Papers by Keyword: Nanoplate

Abstract: MoO₂ has been widely used in many fields such as catalyst, gas-senor, super capacitor and Li-ion battery electrode. In this paper, MoO₂ nanoplates were synthesized in high density and large scale on silicon substrates via simple thermal evaporation of MoO₃ and S powders at 950 °C in a tube furnace. The morphology, composition and structure of the nanoplates were characterized by scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The results indicate that the as-synthesized nanoplates are of well crystalline structure, and the thickness of these nanoplates is in the range of 100-300 nm. The growth mechanism of the nanoparticles was proposed as a vapor-solid process.

Abstract: Tungsten oxide is a kind of multifunctional materials with excellent properties for gas sensing, electrochromic and photocatalytic applications. In this study, Tungsten oxide nanoplate thin film was prepared by hydrothermal methods. The as-prepared thin film is composed of tungsten trioxide hydrate nanoplates, which are randomly orientate on the surface. The as-grown nanoplate thin film shows good sensitivity to H₂ gas. Dehydration and phase transition to γ-phase tungsten trioxide were found after annealing, and the sensitivity as well as the response time to H₂ were improved. We found that the nanoplate in the annealing sample bursts, which raises the surface-to-volume ratio for better hydrogen diffusion and reaction. The sensing mechanism was discussed. The findings provide a way to control the structure and surface morphology for improving the H₂ sensing properties of tungsten oxide.

Abstract: By a environmentally friendly method with the control of anionic amino acid surfactant N-lauroylsarcosine sodium (Sar-Na), hydroxyapatite (HAP) nanoplates were synthesized and the adsorption behavior of bovine serum albumin (BSA) were carefully studied. The products were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Results showed that hydroxyapatite nanocrystals with lengths of 100 nm, a width of 10 nm and a high aspect ratio (10:1) were obtained. Results of UV-Vis spectrum indicate that prepared hydroxyapatite nanoplates can be effectively adsorbed BSA. The current work provides a new approach to produce biomaterials.

Abstract: Gold nanostructures were synthesized at room temperature under irradiation of a fluorescent lamp in mixture of gold seeds smaller than 10 nm, HAuCl4, and poly(vinylpyrrolidone) (PVP). N,N'-dimethylformamide (DMF), water or ethylene glycol (EG) was used as solvent respectively. The products were characterized by transmission electron microscopy, X-ray diffraction and absorption spectra, and the results indicated that under light irradiation at ambient, the reducibility of the three solvents for HAuCl4 ranked as: EG> water> DMF, all far weaker than that of PVP; PVP also prevented the nanostructures from precipitating; gold seeds seemed to impose an autocatalytic effect to facilitate the reduction of HAuCl4; light irradiation was essential for high-yield production of gold particles; the above factors influenced the morphology and size of the gold structures, and led to formation of particles within nano or micron scale in shape of spheroid, rod or plate.

Abstract: The two dimensional nanoplates of WSe2 and MoSe2 are the result of solid-state thermal (750oC) reaction between micrometer-sized W or Mo with micro-size Se powder under inert atmosphere via carving phenomena in a closed reactor. This is a distinct top-down approach presented for the fabrication of inorganic nanoplates, where micron-sized metal particles having very high melting and boiling points are converted into a Se–M–Se sandwich structure employing a single-step, scalable, and environmentally- friendly chemical reaction under autogenic pressure at elevated temperature (RAPET). The mechanistic elucidation of the creation of WSe2/MoSe2 nanoplates is suggested on the basis of the crystal structure with the support of data obtained from compositional, structural, and morphological characterizations.