Effect of support morphology of Ni₃Fe/CeO₂ on catalytic performance for dry reforming of methane

Different morphologies of CeO₂ supports (including CeO₂-R rod, CeO₂-C cube, and CeO₂-P polyhedron) were synthesized by hydrothermal method and were used to develop Ni₃Fe/CeO₂ catalysts by impregnation method for dry reforming of methane (DRM). The structures of the resultant catalysts before and after DRM were characterized by X-ray diffraction, N₂ adsorption-desorption, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and thermogravimetry analysis. The results showed that Ni₃Fe/CeO₂-R exhibited good catalytic activity in DRM, where CH₄ as well as CO₂ conversion reached to 82% and 91%, respectively, at 800 ℃, owing to its large specific surface area and high oxygen vacancy concentration. The catalytic performance of Ni₃Fe/CeO₂-R was relatively stable and graphitic degree of coke deposition was low after 10 h. Meanwhile, the oxidative resistance of Ni₃Fe/CeO₂-R was improved as confirmed by the existence of stable Ni₃Fe alloy after reaction, which mitigated the facile oxidation of more oxyphilic Fe species on the alloy by the promotion of CO₂ activation on the vacancies of CeO₂-R.