Nanoparticles of Cu–Co alloy supported on high surface area LaFeO3—preparation and catalytic performance for higher alcohol synthesis from syngas

Abstract

LaFeO₃ supported Cu–Co bimetallic catalysts with high surface area and mesoporosity were prepared by impregnation combined with nanocasting method, and the resulting catalysts were used for higher alcohol synthesis (HAS) from syngas. These catalysts were characterized by using N₂ adsorption and desorption, X-ray diffraction, temperature programmed reduction, transmission electron microscopy and energy dispersive spectrometry techniques. The results showed that the catalysts were highly active and selective to higher alcohols, and meanwhile stable for HAS. Characterization results indicated that Cu–Co was in the state of a solid solution alloy in the reduced catalysts, and the formation of Cu–Co alloy led to the high selectivity to higher alcohols. The elements in the catalysts were uniformly mixed and in interaction, thus sintering of the nanoparticles in the catalysts was restricted, resulting in a good stability. The high activity was mainly attributed to the high surface area and mesoporosity. Compared with Cu–Co/LaFeO₃ prepared by conventional methods, Cu–Co/LaFeO₃ with higher surface area and mesoporosity exhibited better activity and higher selectivity to higher alcohols. This design scheme may be applied to other bimetallic catalysts, and many transition metal ions can act as the lattice ions of perovskite-type oxides besides copper and cobalt.