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Pt/CoAl2O4/Al2O3, Pt/CoOx/Al2O3, CoAl2O4/Al2O3 and CoOx/Al2O3 catalysts were studied for combination CO2 reforming and partial oxidation of CH4. The results indicate that Pt/CoAl2O4/Al2O3 is the most effective, and XRD results indicate that Pt species are well dispersed over the Pt/CoAl2O4/Al2O3. High dispersion is related to the presence of CoAl2O4, formed during calcining at high temperature before Pt addition. In the presence of Pt, CoAl2O4 in the catalyst could be reduced partially at 973 K. Based on these results, it appears that zerovalent platinum with high dispersion and zerovalent cobalt resulting from CoAl2O4 reduction are responsible for high activity in the Pt/CoAl2O4/Al2O3 catalyst. [ABSTRACT FROM AUTHOR]

Pt/CoAl2O4/Al2O3, Pt/CoOx/Al2O3, CoAl2O4/Al2O3 and CoOx/Al2O3 catalysts were studied for combination CO2 reforming and partial oxidation of CH4. The results indicate that Pt/CoAl2O4/Al2O3 is more effective, and XRD results indicate that Pt species are well dispersed over the Pt/CoAl2O4/Al2O3. High dispersion is related to the presence of CoAl2O4, formed during calcining at high temperature before Pt addition. In the presence of Pt, CoAl2O4 in the catalyst could be reduced partially at 973 K. Based on these results, it appears that zerovalent platinum with high dispersion and zerovalent cobalt resulting from CoAl2O4 reduction are responsible for high activity in the Pt/CoAl2O4/Al2O3 catalyst. [Copyright &y& Elsevier]

Abstract: Novel visible-light-driven AgX/g-C3N4 (X=Br, I) hybrid materials were synthesized by the facile water bath method. The AgX/g-C3N4 hybrid materials were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), Fourier transform infrared spectra (FTIR), Raman and the special surface area. The XRD, EDS, TEM, FTIR, Raman and XPS analyses indicated that AgX nanoparticles were evenly distributed on the surface of g-C3N4 and the heterostructures were formed. The photocatalytic activity of the AgX/g-C3N4 hybrid materials was evaluated using methyl orange as a target organic pollutant. The as-prepared AgX/g-C3N4 hybrid materials displayed much higher photocatalytic activity than the pure g-C3N4 and AgX nanoparticles. After the introduction of AgX nanoparticles, the photocurrent of the AgBr/g-C3N4 and AgI/g-C3N4 hybrid materials was found to increase by 21 and 8 times than that of the pure g-C3N4, respectively. The increased photocatalytic activity of the AgX/g-C3N4 hybrid materials was attributed to the synergic effect between g-C3N4 and AgX, which included the optical property, the better dispersion and the small size. A photocatalytic mechanism and the kinetics of AgX/g-C3N4 hybrid materials were also proposed. [Copyright &y& Elsevier]

Abstract: Highly dispersed MoV0.3Te0.23Nb0.1O/SiO2 catalysts prepared by the sol–gel method show high activity and selectivity for the oxidation of propane to acrolein. The best result was obtained on the catalyst ((Mo+V+Te+Nb)/Si=2mol%) with 45.9% selectivity of acrolein at the propane conversion of 39.9%. The catalysts were characterized by BET, XRD, Raman, TPR and XPS. The results showed that the higher performance of the catalysts prepared by the sol–gel method might be facilitated by the higher specific surface, a better dispersion of the active species on the support, as well as a lower reduction peak temperature. [Copyright &y& Elsevier]