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.

Conductive polymer nanocomposites have found applications in advanced devices: organic light emission diodes, organic photovoltaics, electrochromic devices, and others.

Lyotropic liquid crystalline phases of an amphiphilic block copolymer are constructed and characterized in an ionic liquid with comparison of component and temperature effects.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are two kinds of emerging contaminants most studied in recent years. However, there is limited information about their combined toxicity to aquatic organisms. In the present study, the single and combined toxicity of PFOA and PFOS to zebrafish (Danio rerio) embryos were investigated. PFOS was more toxic than PFOA for the single toxicity. In four mixtures, PFOS and PFOA showed complex interactive effects that changed from additive to synergistic effect, then to antagonistic effect, and at last turnover to synergic effect again, with increased molar ratios of PFOS. Neither the concentration-addition model nor the independent-action model could predict the combined effects when strong interactive effects existed. Although the interactive effects of PFOS and PFOA affected their combined toxicity, the trend of mixture toxicity still showed an increase with increasing molar ratios of PFOS in the mixture.

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A new and simple method is used to control formation of gold nanoparticles in lyotropic liquid crystal. Triangular or hexagonal nano- and micro-plates can be obtained in PEO–PPO–PEO-based hexagonal liquid crystals after adding a small amount of cationic surfactant, CTAB. All plates are single crystals and mostly characterized by orientation along the [-111] direction. Their sizes are even longer than 10 μm. The selective adsorption of CTAB on certain crystallographic facets is the main point of supposed mechanism.

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