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In this study, we investigated the metal–support interactions over Ni/CeO 2 –ZrO 2 (Ni/CZ) catalysts for ethanol steam reforming. Different Ni contents (5, 10, and 15 wt%) were loaded onto the CZ support using two catalyst preparation methods, namely one-pot, and successive impregnation methods. Using the one-pot method, the Ni species over the Ni/CZ catalysts strongly interacted with the CZ support, resulting in smaller Ni nanoparticles with abundant oxygen vacancies. In contrast, the successive impregnation method mainly generated an isolated Ni phase at a high Ni content, resulting in large Ni clusters with limited oxygen vacancies. The poor Ni dispersion over the Ni/CZ catalysts prepared by the successive impregnation method induced low ethanol conversions and hydrogen production rates. In addition, the large Ni clusters over the Ni/CZ catalysts prepared by the successive impregnation method achieved a fast-coking behavior, thereby increasing the coke amount. Further, coke gasification was demonstrated to dominate the Ni surface with the Ni/CZ catalysts prepared by the one-pot method because of the high Ni dispersion and abundant oxygen vacancies. [Display omitted] • Ni/CeO 2 -ZrO 2 catalysts for ethanol steam reforming are prepared at different methods. • The one-pot method induces the strong Ni-CZ interaction over Ni/CZ catalysts. • Ni/CZ prepared by the one-pot method contains abundant oxygen species and Ni sites. • Ni/CZ prepared by the one-pot method enhances the H 2 production rate at 550 ℃. • Mild coking on the one-pot Ni/CZ catalysts is due to efficient coke gasification. [ABSTRACT FROM AUTHOR]

Abstract: CeO2 hollow microspheres have been fabricated through a simple thermal decomposition of precursor approach. The precursor with an average size of 10 μm was prepared in a reverse microemulsions containing Ce(NO3)3·6H2O and CO(NH2)2 at 160 °C. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED) and scanning electron microscopy (SEM). The possible formation mechanism of hollow spheres was discussed. In addition, the CeO2 hollow microspheres modified glassy carbon electrode exhibit excellent sensing performance towards methyl orange, which provide a new application of CeO2 hollow spheres. The catalytic activity of CeO2 hollow spheres on the thermal decomposition of ammonium perchlorate (AP) also was investigated by TGA. The catalytic performance of CeO2 hollow spheres is superior to that of commercial CeO2 powder. [ABSTRACT FROM AUTHOR]