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The chemical reduction of selenious acid solution with hydrazine hydrate in the presence of poly(vinylpyrrolidone) (PVP) has produced a stable dispersion of monodisperse amorphous selenium nanoparticles capped with PVP and a size of 100nm. The results have shown that the enrichment of nanoparticles with amphiphilic property onto a liquid-liquid interface between a polar solvent and another solvent of low polarity can result in crystallization and phase transformation for the formation of nanostructures.

Semiconductor CdS and CdSe nanostructures with complex form such as urchin-like nanoflowers, branched nanowires and fractal nanotrees were synthesized via a facile solvothermal approach in a mixed solution made of diethylnetriamine (DETA) and deionized water (DIW). The results showed that the morphologies of CdS and CdSe nanocrystals can be controlled via tuning the volume ratio of DETA and DIW suggesting that the photocatalytic property of CdS nanostructures is related to its unique structural feature.

A simple polypeptide-directed strategy for fabricating large spherical assembly of CaCO3 nanoparticles is reported. Stepwise growth and assembly of a large number of nanoparticles are observed, from the formation of an amorphous liquidlike CaCO3-polypeptide precursor, to the crystallization and stabilization of polypeptide-capped nanoparticles, and, eventually the spherical assembly of nanoparticles.

Unusual ZnO superstructures with ring-like nanosheets standing the backbone of spindles were synthesized from Zn5(OH)(sub 8)Cl2[.]H2O nanosheets by a mild solution route. The fast supersaturation for the formation of the ZnO phase can be achieved by using the precursor, which already has rich hydroxyl groups.

The Langmuir-Blodgett technique without any extra hydrophobic pretreatment or functionalization is utilized to produce well-defined periodic mesostructures of hydrophilic ultrathin Te nanowires with aspect ratios of at least [10.sup.4]. The method could also be extended for fabrication of other mesostructured assemblies of ultrathin nanowires or nanotubes.

Unique ultrathin Co[Se.sub.2]-DETA (protonated) mesostructured nanobelts with multiple stacked layers that are parallel to the axial direction are prepared in a binary solution composed of organic amine and water under mild solvothermal conditions. This strategy might provide new ways for preparing other new mesostructured nanomaterials, which might bring new nontrivial functionalities.

A simple solvothermal method is described for preparing single-walled flux-closure Ni-Co magnetic alloy nanorings in high yield. High nickel content on the alloy and high poly(vinylpyrrolidone) (PVP) concentration has favored the fabrication of nanorings.

The different phases and morphologies of molybdate hydrates MMo[O.sub.4].n[H.sub.2]O (M = Co, Ni, Mn, n = 0, 3/4, 1) nano/microcrystals, which has included NiMo[O.sub.4].[H.sub.2]O microflowers, MnMo[O.sub.4].[H.sub.2]O microparallogram plates, and CoMo[O.sub.4].3/4[H.sub.2]O microrods, is prepared by a hydrothermal process. The electrochemical performances of MMo[O.sub.4] (M = Ni, Co) nanorod bundles and MnMo[O.sub.4] microrods are evaluated.

The synthesis of unique necklace-like poly-(vinyl alcohol) (PVA) microcables that have strict wire-bead forms is reported. The process of PVA cross-linking and formation of dispersing cross-linked PVA microspheres are strengthened under hydrothermal condition at lower pH values.

A novel polymer-controlled mineralization reaction is proposed for the synthesis of ringlike CaC[O.sub.3] superstructures. The proposed formation mechanism of such rings is based on the formation of CaC[O.sub.3] nanoparticles in disordered block copolymer assemblies which leads to the formation of a polymer concentration gradient and as the polymer contains multiple chelating units, this leads to dissolution of the particle core forming the mesorings.

Superlong single crystal tellurium nanoribbons with a width of 200-300 nm and length up to several hundred micrometers are synthesized in tetraethylene pentamine aqueous solution at 80 degree centigrade. The erosion phenomenon is not identified and it is suggested that tellurium nanoribbons synthesized by other chemical methods can be not stable in solution system and their storage after laboratory synthesis requires special attention.

Uniform and monodisperse CuO nanorods are synthesized by directional aggregation and crystallization of tiny CuO nanoparticles generated from a solid-liquid arc discharge process under ambient conditions in the absence of any surfactants. Uniform CuO nanorods with sharp ends are formed from tiny nanoparticles through a process that involves the rapid oxidation of Cu nanoclusters, the spontaneous aggregation of CuO nanoparticles, and Ostawald ripening process.

A simple large-scale hydrothermal synthesis of flexible nanocables with silver as cores and cross-linked poly(vinyl alcohol) (PVA) as shells is demonstrated. The in situ reduction of silver ions in the presence of PVA is possibly due to the catalysis of silver ions on the cross-linking of PVA chains under hydrothermal conditions.

An attempt made to identify that well-crystallized ZnWO4 nanorods can direct the self-aggregation of the amorphous nanoparticulates and promote the crystallization is reported. Further, the transformation of the amorphous nanoparticles derived from a simple supersaturation precipitation reaction in a nanorods/amorphous nanoparticle coexisting system under either refluxing conditions or mild hydrothermal conditions are presented.

A simple hydrothermal route is discovered to synthesize single-crystal CuGe[O.sub.3] (CGO) nanobelts with a layered mesostructure. The produced CGO nanobelts show distinct susceptibility behaviors in comparison with CGO bulk crystals.