Single-crystalline gold nano- and microplates with triangular or hexagonal shapes are synthesized by reduction of HAuCl(4) in lyotropic liquid crystal (LLC) mainly made of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) block copolymers and water after adding a small amount of capping agents, cetyltrimethylammonium bromide (CTAB) or tetrabutylammonium bromide (TBAB). During the growth of such plates, capping agents play the crucial role. It is found that there is an optimal value of CTAB or TBAB concentration for producing microplates. The selective adsorption of CTAB or TBAB on certain crystallographic facets may be the key point of the supposed mechanism. Although LLC does not really act as a template, it provides an ordered structure confining CTAB as well as the nascent metal nuclei, which enhances the oriented attachment of nuclei and thus the consequent growth of single-crystal plates.

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We demonstrate the nanoscale p-type Bi2Te3 powder-based saturable absorber-induced passive mode-locking of the erbium-doped fiber laser (EDFL) with sub-picosecond pulsewidth. Such a nanoscale topological insulator powder is obtained by polishing the bulk p-type Bi2Te3 in a commercial thermoelectric cooler (TE cooler). This is then directly brushed onto the end-face of a single-mode fiber patchcord, to avoid any mis-connecting loss caused by laser beam divergence, which can result in a mode-locked pulsewidth of 436 fs in the self-amplitude modulation mode of a TE cooler. To further shorten the pulse, the soliton compression is operated by well-controlling the group delay dispersion and self-phase modulation, providing the passively mode-locked EDFL with a pulsewidth as short as 403 fs.

As a new dynamic density functional method, the mesoscopic dynamics (MesoDyn) is used to simulate the microphase separation of the binary mixture of tri-block copolymer P123 ((EO)20(PO)70(EO)20) and water. With a simple copolymer model, various aggregate structures of P123 in water including the micelle, hexagonal, and lamellar phases are produced, which can partly reproduce most experimental phase regions. The simulated phase ranges are more or less different from those established from experiment, especially at high polymer concentrations. This can be attributed to different phase mapping situations, that is, the constant shear used in simulation versus the varied external forces in experiment. The calculated trend for micelle size change in diluted region is co-incident well with previous observations in other Pluronic systems. The poly(propylene oxide) (PO) block amount is found to influence not only the aggregate morphology but also its formation rate in solution. Obtained results indicate that the mesoscopic simulation is a valuable tool to supplement the experimental study on aggregates formation.

Self-assembly vesicles have been made from a cyclodextrin (CD) supramolecular complex, which is cooperatively formed with natural beta-CD, 1-naphthylammonium chloride (NA), and sodium bis(2-ethyl-1-hexyl)sulfosuccinate (AOT) by weak noncovalent interactions. In the complex structure, a NA molecule is included inside a beta-CD molecule while it is coupled with an AOT molecule on one side. The supramolecular structure and morphology of the vesicles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. The mechanism of vesicle formation and transition is discussed along with the data obtained from induced circular dichroism (ICD) and UV/visible spectroscopy, polarized optical microscopy (POM), and (1)H NMR spectroscopy. Both the fabrication and the transition of vesicles are controlled by the inclusion equilibria and the cooperative binding of noncovalent interactions, which include the "key-lock" principle, electrostatic interactions, pi-pi stacking, and amphiphilic hydrophobic association.

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Positively charged silver nanoparticles capped by cetyltrimethyl ammonium bromide (CTAB) are prepared in aqueous solution. The structure of capping agents on Ag particles is systematically characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). It suggests that CTAB molecules form a bilayer shell on Ag surface with a 1:5 rough ratio of inner/outer molecules.

The protection behaviors of two new phosphate self-assembled films, triphenyl phosphate (TPP) and bis-(2-ethylhexyl) phosphate (BEP), against the corrosion of iron in 0.5 M H 2 SO 4 were investigated using the electrochemical impedance spectroscopy (EIS), polarization curves, Fourier transform infrared (FT-IR) spectroscopy, and molecular simulations. The polarization curves showed a decrease in corrosion current density for the electrode covered with phosphates. Impedance spectra demonstrated that the charge-transfer resistance (R ct ) of the electrode covered with phosphate was greater than that of the naked iron electrode. Results show that TPP molecules can adsorb on the iron surface quickly in a short time and that the coverage (θ) of the film will get to the maximum in 4 h. Subsequently, the amount of TPP molecules on the iron surface remains constant, while θ of BEP on the iron surface increases with the immersion time in 24 h. FT-IR spectroscopy was applied for the surface analysis and confirmed the adsorption of phosphates on the iron surface by monitoring the functional group peaks of the compounds. Molecular simulations were performed to illustrate the adsorption process at a molecule level and to provide some theoretical information for our experiment.