Single step synthesis of nano-sized NiO-Ce0.75Zr0.25O2 composite powders by glycine nitrate process

Abstract

Single step synthesis of NiO-Ce0.75Zr0.25O2 and Ce(0.75)Zr(0.25)O(2)powders was successfully achieved by glycine nitrate process (GNP). In this method, a precursor solution is prepared by mixing glycine with an aqueous solution of mixed (Ni, Ce-Zr) metal nitrates in the requisite quantities. The precursor was heated to evaporate excess water, yielding a honey-like liquid. Further heating the precursor at above 200 degrees C caused the precursor liquid to auto-ignite. Cubic fluorite nature of Ce0.75Zr0.25O2 and NiO phases was identified by XRD for the as-prepared samples. SEM and TEM analysis illustrate the foamy microstructural nature and the particle sizes of range 35-50 mn and 12-18 ran with a BET surface area of 5.5 and 29.2 m(2)/g for NiO-Ce0.75Zr0.25O2 and Ce0.75Zr0.25O2 powders respectively. Catalytic performance for partial oxidation of methane of NiO-Ce0.75Zr0.25O2 showed 58% methane conversion for a time period of 12 h with good H-2 and CO selectivity along with H-2/CO ratio of 2. (c) 2007 Elsevier B.V. All rights reserved.