Composites of nanosized CdS–ZnS core–shell particles well dispersed in polycetyl- p-vinylbenzyldimethylammonium chloride (PCVDAC) were fabricated and their optical properties and morphology were studied. The core-shell particles of less than 10 nm in size were prepared with the reverse micellar solutions formed by a polymerizable anionic surfactant, CVDAC, and a direct thermal radical polymerization of the micellar solution led to the nanocomposite containing well-dispersed core–shell particles. The shell was inferred from small angle x-ray scattering to be around a monolayer thick. This monolayer coating, however, was enough to produce an appreciable enhancement in photoluminescence for the ZnS-coated CdS system (wider band gap material on narrower band gap material), and a degradation in photoluminescence for the CdS-coated ZnS system. However, a complete coverage of the CdS core with ZnS was required to realize the photoluminescence enhancement for the ZnS-coated CdS system. The polymer domains in the composite were found to be composed of lamellar stacks due to the comb-like structure of PCVDAC. The interlamellar distance was 3.9 nm with smectic liquid crystalline texture observed under polarized optical microscope. The core–shell particles were believed to locate at the grain boundary of the liquid crystalline domains.

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Ultrafast formation of ZnO mesocrystals was achieved with a facile, green, Tris-assisted, room temperature ionic liquid based antisolvent process. A deep eutectic solvent, formed by simply mixing and heating urea and choline chloride at 70 C, served as the solvent for ZnO, whereas Tris-containing de-ionized water acted as the anti-solvent to trigger the ultrafast formation of ZnO mesocrystals at 70 C. The product mesocrystals were mesoporous and near-single-crystalline with high specific surface areas, showing excellent photocatalytic activities toward photodegradation of methylene blue, comparable to that of a commercial photocatalyst, P-25 TiO 2 , which is rarely achieved for pristine ZnO. The present approach is a general one and can be readily extended to production of mesocrystals of other functional metal oxides.

An environmentally benign hydrothermal route was used to synthesize ultra-long double-ended needle-like ZnO microrods. The microrods were morphologically uniform with a diameter of around 1–2 µm, and a length of 40–50 µm. The rods were grown directly from an aqueous alkaline solution containing Zn(OH)42− ions, produced from ZnSO4 and NaOH, without using any structure-directing reagent. The products were characterized using x-ray diffraction, energy-dispersive x-ray analysis, scanning electron microscopy, ultraviolet–visible spectrophotometry, and photoluminescence, and the results are reported. The influence of the preparation parameters on the morphology of the ZnO products is also discussed.