonding between the amide groups and a typical metric repeat of around 10 × 15 Å. The constraint of matching the interfacial area organizes the cations into quite different solvated arrangements, i.e. the [NEt4] salt is highly hydrated with around 6.5H2O per cation, the [NPr4] salt apparently has a good metric match to the anion layer and is unsolvated, whilst the [NBu4] salt is intermediate and has EtOH and H2O in its cation layer, which is similar to the arrangement for the chiral [HSpa]+ cation. This family of salts shows highly organized chiral space and offers potential for the resolution of both chiral cations and neutral chiral solvent molecules.

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SWNT-DNA and SWNT-polyC Hybrids: AFM Study and Computer Modeling

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.18214 ◽

2008 ◽

Vol 8 (3) ◽

pp. 1473-1480 ◽

Cited By ~ 16

Author(s):

M. V. Karachevtsev ◽

O. S. Lytvyn ◽

S. G. Stepanian ◽

V. S. Leontiev ◽

L. Adamowicz ◽

...

Keyword(s):

Computer Modeling ◽

Interaction Energy ◽

Intermolecular Interactions ◽

Self Assembly ◽

Polymeric Coating ◽

Tube Surface ◽

Force Microscopy ◽

Single Walled Nanotubes ◽

Double Stranded Dna ◽

Atom Force Microscopy

Hybrids of carbon single-walled nanotubes (SWNT) with fragmented single or double-stranded DNA (fss- or fds-DNA) or polyC were studied by Atom Force Microscopy (AFM) and computer modeling. It was found that fragments of the polymer wrap in several layers around the nanotube, forming a strand-like spindle. In contrast to the fss-DNA, the fds-DNA also forms compact structures near the tube surface due to the formation of self-assembly structures consisting of a few DNA fragments. The hybrids of SWNT with wrapped single-, double- or triple strands of the biopolymer were simulated, and it was shown that such structures are stable. To explain the reason of multi-layer polymeric coating of the nanotube surface, the energy of the intermolecular interactions between different components of polyC was calculated at the MP2/6-31++G** level as well as the interaction energy in the SWNT-cytosine complex.

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Clathrin-Inspired Coating and Stabilization of Liposomes by DNA Self-Assembly

10.26434/chemrxiv.8859017.v1 ◽

2019 ◽

Author(s):

Kevin N. Baumann ◽

Luca Piantanida ◽

Javier García-Nafría ◽

Diana Sobota ◽

Kislon Voïtchovsky ◽

...

Keyword(s):

Self Assembly ◽

Mechanical Stability ◽

Lipid Vesicles ◽

The Self ◽

Force Microscopy ◽

Atomic Force ◽

Cryo Electron Microscopy ◽

Further Development ◽

Liposome Surface ◽

Dna Coating

The self-assembly of the protein clathrin on biological membranes facilitates essential processes of endocytosis in biological systems and has provided a source of inspiration for materials design by the highly ordered structural appearance. By mimicking the architecture of clathrin self-assemblies to coat liposomes with biomaterials, new classes of hybrid carriers can be derived. Here we present a method for fabricating DNA-coated liposomes by hydrophobically anchoring and subsequently growing a DNA network on the liposome surface which structurally mimics clathrin assemblies. Dynamic light scattering (DLS), ζ-potential and cryo-electron microscopy (cryo-EM) measurements independently demonstrate successful DNA coating. Nanomechanical measurements conducted with atomic force microscopy (AFM) show that the DNA coating enhances the mechanical stability of the liposomes relative to uncoated ones. Furthermore, we provide the possibility to reverse the coating process by triggering the disassembly of the DNA coating through a toehold-mediated displacement reaction. Our results describe a straightforward, versatile, and reversible approach for coating and stabilizing lipid vesicles by an interlaced DNA network. This method has potential for further development towards the ordered arrangement of tailored functionalities on the surfaces of liposomes and for applications as hybrid nanocarrier.

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Fabrication of Piezoelectric ZnO Nanowires Energy Harvester on Flexible Substrate Coated with Various Seed Layer Structures

Nanomaterials ◽

10.3390/nano11061433 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1433

Author(s):

Taoufik Slimani Tlemcani ◽

Camille Justeau ◽

Kevin Nadaud ◽

Daniel Alquier ◽

Guylaine Poulin-Vittrant

Keyword(s):

