单分散纳米二氧化硅的制备与表征

Synthesis and Characterization of Monodisperse SiO_2 Nanoparticles

利用Stober溶胶-凝胶法,合成了大小约为80～150nm的单分散纳米二氧化硅微球,并且探讨了温度、氨水浓度以及TEOS浓度等因素对合成二氧化硅的影响。利用XRD、IR、SEM、TEM等手段对样品进行了表征。结果表明：水解温度的升高加速二氧化硅颗粒在溶液中的熟化引起团聚;氨水浓度的增加使得成核速度增加,水解速度加剧,二氧化硅的粒径增大,团聚程度也增大。TEOS的量的增加也导致二氧化硅粒径稍有增加,团聚程度加深。

A StOber Sol-gel method has been used to prepare monodisperse and uniform-size from 80～150 nm silica nanopartieles in this paper. The silica particles were obtained by hydrolysis of tetraethyl orthosilieate （TEOS） in ethanol medium use ammonium as catalyst and a detailed study was carried out on the effect of different temperature, amount of ammonium and TEOS on particle sizes and the dispersion. The structure of the sample was examined by XRD and the chemical bond of the sample surface was examined by FT- IR. The particle size and the dispersion were examined under scanning electron microscopy and transmission electron microscopy. The results obtained in this study showed that the high hydrolysis temperature speed up the SiO2 conglomeration in the solution. More over, the particle size and the dispersion of SiO2 obtained were increasing with the increasing of amounts of ammonium and TEOS which attributed to the reason that the hydrolysis speed and nucleation speed was increasing.