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Various nanostructures of 5,10,15,20-tetrakis(4-carboxyl phenyl)-porphyrin (H2TCPP) can be easily synthesized by a surfactant-assisted self-assembly (SAS) method at different temperatures. When the DMF solution of porphyrin monomer was injected into cetyltimethylammonium bromide (CTAB) aqueous solution by a syringe, diverse H2TCPP nanostructures dependent on the different temperatures, including hollow nanospheres, solid nanospheres and nanospheres with holes, were successfully obtained. As a result, the suitable concentration of the CTAB aqueous solution used to form nanostructues of porphyrin ranges from 0.15 to 0.2 mM. The various morphologies of porphyrin nanostructures were characterized by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). UV-vis adsorption spectra showed that the micro-/nano-aggregate properties of porphyrin transformed from H-aggretates to J-aggregates during the process of self-assembly of porphyrin at different temperatures. Fluorescence spectra revealed a greater fluorescence quenching of various micro-/nano-aggregatess of porphyrin formed at different temperatures in aqueous solution, compared to the DMF solution of porphyrin monomer., (© 2013.)

A novel fluorescent nanoprobe with high sensitivity and selectivity for detection and imaging of the superoxide anion radical O(2)(·-) in living cells was designed and synthesized by a simple self-assembly method based on 2-chloro-1,3-dibenzothiazoline-cyclohexene (DBZTC) and Ag@SiO(2) core-shell nanoparticles., (This journal is © The Royal Society of Chemistry 2012)

Water soluble, thioglycolic acid (TGA) modified CdSe nanocrystals (NCs) have been prepared in aqueous media by the reaction between Cd2+ and NaHSe. Although initially these quantum dots (QDs) display photoluminescence (PL) with very low quantum yields (QY), upon prolonged exposure to ambient light, a strong PL enhancement by illumination is observed which leads to water soluble QDs with high luminescence. This result may have important application potential in biological or other fields. The primary reason for the luminescence enhancement is concluded to be the incorporation of sulfide ions from TGA into the lattice of CdSe NCs and the subsequent formation of alloy structures. Moreover, the CdSe/CdS core-shell structured QDs synthesized in aqueous solutions also consolidate this conclusion.

One-dimensional (1D) hierarchical nanostructures of ultralong layered K(x)MnO(2) (x < 0.3) bundles with diameters 50-100 nm and lengths up to 50-100 microm have been successfully prepared by a PEG-assisted hydrothermal method based on the reaction of KMnO(4) with 2-ethylhexanol. The obtained samples ascribe to the monoclinic phase and exhibit ferromagnetic behaviors below 32 K and paramagnetic behaviors above 32 K, which may make this system a promising base material for magnetic devices. A series of contrastive experiments have illustrated that 2-ethylhexanol, PEG 400, KOH, and reaction time play an important role in the synthesis of the nanobundles. A possible growth mechanism has been proposed.

Abstract: A facile hydrothermal approach based on n-nonyl alcohol mediated process has been developed to synthesize self-assembled Fe3O4 hierarchical nanostructures. The as-synthesized hierarchical nanostructured Fe3O4 could be easily transformed to γ-Fe2O3 and α-Fe2O3 without changing its original morphology by calcination in air. X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) were performed to investigate the evolution process of Fe3O4 hierarchical nanostructures. The growth mechanism of the as-prepared Fe3O4 nanostructure and the subsequently hierarchical nanostructures are suggested. The as-obtained iron oxide nanomaterials were used as adsorbent in water treatment, and were found an excellent ability to remove organic pollutants such as Orange II in waste water. [Copyright &y& Elsevier]