Ultrathin ZnSe nanorods in the cubic phase have been synthesized by the reaction of selenium and zinc oleate for 30 min at 240 °C. These nanorods showed an average diameter of 2.4 nm, which is much smaller than the Bohr size of bulk ZnSe. Thus, they exhibited a remarkable quantum size effect in terms of their optical properties. The formation of the ultrathin nanorods could be attributed to the oriented attachment mechanism, which was supported by the structure of the nanorods and the control experiments. The ultrathin nanorods were transferred into an aqueous solution by ligand exchange. The performance of these nanorods as a catalyst was examined, using the photodegradation of methyl orange as a model reaction. It was found that the ultrathin nanorods possessed better photocatalytic activities than conventional ones.

Heterodimer nanostructures have attracted extensive attention, owing to an increasing degree of complexity, functionality, and then importance. So far, all the reported ones are built from solid nanoparticles. Herein, nearly monodisperse heterodimer nanostructures are constructed by hollow PbS_x and solid Au domains simultaneously through a mild reaction between PbS nanocrystals and the gold species in the presence of dodecylamine. Control experiments clearly reveal the underlying formation mechanism of the hollow PbS_x–solid Au heterodimers. The Au^III species in the solution, lead to the etching of PbS nanocrystals and the Au^I species facilitate the control of the number of gold domains per nanoparticle. Dodecylamine molecules not only work as a stabilizer in the reaction, but also act as a reducing agent that could greatly affect the morphology of the product. The optical properties of the heterodimers are investigated based on UV/Vis absorption spectroscopy and Raman spectroscopy. This novel heterodimer nanostructure pushes the development of complex nanocrystal-based architectures forward, and also provides many opportunities for potential applications.