硼酸镁晶须的合成及表征

Synthesis and characterization of magnesium borate whisker

以氢氧化镁和硼酸为原料,利用高温-助熔剂-湿法工艺合成了高品质的硼酸镁晶须。采用XRD、SEM、HR-TEM、SAED等手段表征,系统研究了焙烧温度、焙烧时间、硼镁物质的量比及助熔剂添加量对晶须形貌的影响。结果表明,在焙烧温度为850℃、焙烧时间为4 h、n(硼)∶n(镁)=3∶1、n(钠+钾)∶n(镁+硼)=4∶1的条件下,可合成直径为0.5～0.8μm、长径比为40～240且表面光滑的硼酸镁晶须。还对硼酸镁晶须的高温-助熔剂-湿法工艺合成生长机理进行了探讨。

High-quality magnesium borate whisker was synthesized by high temperature-flux-wet method process with mag- nesium hydroxide and boric acid as raw materials.The synthesized samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high resolution transmission electron microscopy （HR-TEM）, and selected area elec- tron diffraction （SAED）.Effeets of calcination temperature,calcination time,amount-of-substance ratio of boron to magne- sium, and dosage of flux on whisker＇s morphology were investigated systematically.Results showed that smooth-faced magne- sium borate whisker with diameter of at 0.5-0.8 Ixm and aspect ratio of at 40-240 could be synthesized while calcination temperature was 850C ,calcination time was 4 h ,amount-of-substance ratio of boron to magnesium was 3：1 ,and dosage of flux was 4：1.Growth mechanism of magnesium borate whisker synthesized through high temperature-flux-wet method process was also discussed.