Dry reforming of methane over bimetallic Ni-Co catalyst prepared from La (CoxNi1-x)0.5Fe0.5O3 perovskite precursor: Catalytic activity and coking resistance

Exploring highly active Ni based catalysts with high coking resistance is of great importance for dry reforming of methane. Bimetallic Ni-Co catalysts supported on La2O3-LaFeO3 were prepared by reducing La(Coxl iii..)o.sFeo.503 perovskite precursors. The perovskite precursors adopt orthorhombic, rhombohedral crystalline structure, or both, depending on the Co content. The catalytic activity and coking resistance are obviously enhanced by substituting a proper amount of Co, which should be essentially attributed to the synergistic effect between Ni and Co. Interestingly, the crystalline structure of the perovskite also plays an important role. Catalysts reduced from orthorhombic perovskite precursors with x = 0.10 and 0.30 have obvious higher structural stability, which show maximal catalytic activity and coking resistance. The multiple valences and spin states features of Co cations may affect the stability of the perovskite structure, and thus affect the active oxygen species in the perovskite, which promote both the catalytic activity and the removal of deposited carbon species.