LAUSR

Abstract A series of LaNi1-xCoxO3 (x = 0, 0.2, 0.5, 0.8 and 1) perovskite catalysts were prepared successfully and applied for toluene steam reforming as a model tar molecule. The Ni–Co alloy formation in reduced LaNi1-xCoxO3 was confirmed by TPR, XRD and XPS. The strong interaction in LaNi0.8Co0.2O3 between Ni and Co produced highly dispersed and smaller metal (8–9 nm), higher reducibility and larger amounts of active sites as well as more abundant oxygen defects and higher surface/lattice oxygen mobility, confirmed by XRD, TEM, TPR, XPS and O2-TPD. Also, a higher electron density prevented Ni from oxidation and sintering; a more oxidized Co (Co3+) facilitated the dissociation of water and activation of CO2, thus removing the coke. At 600 °C, S/C = 3.4 and WHSV = 16.56 ml h−1 gcat−1, an equilibrium conversion was achieved initially and over 80% conversion after 24 h were obtained for LaNi0.8Co0.2O3 with a high H2 yield (81.8% at maximum) and 8.0 of H2/CO ratio. The graphitic/filamentous coke formation was alleviated and no metal sintering was presented after the reaction.