摘要
采用一种基于气-固反应机制的模板限制镁热还原法,以SiO_2气凝胶为模板在低温(650℃)下制备出种高比表面积纳米多孔硅材料.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外(FTIR)光谱、X射线光电子能谱(XPS)和比表面积(BET)分析等表征手段对样品的成分、物相结构、微观形貌和孔结构进行分折,并初步研究了材料的光学特性和电化学性以.结果表明,产物为纳米硅晶体颗粒组成的多孔结构,保留了与原始气凝胶模板相似的微观形貌,比表面积高达602 m^2·g^(-1).该材料在室温下表现出显著的红光光致发光特性,且具有较高的储锂容量和较好的嵌入/脱出锂性能.
Novel nanoporous silicon was successfully converted from SiO_2 aerogels by a template-confined magnesiothermic reduction at low temperature（650℃） based on a gas-solid reaction. The composition,crystal structure,morphology,and pore structure of the samples were analyzed by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,Fourier transform infrared（FTIR） spectroscopy,X-ray photoelectron spectroscopy（XPS）,and Brunauer-Emmett-Teller （BET） surface area analysis.Their optical and electrochemical properties were also investigated.The results indicated that the products consisted of nanocrystalline silicon,retained a morphology similar to that of the original templates,and possessed a specific surface area as high as 602 m^2·g^（-1）.They also showed red photoluminescence at room temperature and had a high capacity and good Li-ion insertion/extraction properties for use in lithium ion batteries.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2011年第11期2719-2725,共7页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(51072137,50802064)
国家科技支撑计划(2009BAC62B02)
教育部新世纪优秀人才支持计划(NCET-08-0405)
教育部博士点基金(20090072110047,20100072110054)资助项目~~
关键词
多孔硅
模板限制
镁热还原
气凝胶
高比表面积
Porous silicon
Template-confined
Magnesiothermic reduction
Aerogel
High specific surface area
