不同天然矿物制备纳米硅及微观形貌特征研究
Study on the Preparation of Nanosilicon from Different Natural Minerals and Microscopic Morphological Characteristics
李春生 1吴小贤2
作者信息
- 1. 浙江省地质院,浙江 杭州 310007;浙江省非金属矿工程技术研究中心,浙江 杭州 310007
- 2. 浙江省非金属矿工程技术研究中心,浙江 杭州 310007;浙江省海洋地质调查大队,浙江 舟山 316099
- 折叠
摘要
本试验以叶蜡石、蒙脱石、硅藻土和二氧化硅为前驱体,通过熔盐辅助镁热还原的方法制备不同形貌纳米硅材料.采用X射线衍射(XRD)、低温N2-吸附/脱附、扫描电镜(SEM)等研究不同矿物前驱体、金属镁添加量对制备多孔纳米硅的影响.结果表明,镁的加入量对纳米硅含量具有双相效应,适量的金属镁可促进前驱体中SiO2 的还原,然而当加入的镁超过一定量时,会导致纳米硅产率降低;蒙脱石前驱体中不同矿物的SiO2 在镁热还原过程中表现出不同的活性,SiO2 被还原活性顺序为蒙脱石>长石>石英;因蒙脱石与叶蜡石结构稳定性不同,在相同还原条件下,蒙脱石比叶蜡石更易被镁还原.不同硅前驱体制备的纳米硅材料在形貌和孔结构等方面存在差异,选择不同结构的前驱体,可获得形貌特异的纳米硅材料.
Abstract
In this study,silicon nanoparticles with different morphologies were prepared using pyrophyllite,montmorillonite,diatomite,and SiO2 as precursors,through a molten salt-assisted magnesiothermic reduction method.The effects of different mineral precursors and amounts of metallic magnesium on the synthesis of porous silicon nanoparticles were investigated using techniques such as XRD,N2 adsorption/desorption and SEM.The results show that the addition of magnesium has a biphasic effect on the content of silicon nanoparticles;an appropriate amount of metallic magnesium can promote the reduction of SiO2 from the precursors,but when the amount of magnesium added exceeds a certain limit,the yield of silicon nanoparticles decreases.SiO2 in different minerals of the montmorillonite precursor displays distinct activities during the magnesiothermic reduction:montmorillonite>albite>quartz.Under the same reduction conditions,montmorillonite is more easily reduced by magnesium compared to phyllosilicate,which may be related to montmorillonite's relatively lower structural stability.Silicon nanoparticles prepared from different silicon precursors exhibit variations in morphology and pore structure,and by selecting precursors with different structures,nanoparticles with unique morphologies can be obtained.
关键词
叶蜡石/蒙脱石/硅藻土/镁热还原/纳米硅Key words
pyrophyllite/montmorillonite/diatomite/magnesium thermal reduction/nanosilicon引用本文复制引用
基金项目
浙江省地质矿产研究所科技创新基金(ZD2020KJ01)
出版年
2024
NETL
NSTL
万方数据