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用水热法并经570℃热处理6h制备了ZrW2O8粉体,对水热法制备的前驱体进行了热重–差热分析。用X射线粉末衍射、扫描电子显微镜对ZrW2O8粉体的微观结构及形貌进行表征,结果表明:ZrW2O8粉体为单一α-ZrW2O8相,粉体颗粒为规则的长方体棒状,尺寸约为1.2μm×1.2μm×10μm。原位X射线粉末衍射分析表明:所得ZrW2O8粉体具有很好的负热膨胀特性,从室温到500℃,其热膨胀系数为–6.30×10–6℃–1;在150～175℃温度范围内发生了α-ZrW2O8向β-ZrW2O8相的转变。
The ZrW2O8 powder was prepared by hydrothermal method and heat treatment at 570 ℃ for 6h. The hydrothermal-differential thermal analysis of the precursor was carried out. The microstructure and morphology of ZrW2O8 powder were characterized by X-ray powder diffraction and scanning electron microscopy. The results showed that the ZrW2O8 powder was a single α-ZrW2O8 phase with a regular rectangular parallelepiped rod shape with a size of about 1.2μm × 1.2 μm × 10 μm. In-situ X-ray powder diffraction analysis showed that the obtained ZrW2O8 powder has good negative thermal expansion characteristics, which range from room temperature to 500 ℃ and its thermal expansion coefficient is -6.30 × 10-6 ℃ -1. It occurs within the temperature range of 150-175 ℃ The transformation of α-ZrW2O8 to β-ZrW2O8 phase was investigated.