SiO_2包覆的羟基磷灰石纳米粒子的制备与性能研究

Research on preparation and property of silica-coated HAP particles

采用正硅酸乙酯(TEOS)水解法在羟基磷灰石粉体表面包覆SiO2进行表面改性,并通过扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、红外(FT-IR)、zeta电位和沉降实验等对样品的晶体结构、颗粒形貌进行了表征,结果表明涂层厚度约为3nm,包覆后的纳米粒子在水溶液中的胶体稳定性提高了5倍,SiO2在羟基磷灰石表面的吸附符合异质凝结机制。

Nanophase hydroxyapatite（HAP） particles were coated with silica via the hydrolysis of tetraethyl orthosilicate（TEOS）.The nanocomposite particles were characterized by transmission electron spectroscopy（TEM）,scaning electronmicroscopy（SEM）,X-ray diffraction（XRD）,Fourier transform infrared（FT-IR） spectroscopy,sedimentation timeand zeta potential（ζ） studies.A sequential changes in infrared spectral features characteristic of HAP was accompanied by an increase in features characteristic of silica as revealed by FT-IR.The silica coating enhanced the colloidal stability of HAP in aqueous suspensions.This behavior can be explained based on a heterocoagulation coating mechanism in which silica clusters adsorb onto the HAP particle surface.