EXAFS study of the influence on structures of Ni in Ni/CeO2-ZrO2-Al2O3 catalyst for CO2 reforming of CH4 reaction by adding vapor

Ni/CeO2-ZrO2-Al2O3 catalysts were prepared using hydro-thermal method. CO2 reforming of CH4 reactions were carried out with or without vapor. The amount of carbon deposit and the EXAFS of K-edge of Ni were measured. The result shows that the nearest Ni-Ni coordination distances do not change obviously, but the coordination numbers of the nearest Ni-Ni shell change obviously. The nearest Ni-Ni coordination number reduces largely after reaction without vapor. For the condition of accession of vapor, the nearest Ni-Ni coordination numbers reduce much smaller than that of without vapor. The accession of vapor can reduce the amount of carbon deposit, stabilize the Ni structure, and thereby increase the stability of CO2 reforming of CH4 reaction