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ABSTRACT A malayaite pigment was synthesized with wastewater containing low chromium (Cr)(VI) by a novel liquid-phase reaction method. The effects of the particle size of the precursor and calcination temperature [...]

Ternary alloys of CdS xSe1− x nanorods have been synthesized by the thermal treatment of Cd2+ dispersed polyethylene glycol 2000 gel (PEG2000) with ethylenediamine solution of sulfur and selenium in a sealed system at 180 °C for 24 h, during which the proportion between S and Se in the nanorods was controlled by the ratios of every starting material to each other. The alloyed ternary CdS xSe1− x nanorods are highly crystalline without any other phase. The optical property these nanorods could be manipulated by modulating the composition of S and Se. [ABSTRACT FROM AUTHOR]

Abstract: The spherical particles CdSe x S1− x with 30–80 nm in radius have been successfully prepared by the hydrothermal reaction at 200 °C. The structure characterization which has been carried out using X-ray diffraction (XRD) shows hexagonal crystal structure. Novel properties have been observed via UV–visual absorption spectra and photoluminescence (PL) spectra. The absorption shoulder and the luminescence emission peaks have been tuned by changing the mole ratio of Se in the CdSe x S1− x samples. [Copyright &y& Elsevier]

We present first principles studies based on density functional theory (DFT) to investigate the lithium intercalation process in spinel manganese oxide compound. The lattice volume change, energetics, and insertion voltage were systematically examined upon sequential lithium insertions into the lattice. The charge transfer mechanism upon lithium intercalation was studied by analyzing the calculated spectra of density of states. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [ABSTRACT FROM AUTHOR]

Abstract: Single-crystalline α-MnO2 nanorods have been successfully synthesized by a novel hydrothermal method based on the redox reactions between the permanganate anion MnO4 – and H2O in mixture containing KMnO4 and HNO3. The products have been characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR) and Brunauer–Emmett–Teller (BET). The results prove that the grain size of α-MnO2 nanorods with the surface area ∼95.2m2 g−1 is homogeneous with diameters ranging from 10 to 20nm. The electrochemical property of the material shows that compared with the commercial electrolytic manganese dioxide (EMD), the discharge capacity of the as-prepared α-MnO2 nanorods is increased by 70.4%, 104.1% and 135.7% at different constant currents of 50, 250 and 500mAg−1, respectively. [Copyright &y& Elsevier]

Abstract: Various α-MnO2 nanostructures have been successfully synthesized by a simple hydrothermal method based on the redox reactions between the MnO4 − and H2O in mixture containing KMnO4 and HNO3. The effect of varying the hydrothermal time to synthesize MnO2 nanostructures and the forming mechanism of α-MnO2 nanorods were investigated by using XRD, SEM and TEM. The results revealed an evolvement of morphologies ranging from brushy spherical morphology to nanorods depending upon the hydrothermal time. The surface area of the synthesized nanomaterials varied from 89 to 119m2/g. Electrochemical properties of the products were evaluated using cyclic voltammetry and galvanostatic charge–discharge studies, and the sample obtained by hydrothermal reaction for 6h at 120°C showed maximum capacitance with a value of 152F/g. In addition, long cycle life and excellent stability of the material were also demonstrated. [Copyright &y& Elsevier]

A malayaite pigment was synthesized with wastewater containing low chromium (Cr)(VI) by a novel liquid-phase reaction method. The effects of the particle size of the precursor and calcination temperature on the final product are examined. The result of scanning electron microscopy shows that the obtained precursor is amorphous and the particle size is approximately 250 nm. The results of X-ray diffraction and differential scanning calorimetry show that the complete transformation temperature was approximately 1050 degrees C. Furthermore, the Commission International de l'Eclairage laboratory shows that the red color of as-prepared pigments is more saturated with a high a* value at 34.1. This process of malayaite pigment preparation via reuse of the Cr(VI)-containing wastewater is quite simple, economical, and energy-saving for the industry, and the products have a saturated red color. There is considerable foreground for the industrial application of this work.

Alumina is the most frequently employed catalyst or catalytic support in the chemical industry. The catalytic performances of alumina-supported catalysts are largely dependent on the textural properties of the alumina supports. Therefore, any improvement of the alumina properties significant for their catalytic applications is extremely challenging. Ordered mesoporous aluminas with high thermal stability have been successfully prepared by a facile synthesis method. Using the ordered mesoporous aluminas as support, V/Ni-catalysts mesoporous materials also have been prepared by vacuum impregnation method and the coprecipitation method. The mesoporous structures are characterized by XRD, TEM, N2 adsorption -desorption and TG-DTA. Preliminary catalytic tests showed that the ordered mesoporous aluminas prepared in such a way exhibited superior performance in the oxidative dehydrogenation of propane to propylene when they were used as the supports for V and Ni catalysts.

A novel tri(8-hydroxyquioline) aluminum (AlQ3) nanostructure was prepared on large scale at low cost by low-temperature physical vapor deposition (PVD). The morphologies, the chemical bondings, and photoluminescence of the AlQ3 nanostructure were investigated by environmental scanning electronic microscopy (ESEM), Fourier transform infrared spectrum (FT-IR), and photoluminescence (PL) spectra, respectively. The AlQ3 nanostructure was composed of micro-sphere with nanowire-cluster growing on the surface. The diameter of micro-sphere and nanowire were about 5 microm and 80 nm, respectively. FT-IR results indicated that the AlQ3 molecule had a strong thermal stability under research conditions. The growth mechanism of the novel nanostructure was discussed. The novel organic nanostructure would be believed to attractive building field-emission devices and other optical devices.