X-ray photoelectron spectroscopy characterization of copper–iron spinel as a catalyst for steam reforming of oxygenated hydrocarbon

Well-crystallized spinel CuFe2O4 in the tetragonal phase is obtained by calcination at 900 °C of the cubic CuFe2O4 prepared via a citrate sol–gel method. X-ray photoelectron spectroscopy coupled with Auger electron spectroscopy analysis reveals a high Cu1+/Cu0 ratio of ∼3/2 with negligible Cu2+ over the calcined CuFe2O4 subjected to in situ H2 reduction. The Cu1+-rich surface is considered to play a key role on the excellent catalytic performance in steam reforming of dimethyl ether for hydrogen generation.