摘要
以CaCO3和CaHPO4·2H2O为前驱体,采用水热法制备了羟基磷灰石(HAP)晶体,利用X射线衍射(XRD)、扫描电镜(SEM)及X射线能谱分析仪(EDS)系统研究了pH值、水热温度、反应时间、Ca2+浓度等条件对合成HAP晶体微结构及晶体生长的影响,同时对其生长机理进行了探讨。结果表明:随着水热合成温度的升高、时间的延长、Ca2+浓度的增加,晶体发育越完整,HAP晶体的长径比呈增大趋势;体系的pH值对HAP晶体的生长有较大的影响,随着pH值的增加HAP晶粒的大小、长径比减小趋势明显;在水热温度为200℃,pH值=10,时间8 h的条件下,可得到结晶度高、晶形完整清晰,端面尺寸在50～70 nm,生长极性明显的六方柱状的一维n-HAP晶体。EDS分析结果证实合成的HAP平均钙磷比约为1.70左右,同理论值比较相符。点分析研究表明晶体端面的钙磷比比平均的略高,钙磷比约为1.75,从而证明了Ca2+的浓度直接影响着HAP晶体的极性生长。
Hydroxyapatite was synthesized by hydrothermal method with CaCO3 and CaHPO4 ~ 2H20 . The effects of pH value, reaction temperature, hydrothermal synthesis time and calcium ion concentration on the microstructure and the growth of HAP crystals were studied by the X-ray diffraction （XRD）, scanning election microscopy （SEM） and X-ray spectrometer （EDS）. Finally its growth mechanism was discussed. The results showed that the crystals grew more complete and the aspect ratio tended to increase with increasing hydrothermal synthesis temperature, time and calcium ion concentration. The pH value of the system have a greater impact on the growth of HAP crystals. With the increase of the pH value, the HAP crystal grain size and aspect ratio decrease significantly. High crystallinity and crystal clear of the growth polarity obvious hexagonal columnar one-dimensional n-HAP with the size of 40-50 nm was obtained under the condition of 200 ℃, pH = 11 for 8 h. EDS analysis results confirmed that the synthesis of HAP average Ca/P ratio was about 1.70, which consistented with theoretical values. Point analysis studies showed that crystal end face of Ca/P ratio slightly higher than the average, and Ca/P ratio was about 1.75, which proved that the concentration of Ca2~ has made a direct impact on the polar growth of HAP crystals.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2013年第9期1965-1971,共7页
Journal of Synthetic Crystals
基金
河北省科技厅支撑资助项目(10276732)
关键词
水热法
羟基磷灰石
微结构
生长机理
hydrothermal method
hydroxyapatite
microstructure
growth mechanism
