Yu Jiang Wang

Low-Temperature Molten Salt Synthesis of NiWO4 Nanoparticles

NiWO4 nanoparticles were successfully synthesized by a molten salt method at 270°C. The as-prepared powders were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and exhibited a pure phase NiWO4 with about 50 nm in particle size and uniform nearly-spherical particle shape.

Synthesis of CdWO4 Nanoflakes and Nanorods by a Sonochemical Process

CdWO4 nanoflakes and nanorods have been successfully prepared through a mild template-free sonochemical method without any surfactants. The as-prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that the ultrasound irradiation played an important role in the formation of CdWO4 crystals. The results showed that CdWO4 nanoflakes were first formed at the early stage, and CdWO4 nanoflakes were transformed into nanorods as the ultrasonic time was prolonged from 0.5h to 1.5h.

Sodium Nitrate Assisted Hydrothermal Synthesis of Na0.5Bi0.5TiO3 Nanoflakes

Single-crystal Na0.5Bi0.5TiO3 nanoflakes have been successfully synthesized at 160°C with 8M NaOH by a hydrothermal method assisted by sodium nitrate. The as-prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The presence of sodium nitrate was found to play an important role in the growth of single-crystal Na0.5Bi0.5TiO3 nanoflakes.

Hydrothermal Synthesis and Ferromagnetic Properties of Mn-Doped Na0.5Bi0.5TiO3 Crystals

Pure phase Mn-doped Na0.5Bi0.5TiO3 crystals were successfully synthesized by a hydrothermal method. Magnetic loops measured at room temperature indicate that ferromagnetism can be obtained in Mn-doped Na0.5Bi0.5TiO3 crystals, and the magnetism of Na0.5Bi0.5TiO3 crystals can be controlled by adjusting Mn doping concentration. The magnetism of the Mn-doped Na0.5Bi0.5TiO3 crystals varied from diamagnetism, ferromagnetism, and paramagnetic on increasing Mn doping concentration from 0 to 30mol%. The results showed in this study may provide an approach to widely exploring more multiferroic materials.

Hydrothermal Synthesis and Characterization of PbTiO3 Microrods

PbTiO3 microrods were successfully synthesized via a surfactants-free hydrothermal method. The powders were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and photoluminescent spectra techniques (PL). It was found that the precursor played a key role in the formation of PbTiO3 microrods.

Synthesis of PZT Disks by a Hydrothermal Method

The organization of nanostructures across extended length scales is a key challenge in the design of integrated materials with advanced functions. PbZr0.52Ti0.48O3 multilayer disks which were constructed by oriented rectangle nanoparticles were easily prepared by a simple surfactant-free hydrothermal process. The as-prepared powders were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results indicated that the as-prepared PZT disks were constructed by self-assembly of rectangle nanoparticles by a perfect manner. The formation mechanism of the products was discussed.

Hollow Crystals of BiFeO3 Prepared via a Al3+-Assisted Hydrothermal Method

The BiFeO3 hollow crystals were successfully prepared at 200oC by a Al3+ assisted hydrothermal method. The structures and morphologies of the as-obtained products were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (SEM). A morphology evolution from irregular shape to square, hollow, and sphere-like was observed as the Al ions concentration varied from 0% to 1.5%. The possible growth mechanism of the BiFeO3 hollow crystals was also discussed.

Mineralizer Mediated Self-Assembly of PbTiO3 Crystals

PbTiO3 crystals with different morphologies, such as flower-like and spherical shape, which was constructed by oriented nanoparticles have been obtained by a simple surfactant-free hydrothermal process assisted by K2CO3 as a mineralizer. Powder X-ray diffraction (XRD) analysis was applied to examine the purity and crystallinity of the as-prepared samples. The morphologies have been characterized by scanning electron microscopy (SEM). The results indicated that the self-assembly structures of PbTiO3 crystals were dependent on the addition amount of K2CO3 and the formation mechanism of the products was briefly discussed.

Effect of Precursor on the Hydrothermal Synthesis of K0.5Bi0.5TiO3 Crystals

K0.5Bi0.5TiO3 nanoparticles and quadrate nanoflakes were successfully prepared by a hydrothermal process. The as-synthesized powders were examined by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results suggest that the precursor plays an important role on the formation of K0.5Bi0.5TiO3 crystals and the formation mechanism was also discussed.

Hydrothermal Synthesis and Characterization of BiFeO3 Polyhedral Crystallites

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.