Influence of electronic effect on methane catalytic combustion over PdNi/Al2O3

A series of PdNi/Al2O3 catalysts with different compositions was prepared by co-reduction method. The influence of Ni amount on the catalytic combustion of methane was studied. X-ray diffractometry and X-ray photo-electron spectroscopy were employed to characterize the dispersion and electronic state of the active phase. Temperature-programmed oxidation was carried out to study the thermal stability affected by Ni doping. It has been demonstrated that Ni addition changed particle size and oxidation state of PdO (x) . The results indicate that the promotion of Ni to the Pd/Al2O3 resulted from both size effect and electronic effect. In addition, the thermal stability of the Ni-doped catalysts were enhanced.