Seed Layer ◽

Layer Structure ◽

Mechanical Energy ◽

Flexible Substrate ◽

Average Power ◽

Electrical Characterization ◽

Zno Nanowires ◽

Device Structure ◽

Layer Structures ◽

Electrical Output

Flexible piezoelectric nanogenerators (PENGs) are very attractive for mechanical energy harvesting due to their high potential for realizing self-powered sensors and low-power electronics. In this paper, a PENG that is based on zinc oxide (ZnO) nanowires (NWs) is fabricated on flexible and transparent Polydimethylsiloxane (PDMS) substrate. The ZnO NWs were deposited on two different seed layer structures, i.e., gold (Au)/ZnO and tin-doped indium-oxide (ITO)/ZnO, using hydrothermal synthesis. Along with the structural and morphological analyses of ZnO NWs, the electrical characterization was also investigated for ZnO NWs-based flexible PENGs. In order to evaluate the suitability of the PENG device structure, the electrical output performance was studied. By applying a periodic mechanical force of 3 N, the ZnO NWs-based flexible PENG generated a maximum root mean square (RMS) voltage and average power of 2.7 V and 64 nW, respectively. Moreover, the comparison between the fabricated device performances shows that a higher electrical output can be obtained when ITO/ZnO seed layer structure is adopted. The proposed ZnO NWs-based PENG structure can provide a flexible and cost-effective device for supplying portable electronics.

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Restricted Rotational Motion of InterlayerWaterMolecules in Vanadium Pentoxide Hydrate, V2O5·n D2O, as Studied by Deuterium NMR

Zeitschrift für Naturforschung A ◽

10.1515/zna-2002-6-723 ◽

2002 ◽

Vol 57 (6-7) ◽

pp. 419-424 ◽

Cited By ~ 6

Author(s):

Sadamu Takeda ◽

Yuko Gotoh ◽

Goro Maruta ◽

Shuichi Takahara ◽

Shigeharu Kittaka

Keyword(s):

Double Layer ◽

Vanadium Pentoxide ◽

Rotational Motion ◽

Interlayer Space ◽

Layer Structure ◽

Bond Distance ◽

Adsorbed Water ◽

Deuterium Nmr ◽

Water Molecules ◽

Layer Structures

The rotational behavior of the interlayer water molecules of deuterated vanadium pentoxide hydrate, V2O5.nD2O, was studied by solid-state deuterium NMR for the mono- and double-layer structures of the adsorbed water molecules. The rotational motion was anisotropic even at 355 K for both the mono- and double-layer structures. The 180° flipping motion about the C2-symmetry axis of the water molecule and the rotation around the figure axis, which makes an angle Ɵ with the C2-axis, occurred with the activation energy of (34±4) and (49±6) kJmol-1, respectively. The activation energies were almost independent of the mono- and double-layer structures of the water molecules, but the angle Ɵ made by the two axes varied from 33° for the monolayer to 25° for the double-layer at 230 K. The angle started to decrease above 250 K (e. g. the angle was 17 at 355 K for the double-layer structure). The results indicate that the average orientation of the water molecules in the two dimensional interlayer space depends on the layer structure and on the temperature. From the deuterium NMR spectrum at 130 K, the quadrupole coupling constant e2Qq/h = 240 kHz and the asymmetry parameter η= 0.12 were deduced. These values indicate the average hydrogen bond distance R(O H) = 2.0 Å for the D2O molecules in the 2D-interlayer space

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Controllable fabrication of lotus-leaf-like superhydrophobic surface on copper foil by self-assembly

Applied Physics A ◽

10.1007/s00339-014-8472-6 ◽

2014 ◽

Vol 116 (4) ◽

pp. 1613-1620 ◽

Cited By ~ 15

Author(s):

Zhiqing Yuan ◽

Xian Wang ◽

Jiping Bin ◽

Menglei Wang ◽

Chaoyi Peng ◽

...

Keyword(s):

Self Assembly ◽

Superhydrophobic Surface ◽

Copper Foil ◽

Lotus Leaf ◽

Controllable Fabrication

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Characterization of the porous nature of a phthalocyanine derivative with axial ligation designed to prevent aggregation

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424610002173 ◽

2010 ◽

Vol 14 (05) ◽

pp. 389-396

Author(s):

Carl A. Barker ◽

Alan Massey ◽

Aidan Rhodes ◽

Martin R. Bryce ◽

Ritu Kataky

Keyword(s):

Force Microscopy ◽

Selective Transport ◽

Electrode Surfaces ◽

Axial Ligation ◽

Nanoporous Films ◽

Atom Force Microscopy ◽

Solvent Cast ◽

Complementary Techniques

Judiciously designed phthalocyanines (Pcs), such as silicon-Pc bis(3,5-diphenyl)benzoate (1c), with axial substituents which prevent aggregation, can self-assemble to form ordered nanoporous films on electrode surfaces. In this paper, complementary techniques such as Scanning Kelvin Nanoprobe (SKN) microscopy, Atom Force Microscopy (AFM) and electrochemical measurements are used to demonstrate that films formed by silicon-Pc bis(3,5-diphenyl)benzoate allow size- and charge- selective transport of probe molecules through well-defined intermolecular cavities. In contrast, the analogs silicon-Pc bis(4-tert-butylbenzoate) (1a) and silicon-Pc bis(3-thienyl)acetate (1b) have different film morphologies when solvent-cast in the same manner and block the electrode surface. The role of the different axial substituents in orienting the molecules on the substrate is discussed.

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