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.