Abstract:
Different morphologies of CeO
2 supports (including CeO
2-R rod, CeO
2-C cube, and CeO
2-P polyhedron) were synthesized by hydrothermal method and were used to develop Ni
3Fe/CeO
2 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, N
2 adsorption-desorption, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and thermogravimetry analysis. The results showed that Ni
3Fe/CeO
2-R exhibited good catalytic activity in DRM, where CH
4 as well as CO
2 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 Ni
3Fe/CeO
2-R was relatively stable and graphitic degree of coke deposition was low after 10 h. Meanwhile, the oxidative resistance of Ni
3Fe/CeO
2-R was improved as confirmed by the existence of stable Ni
3Fe alloy after reaction, which mitigated the facile oxidation of more oxyphilic Fe species on the alloy by the promotion of CO
2 activation on the vacancies of CeO
2-R.