We have demonstrated the dimerization of single-crystalline Ag nanocubes with reasonably high yields through stepwise integration by following three steps: the preparation of a single layer of densely packed Ag nanocubes on a substrate by modified convective assembly, the selective functionalization of the upper face of the Ag nanocubes with a hydrophobic DT-SAM using the μCP approach, and the spontaneous dimerization in a mixture of ethanol and water driven by enhanced anisotropic hydrophobic interparticle interactions. Face-selective functionalization using hydrophobic DT-SAM gave the nanocubes directionality with respect to their anisotropic interparticle interactions under an external hydrophilic environment. We conclude that the driving force that reduced the surface area of the hydrophobic faces is sufficient large to form an ordered assembly of nanosized building blocks in an aqueous solution. Both experimental and theoretical studies revealed that the 50-nm-diameter Ag nanocubes dimers with a ca. 3.3 nm gap at their junction exhibited two plasmon peaks centered at 446 nm and 600 nm, which contributed to transverse and longitudinal plasmon resonances, respectively. Elctromagnetic calculations based on the FDTD method clearly showed that a greater enhancement of the local field occurred, with an average amplitude of the electric field of 1.0×1015, at the fractal space between the aggregated Ag nanocubes when the dimer was illuminated under longitudinally polarized light.

Cro/CrOx-doped hybrid glasses are designed to develop novel laser device materials by inserting alkylene spacers between inorganic oxides. In TEM images, morphology of the organically modified hybrid glasses reveals highly arranged nano-periodic patterns. The nano-patterns observed from the hybrid glass based on alkylene-bridged xerogel are sustained over substantial domains and appears to arise from modified glassy lattice fringes. In electron diffraction pattern, it also shows the circled diffraction patterns arise from Cro/CrOx. In laser experiments, the hybrid glass shows a new optical property, which generates a huge acoustic wave; the diffraction efficiency (45 %) of the modified glass is higher than that of methanol (25 %); it means that the compressibility of the solid type of glass is as effective as the liquid. The hybrid glass shows a new optical property that hitherto hasn’t been found and could be useful for developing diffraction beam modulators.

Exquisite control of surface functionality is essential to tailor the chemical and physical properties of metal nanocrystals to the requirements of specific applications. Hybridization of gold nanoparticles with other components such as polymers and metal oxides can effectively introduce appropriate functionalities on the surface without changing their own properties, and thereby become a basic architecture for various applications such as sensors and catalysts. In the present work, we report two hybrid nanostructures comprising gold nanocrystals. PDMAEMA (poly(dimethylaminoethylmethacrylate))–gold hybrid nanocrystals were synthesized via a polyol process, which produced carboxylate functionality on the gold surface. This hybrid structure was employed for a sensitive pH-sensor in solution. On the other hand, porous silica-gold hybrid nanoreactors were produced by selective etching of gold cores from gold@silica core-shell particles. The nanoreactor framework exhibited high and controllable activity on the reduction of aromatic nitroxides. These two examples of hybrid gold architectures would be able to apply for other metal and metal oxide systems to develop biosensors and energy production catalysts.

Copper oxalate 1 �m-sized nanocrystalline assemblies with several shapes (cushions, lenses, drilled cushions, and square rods) have been obtained by aqueous precipitation without additive, with glycerol, with PEG and with HPMC. Respective influences of these additives on the nanocrystals self-assembly are suggested from the obtained particles morphologies to provide a better understanding of this assembly process. Raman spectroscopy is used to highlight fluorescence occurring on the copper oxalate samples synthesized with additives. This additive induced fluorescence is suggested to result from specific interactions between the nanocrystals and the adsorbed additives.

Here we developed a new method to prepare the liquid crystal particles by first synthesizing the monodisperse hollow inorganic spheres and then allowing the liquid crystals to infiltrate into the hollow spheres. The resulting liquid crystal colloidal particles have a diameter of 285nm with a low polydispersity of 0.03. DSC thermograms showed a clear peak at around 30 degree, indicating the isotropic-nematic transition of liquid crystals encapsulated in the silica shells. The inorganic shells can prevent liquid crystals inside from leaking out and also hold the spherical shape of colloidal particles after the evaporation of the dispersant. A thin film assembled by the liquid crystal colloidal particles was also prepared in this report.

Cu-In-S nanocrystals were developed as a low toxic fluorescent. The stoichiometric CuInS2 nanocrystals were synthesized facilely by heating a solution of metal complexes. The fluorescence would be originated from the crystal defect. We intentionally introduced the crystal defects related to Cu deficiency in nanocrystal with the prospect that the fluorescence intensity would be increased. The nanocrystals have many defects without phase separation as observed in bulk material. Consequently, the fluorescence quantum yield achieved to c.a. 6%. Moreover, the fluorescence quantum yield was increased up to 15% by the ZnS-coating.