Studies on synthesis and properties of Zr1−Hf W2O8

Abstract

Abstract In this work, Zr 1− x Hf x W 2 O 8 ( x = 0, 0.2, 0.3, 0.4, 0.5, 0.6, 1) samples were successfully synthesized by fast solid state reaction for the first time. The appropriate temperature range and sintering time are 1573–1693 K and between 10 min to 60 min, respectively. This approach greatly reduces sintering time and energy wasting. The grain sizes are between 1 and 10 μm which is smaller than those by conventional solid state reaction. The structure and phase transition properties of the samples were studied by Raman spectroscopy and X-ray diffraction. The samples crystallized in cubic structure with space group P 2 1 3. The crystal cell parameters and volume decrease with the contents of Hf 4+ . But each mode position is between its corresponding mode positions of them. The internal vibrational modes shift to higher while the external modes shift to lower frequencies, and both gradually approach the mode positions of α-HfW 2 O 8 with the content s of Hf 4+ . The results suggest that the properties of Zr 1− x Hf x W 2 O 8 (0 x 2 O 8 and α-HfW 2 O 8 .