Formation of tetragonal hydrogen tungsten bronze by reactive mechanical alloying

Hydrogen tungsten bronzes have been synthesized by reactive mechanical alloying monoclinic tungsten (VI) oxide under hydrogen atmosphere. Two milling devices with different energy ranges were used. Regardless of the distinct reaction times, a similar phase evolution was observed with both apparatus. The characterization of the materials was performed by XRD, SEM, DSC and total hydrogen content determination. The final product obtained was a mixture of tetragonal H0.33WO3 and H0.23WO3 bronzes. (C) 2007 Elsevier Inc. All rights reserved.