Catalytic activity of ultrafine CexGdySmzO2 synthesized by metal organic complex method toward steam reforming of methane

CexGdySmzO2 synthesized by metal organic complex method has useful methane steam reforming activity under moderate temperatures. This preparation technique offers materials with fluorite structure and ultrafine particle (having particle sizes less than 106.54 nm after calcined at 900 degrees C). Among the materials with various Ce/Gd/Sm ratios, Ce0.8Gd0.05Sm0.15O2 showed the highest reforming rate (102.9 mol(CH4) kg(-1) h(-1)) compared to 23.1 mol(CH4) kg(-1) h(-1) observed over undoped-CeO2. This good performance was proven to relate with the improvements of oxygen storage capacity (OSC) and lattice oxygen mobility by Sm- and Gd-doping, according to the temperature programmed reduction/temperature programmed oxidation (TPR/TPO) and O-18/O-16 isotope exchange studies. (C) 2010 Elsevier B.V. All rights reserved.