Nano-dimensional CeO2 nanorods for high Ni loading catalysts: H2 production by autothermal steam reforming of methanol reaction

Abstract

CeO2 nanorods were synthesized by a hydrothermal method and used as the support for preparing a series of Ni/CeO2 nanorod catalysts. The surface area of the catalysts decreased when the Ni percent over the CeO2 nanorods was increased. SEM results showed that the CeO2 is formed by nanorods approximately 1 μm in length. TEM and HREM revealed that the width of the nanorods is about 8 nm and it grew along the [1 1 1¯] axis. The catalytic activity of the catalysts was improved as the Ni was loaded onto CeO2 nanorods. The exposed planes of the CeO2 nanorod structure along the zone axis [0 1 1] for Ni impregnation were (1¯ 1¯ 1), (1 1 1¯), (1 1¯ 1), (1¯ 1 1¯), (2 0 0) and (2¯ 0 0) and they were more reactive for methanol conversion than (2¯ 2¯ 0), (2¯ 0 2¯), (0 2 2¯), (0 2¯ 2), (2 0 2) and (2 2 0) planes from the [1 1 1¯] axis (growth direction of the nanorod). This finding is mainly ascribed to the synergistic effect of the CeO2 nanorods and the Ni.