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A systematic shape variation of zinc blende CdSe nanocrystals is demonstrated in a modified organometallic approach, in which distinct shapes of cube-shaped, sphere-shaped, tetrahedron-shaped and branched CdSe nanocrystals with high yield and good uniformity are obtained. The wide variation of shapes has provided important information about the growth of CdSe nanocrystals and it has helped in the shape-controlled synthesis of other nanocrystals that are bound with uniform crystal planes.

A near-neutral pH near-infrared (NIR) fluorescent probe using a fluorophore-spacer-receptor molecular framework that can modulate the fluorescence emission intensity through a fast photoinduced electron-transfer process is developed. The real-time imaging of cellular pH and the detection of pH in situ is achieved in living HepG2 and HL-7702 cells by this probe.

A general strategy is described for the synthesis of mesoporous materials by using artificial atoms as uniform building blocks to construct ordered mesostructures. This new approach for the synthesis of Ag, [Ag.sub.2]S and [Ag.sub.2]Se nanoparticles is shown to be efficient, economical and easy to scale up in industrial production.

A metal-free, visible-light photoredox-catalyzed three-component [3 + 2 + 1] heteroannulation for accessing modular fluoroalkylated pyrimidines from readily available silyl enol ether, amidine, and fluoroalkyl halide is developed. This protocol distinguishes itself by broad functional group tolerance in a regioselective manner, which provides a complement to the existing methods for the construction of pharmaceutically and biologically active organofluorine compounds. [ABSTRACT FROM AUTHOR]

A solvent-controlled catalyst-free chemoselective reaction was developed. Both 3,4-dihydroquinazoline-2-thiones and 2-imino[1,3]benzothiazines could be efficiently constructed by the reaction of 2-amino chalcones with isothiocyanates via two different chemoselective reactions depending on the solvents. The reaction was modulated by the solvents to proceed via either aza-Michael addition or thia-Michael addition as the major reaction with excellent yields. [ABSTRACT FROM AUTHOR]

A series of monodispersed fluoroperovskite nanocrystals with the size 20 nm were synthesized and rare earth doped. A series of KMF 3:Yb 3+,Er 3+(M = Mn, Zn, Cd, or Mg) up-conversion phosphor nanocrystals were synthesized. The emissions can be directly observed using the naked eye. Different red-to-green luminescent ratios for different host materials were discussed. Powder X-ray diffraction, transmission electron microscopy, and luminescence spectroscopy were used to characterize the products. The up-conversion mechanism was discussed. [ABSTRACT FROM AUTHOR]

In this paper, single-crystal metallic nanoplatelets, such as cobalt, nickel, copper, and silver, have been successfully synthesized based on a facile hydrothermal/solvothermal synthetic method. The as-prepared cobalt nanoplatelets had the 001 crystal facets as the basal plane, while the exposed nanoplatelet planes were assigned to be 111 crystal facets of the face-centered cubic nickel, copper, and silver crystals. Owing to the interesting combination of novel nanostructures, remarkable magnetic anisotropy was found on the cobalt and nickel nanoplatelets. The anisotropic copper and silver nanoplatelets exhibited a distinct surface plasmon resonance effect. These metallic nanoplatelets could be expected to bring new opportunities in the vast research areas of and application in magnetic storage devices, catalysts, and surface-enhanced Raman scattering. [ABSTRACT FROM AUTHOR]

Systematically shape-controlled synthesis of inorganic nanocrystals has attracted increasing attention recently for both fundamental and technological interest. The shape evolution of CdSe nanocrystals with wurtzite structure in a unified method has been previously well studied, while the study on shape evolution of CdSe nanocrystals with zinc blende structure still remains challenging. Here, we demonstrate a systematic shape variation of zinc blende CdSe nanocrystals in a modified organometallic approach, in which distinct shapes of cube-shaped, sphere-shaped, tetrahedron-shaped, and branched CdSe nano-crystals with high yield and good uniformity are obtained. The crucial factor that influences the shape-controlled process is the reactive temperature. This wide variation of shapes provides important information about the growth of CdSe nanocrystals, and it can also help in the shape-controlled synthesis of other nanocrystals that are bound with uniform crystal planes. [ABSTRACT FROM AUTHOR]