以硝酸钙和磷酸氢二铵为原料用化学共沉淀法制备纳米羟基磷灰石(n-HA)，用XRD、TEM 和BET表征样品的相组成、结晶形貌和比表面积. 结果表明：制备的针状羟基磷灰石长轴约为31.9nm，短轴约为21.3nm，粒径均匀且表面活性高，具有较低结晶度，比表面积高达135m2/g. 选用Ni2+作为吸附目标离子，通过Zeta电位、XRD和XPS分析n-HA吸附前后的表面电位、晶体物相和表面原子结合能的变化可知：Langmuir等温吸附模型仅适用于Ni2+初始浓度低于0.1mol/L的范围；当Ni2+初始浓度高于0.1mol/L时，Ni2+取代Ca2+与表面的O成键，吸附过程包括离子交换、静电吸附和溶解沉淀作用.
Nano-hydroxyapatite was prepared by chemical precipitation with Ca(NO3)2 and (NH3)2HPO4 as reagent. The phase composition, crystal morphology and specific surface area were characterized by XRD,TEM and BET. The results indicate that n-HA synthesized shows needlelike morphology with uniform average size of 31.9nm×21.3nm, week crystallinity, high surface energy, and the specific surface area of 135m2/g. Ni2+ is selected as adsorption object ion, the Langmuir adsorption isotherm is applicable when Ni2+ initial concentration is lower than 0.1mol/L, whereas when Ni2+ initial concentration is higher than 0.1mol/L, Ni2+ substitutes Ca2+ and binds with atom O on the surface. The adsorption of Ni2+ on nHA concludes ion exchange, electrostatic adsorption and dissolution-precipitation processes, This result is proved by the change on surface potential, crystal phase composition and binding energy of surface elements of n-HA before and after adsorption, which are analyzed by Zeta potential, XRD and XPS.
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