稻壳制备哑铃状碳化硅晶须仿生模型

Preparation of dumbbell-shaped biomimetic SiC whiskers model from rice husks

将稻壳蒸煮后碳化为碳和二氧化硅,采用简单碳热还原法制备了仿动物骨骼的哑铃状碳化硅晶须(SiCw)仿生模型。通过X射线衍射、扫描电子显微镜等手段分析样品的组成、形貌。结果表明:最佳合成条件为:以3%Fe粉+2%NaF为催化剂,ωt(SiO2)=58.5%,先升温到1600℃成核,再降温到1500℃恒温时间3h。产物经XRD分析为较纯的β-SiCw,SEM观察表明,哑铃状SiCw的得率达90%以上。

Cooked rice husks were carbonized to C and SiO2.Then dumbbell-shaped biomimetic SiC whiskers model were prepared through a simple carbon-thermal reduction.The composition and morphology of the whiskers were analyzed by X-ray diffraction and electron microscopy.The experimental results showed that the optional synthesis condition were that adding 3% Fe＋2% NaF powder as catalyst,ωt（SiO2）=58.5%,firstly directly heating to nucleation temperature（1600℃）and then naturally dropping to 1500℃and keeping 3h;The crystal of whiskers is identified asβ-SiC by Xray diffraction method.The acquisition rate of the whiskers was more than 90%according to the results of SEM.