Nanoporous CuO/CeO2 ribbons are successfully prepared through dealloying melt-spun Al80−xCu20Cex (x = 0.5, 1, 2, 3, at%) alloy in a 5 wt% NaOH aqueous solution, followed by calcining in air. The samples are characterized by XRD, SEM, EDS, HRTEM, Raman and gas chromatograph. For the dealloyed melt-spun Al80−xCu20Cex (x = 0.5, 1, 2, 3, at%) alloy, the XRD results indicate that Cu and Cu2O are for...

Cerium oxide (CeO2) or ceria has been shown to be an interesting support material for noble metals in catalysts designed for emission control, mainly due to its oxygen storage capacity. Ceria nanoparticles were prepared by precipitation method. The precursor materials used in this research were cerium nitrate hexahydrate (as a basic material), potassium carbonate and potassium hydroxide (as pre...

The catalytic activity for CO oxidation over cerium dioxide (CeO2) and Cu-modified ceria (Cu/CeO2) powders prepared by wetness impregnation method was investigated in flow tube reactor system under atmospheric pressure. Reaction curves of powder samples pre-treated by calcination in mixture of argon and oxygen and by reduction in hydrogen, all at 300 °C were measured. X-ray photoelectron spectr...

The CO preferential oxidation (PrOx) is one of the critical steps in hydrogen production and purification for Polymer Electrolyte Membrane Fuel Cell (PEMFC). This reaction was investigated in the presence of excess hydrogen over Cu/CeO2, Pt/CeO2 and Cu-Pt/CeO2 catalysts. The ceria supports was prepared via precipitation method and Cu-Pt/CeO2 catalyst was synthesized by sequential impregnation o...

The aim of the PROX reaction is to reduce the CO content of hydrogen feed to proton exchange membrane fuel cells (PEMFC) by selective oxidation of CO in the presence of excess hydrogen. Both Pt and Pd on ceria are active in CO oxidation (without hydrogen) while Pd is poorly active in the presence of hydrogen. In this paper we aimed at finding the reasons of such behavior, using the same techniq...

The cytotoxicity of 13 and 22 nm aluminum oxide (Al2O3) nanoparticles was investigated in cultured human bronchoalveolar carcinoma-derived cells (A549) and compared with 20 nm CeO2 and 40 nm TiO2 nanoparticles as positive and negative control, respectively. Exposure to both Al2O3 nanoparticles for 24 h at 10 and 25mgmL 1 doses significantly decreased cell viability compared with control. Howeve...

Nanosized CuO-CeO2, CuO-Fe2O3, CuO-CeO2-Al2O3 and CuO-Fe2O3-CeO2-Al2O3 were prepared by co-precipitation and wet impregnation techniques and were used for Catalytic decomposition of acetylene to produce carbon nanotubes (CNTs). Weight gain technique was used to follow up the catalytic reactions. The results revealed that catalyst chemical composition, catalytic temperature, acetylene flow rate ...

We herein report the synthesis of 3-methyl-1,3-butanediol from isobutene and HCHO in water via a Prins condensation-hydrolysis reaction over CeO2, which is a water-tolerant Lewis acid catalyst. The CeO2 exhibits significant catalytic activity for the reaction, giving 95% HCHO conversion and 84% 3-methyl-1,3-butanediol selectivity at 150 ◦C for 4 h. The crystal planes of CeO2 have a significant ...

The properties of 20 wt % CeO2 and 21 wt % Ce0.5Zr0.5O2 films, deposited onto a γ-Al2O3 by Atomic Layer Deposition (ALD), were compared to bulk Ce0.5Zr0.5O2 and γ-Al2O3-supported samples on which 20 wt % CeO2 or 21 wt % CeO2–ZrO2 were deposited by impregnation. Following calcination to 1073 K, the ALD-prepared catalysts showed much lower XRD peak intensities, implying that these samples existed...

The x-ray diffraction study of 12 nm CeO2 was carried out up to ~40 GPa using an angle dispersive synchrotron-radiation in a diamond-anvil cell with different pressure transmitting medium (PTM) (4:1 methanol: ethanol mixture, silicone oil and none) at room temperature. While the cubic fluorite-type structure CeO2 was retained to the highest pressure, there is progressive broadening and intensit...