A novel method has been used to synthesize rare earth oxide nanoparticles. Sm and Nd hydride nanoparticles were first produced by a hydrogen plasma−metal reaction. The evaporation rate of Sm is about three times that of Nd. Nd2O3 nanoparticles were then directly synthesized from the passivation of Nd hydride nanoparticles and Sm2O3 nanoparticles with a pure cubic structure from the heat treatment of Sm3H7 nanoparticles at 673 K in air. The morphology and crystal structure of the prepared powders were investigated by transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Both the Sm2O3 and the Nd2O3 nanoparticles were spherical in shape, with a mean particle diameter of about 40 and 17 nm, respectively. The particle size of the Sm2O3 nanoparticles changed very little after the sintering of the Sm hydride nanoparticles at 473 and 673 K.

For the first time, single crystalline Ni nanosheets have been successfully synthesized with the aid of iron species. The as-prepared nanosheets are mainly triangular and hexagonal in shape, with edge lengths ranging from several tens to several hundreds of nanometres. The exposed sheet planes are assigned to be (111) planes of a face-centred cubic nickel crystal. The well defined geometry enhances the anisotropic energy of Ni nanosheets, and therefore increases its blocking temperature (TB) to room temperature. Notably, the coercive force of the Ni nanosheets is 172 Oe at 300 K, which is significantly higher than that of the bulk one (ca. 0.7 Oe at room temperature). A possible mechanism is proposed to explain the formation of the thermodynamically unfavorable morphology of nanosheets. We suggest that crystal twinning, which is formed by etching of the introduced iron species with oleic acid, lowers the system energy, and leads to the growth of these Ni nanosheets.

One-dimensional nanostructure growth behaves very differently on the ± (0001) polar surfaces of wurtzite ZnO, resulting in asymmetric growth in these two directions. In this report we show that by tuning the degree of supersaturation, the growth asymmetry can either be rationally utilized or broken to obtain single- or double-sided ZnO nanocombs, respectively. The nanowires grown on the two polar surfaces of the double-sided nanocombs are of comparable length, suggesting some kind of symmetric growth, but they are distributed on the two sides in an asymmetric manner. More interestingly, the two sides of the double-sided nanocomb exhibit distinct optical properties. Possible mechanisms are proposed to explain the growth and optical properties of the double-sided nanocombs.

By using an arylthiolate ligand with a substituent in the paraposition, 4-tBuC 6

No abstract