Preparation and characterization of Ce-W composite nanopowder

The synthesis of Ce-W composite nanopowder plays an important role in the preparation of relevant alloys. In the paper, the Ce-W composite nanopowder were prepared by liquid-liquid mixing, freeze drying, and two-stage reduction. The particle size of the powder produced is in the range of 20 and 30 nm. Homogeneous microstructure and uniform distribution of Ce were found in this powder. The phase compositions during the producing process of nanopowder were studied by XRD. The appearances of the freeze-dried powder, the first-reduced treated powder, and the finally obtained nanopowder were analyzed by SEM, FESEM, as well as TEM. Research results showed that most of the powders existed in the non-hygroscopic and non-crystalline state. The final product of the experiments was the W-Ce2WO6 nanopowder, which existed in the form of crystalline state. IR analysis indicated that the freeze-dried powder remained a Keggin structure. In addition, the TG and DTA thermal analysis explained that the losing water contained in the powders could be processed in three stages. (c) 2004 Elsevier B.V. All rights reserved.