DOI: 10.3724/SP.J.1249.2020.03298
锶(Sr)是人体含有的微量元素之一,研究锶掺杂羟基磷灰石复合物对于骨修复有重要意义.采用Ca(NO3)2·4H2O溶液作为钙源,Na2HPO4作为磷源,加入适量Sr(NO3)2溶液以及石墨烯粉末,通过水热法合成锶掺杂羟基磷灰石-石墨烯(Sr-doped hydroxyapatite-grapheme, Sr-HA-GP)复合材料.利用傅里叶变换红外光谱仪、X射线衍射仪、场发射扫描电子显微镜、透射电子显微镜、X射线能量色散仪和拉曼光谱仪等,对该复合材料的表面形貌、物相组成和结构等进行表征和研究.结果表明,Sr2+被成功掺入HA晶格中,低比例Sr2+掺杂复合材料整体形貌较好,而高比例Sr2+掺杂不仅会影响HA结晶度、改变其形貌、产生无定形相,而且会使HA颗粒出现团聚现象.同时,在水热过程中Sr-HA-GP复合材料的HA与GP界面间发生相互作用,各自结构都发生了变化. 研究结果表明,Sr2+掺杂量增加倾向于抑制HA微晶的生长,从而在石墨烯表面形成低结晶度的HA晶粒, 而且 Sr-HA与GP之间的复合并不是单纯的物理混合,而是发生了某种键合作用.
Sr is a trace element in human body. It is very important to study Sr-doped hydroxyapatite composites for bone repair. In this study, we use Ca(NO3)2·4H2O solution as calcium source, Na2HPO4 as phosphorus source, and mix with appropriate Sr(NO3)2 solution and grapheme powder to prepare Sr-doped hydroxyapatite-graphene(HA-GP)composites by hydrothermal method. Then, we characterize the surface morphology, phase composition and structure of the composites by Fourier transform infrared(FTIR)spectroscopy, X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), transmission electron microscopy(TEM), energy-dispersive X-ray spectroscopy(EDX)and Raman spectroscopy(Raman). The results indicate that Sr ions can be doped into the HA crystal lattice successfully. It exhibits good morphology when small amount of Sr ions is doped, while high concentration of Sr-doping not only affects the crystallinity of HA, changs its morphology, produces the amorphous phase, but also makes HA particles form the agglomeration. Meanwhile, the interface between HA and GP appears interactions during the hydrothermal process of Sr-doped HA-GP composites, and results in respective structural changes. The results show that the increase of Sr doping tends to inhibit the growth of HA microcrystals, thus forming HA grains with low crystallinity on the surface of graphene. Moreover, the combination of Sr-HA and GP is not just a physical mixture, but a chemical bonding.
