前驱体相对物质的量的变化对氢氧气相爆燃制备纳米SiO2颗粒的影响

以SiCl4为前驱体,以H2 和O2 的混合气体为爆源,通过改变前驱体的相对物质的量,考察前驱体 的相对物质的量对产物的影响。并通过XRF、TEM 和XRD等测量手段对纳米SiO2粉体进行测试分析:通过 XRF对产物进行成分分析,测得所得产物主要由SiO2组成,且纯度达到99.9%以上;由XRD结果得出,生成 的SiO2产物属于典型的不定形结构;由TEM 图片可以得出,生成的产物粒径大小大部分在50~100nm 之 间,且呈圆球状。随着前驱体相对物质的量的增加,所得到的产物粒子逐渐出现粘结,分散性下降,前驱体相 对物质的量应该控制在1.25以内。

Influences of relative amount of substance of precursor on nano-SiO2 particles prepared by oxy-hydrogen gaseous deflagration

Intheexperiments,theSiCl4liquidwiththepurityof99percentwaschosenasaprecursor andthegasmixturesofH2andO2asexplosionsources.Therelativemolarquantityoftheprecursor waschangedanditsinfluencesontheproductswereexplored.Andthenano-SiO2powderswerecharacterizedwithX- rayfluorescence(XRF)spectrometry,X-raydiffraction(XRD)andtransmissionelectronmicroscopy( TEM).TheXRFmeasurementshowsthattheobtainedproductismainlySiO2 anditspurityisabove99.9percent.TherelietypicalhalopatternsintheXRDspectraoftheproducts nearthediffractionangleof22degrees,indicatingthattheobtainedproductshaveamorphousstructures. The TEM images displaythatthe obtained main SiO2 powders have particlesizes of 50-100nmandarespherical.Withtheincreaseoftherelativemolarquantityoftheprecursor,the productsaregraduallyapttobondingandtheirdispersiondecreases.Sothemolarratiooftheprecursorshouldbecontrolledbelow1.25.