The effects of hydroxyl groups on Ca adsorption on rutile surfaces: a first-principles study
The effects of hydroxyl groups on Ca adsorption on rutile surfaces: a first-principles study
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羟基对金红石表面钙吸附的影响：第一性原理研究
DOI：
10.1007/s10856-009-3828-8
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发表时间：
2010-01-01
影响因子：
3.7
通讯作者：
Huang, Nan
中科院分区：
文献类型：
--
作者：
Lu, Xiong;Zhang, Hong-ping;Huang, Nan
钛表面的羟基被认为在吸收溶液中的钙方面起着重要的作用，而钙在体内和体外都是形成生物活性磷酸钙的关键。用第一性原理密度泛函理论(DFT)程序CASTEP研究了钙在不同金红石(110)表面的吸附，以阐明羟基对钙吸附的影响。在本研究中模拟的表面包括裸露的金红石(110)表面、羟基化的金红石(110)表面、氧化的金红石(110)表面以及由混合的羟基和水结合的金红石(110)表面。结果表明，并不是所有的羟基都有利于钙的吸附，在吸附过程中，疏松结合的羟基和金红石表面的水实际上与钙结合。氧化后的金红石表面对钙原子的吸附能力最强，这部分解释了碱处理的钛表面可以在碱性环境中诱导羟基磷灰石的形成。
Hydroxyl groups on titanium surfaces have been believed to play an important role in absorbing Ca in solution, which is crucial in the formation of bioactive calcium phosphates both in vitro and in vivo. CASTEP, a first-principles density functional theory (DFT) code, was employed to investigate Ca adsorption on various rutile (110) surfaces in order to clarify how hydroxyl groups effect Ca adsorption. The surfaces modeled in the present study include a bare rutile (110) surface, a hydroxylated rutile (110) surface, an oxidized rutile (110) surface, and a rutile (110) surface bonded with mixed OH groups and water. The results reveal that not all OH groups favors to attract Ca adsorption and loosely bonded OH and water on a rutile surface actually combine with Ca during adsorption. An oxidized rutile surface has the highest ability to attract Ca atoms, which partially explains that alkali-treated Ti surfaces could induce hydroxyapatite formation in alkaline environments.