Ying Chu

Controllable Synthesis of Nickel Hydroxide and Porous Nickel Oxide Nanostructures with Different Morphologies

Alpha-Ni(OH)(2) nanobelts, nanowires, short nanowires, and beta-Ni(OH)(2) nanoplates have been successfully prepared in high yields and purities by a convenient hydrothermal method under mild conditions from very simple systems composed only of NaOH, NiSO(4), and water. It has been found that the ratio of NaOH to NiSO(4) not only affects the morphology of the Ni(OH)(2) nanostructures, but also determines whether the product is of the alpha- or beta-crystal phase. A notable finding is that porous NiO nanobelts were produced after exposure of the Ni(OH)(2) products to an electron beam for several minutes during transmission electron microscopy (TEM) observations. Another unusual feature is that rectangular nanoplates with many gaps were obtained. Furthermore, porous NiO nanobelts, nanowires, and nanoplates could also be obtained by annealing the as-prepared Ni(OH)(2) products. A sequence of dissolution, recrystallization, and oriented attachment-assisted self-assembly of nanowires into nanobelts is proposed as a plausible mechanistic interpretation for the formation of the observed structures. The method presented here possesses several advantages, including high yields, high purities, low cost, and environmental benignity. It might feasibly be scaled-up for industrial mass production.

Synthesis and characterization of ring-like α-Fe2O3

A novel ring-like α-Fe2O3 with a cave at the centre was first synthesized via the redox reaction of Fe2+ with S2O82− in solution. The samples were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The possible mechanisms of shape evolution for the formation of ring-like α-Fe2O3 were discussed. Magnetic hysteresis measurements revealed that the ring-like α-Fe2O3 display a magnetic behaviour with a coercivity of 1690 Oe at room temperature. The photocatalytic degradation of salicylic acid revealed that ring-like α-Fe2O3 exhibits a photocatalytic property.

Room-temperature controllable fabrication of silver nanoplates reduced by aniline

Ag nanoplates are the first generated by the reductant aniline in the presence of poly(vinyl pyrrolidone) (PVP) at room temperature without stirring in the reaction process.

One-step synthesis and properties of urchin-like PS/α-Fe2O3 composite hollow microspheres

A new progressive hard template method has been developed to synthesize uniform polystyrene (PS)/α-Fe2O3 composite hollow microspheres under hydrothermal conditions. Sulfonated polystyrene (PS) microspheres were used as templates as well as the endothecia of the composite microspheres; Fe2O3 shell was obtained through the reaction of FeSO4 and KClO3 under hydrothermal conditions. Field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) studies showed that the as-obtained products consist of large scale monodisperse urchin-like hollow microspheres. In comparison with the Fe2O3 of other structures, the composite hollow microspheres have good photocatalytic activity, large surface area and a high remanent magnetization. A possible mechanism for the formation of composite hollow microspheres is also proposed in the paper.

Two-minute synthesis of PbS nanocubes with high yield and good dispersibility at room temperature

A novel water/glycerol/polyvinylpyrrolidone (PVP) ternary system is developed to realize the successful growth of PbS nanocubes with a narrow size distribution and sharp facets and edges using a one-step synthesis at room temperature for the first time. The synthesis is very fast, high yield, environment-friendly, and low cost. The product possesses uniform dimensionality, high crystallinity and better dispersibility. After dispersing the nanocubes in water or ethanol, the as-formed colloidal suspensions can maintain excellent stability for more than one year under ambient conditions. Uniform silica layers were successfully coated onto the nanocubes via a modified Stöber method to enhance their performance for promising applications. Moreover, by soaking the as-prepared PbS/SiO(2) core-shell nanocubes in hydrochloric acid aqueous solution, well-resolved cubic SiO(2) nanoboxes were obtained. The formation mechanism and the reason for the better dispersibility and excellent stability of the as-obtained nanocubes are also discussed rationally.