The microstructure of scale formed by oxynitriding of Ti and exhibiting significant apatite-forming ability
The microstructure of scale formed by oxynitriding of Ti and exhibiting significant apatite-forming ability
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DOI：
10.1557/jmr.2016.79
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发表时间：
2016-03
影响因子：
2.7
通讯作者：
M. Hashimoto;S. Kitaoka;S. Muto;K. Tatsumi;Y. Obata
中科院分区：
文献类型：
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作者：
M. Hashimoto;S. Kitaoka;S. Muto;K. Tatsumi;Y. Obata
通过在含氧的氮气气氛中以极低的分压热处理Ti形成的氧化皮在模拟体液中表现出异常程度的羟基磷灰石（HAp）形成。扫描透射电镜和电子能量损失谱分析表明，氧化膜的亚表面是由氮掺杂的金红石型TiO_2组成。这一层的N-K边能量损失近边结构谱与用增广平面波加局域轨道带方法得到的可能化合物的理论谱相结合，表明氧位被两个氮取代，导致有效电荷为+2。这种垢的增强的HAp形成能力可能与由N的存在诱导的带正电荷的表面有关。相反，在空气中热处理形成的表面下的规模，其中没有发现N，导致慢得多的HAp覆盖，被认为是与缺乏表面电荷。
A scale formed by heat treatment of Ti in a nitrogen atmosphere containing oxygen at an extremely low partial pressure exhibited an exceptional degree of hydroxyapatite (HAp) formation in a simulated body fluid. Scanning transmission electron microscopy and electron energy loss spectroscopy indicated that the subsurface of this scale was composed of nitrogen doped rutile-type TiO_2. The N-K edge energy-loss near edge structure spectrum of this layer in conjunction with the theoretical spectra of possible compounds obtained using the augmented plane wave plus local orbital band method suggested that oxygen sites were replaced by two nitrogens, resulting in an effective charge of +2. The enhanced HAp forming ability of this scale is likely related to the positively charged surface induced by the presence of N. Conversely, the subsurface scale formed by heat treatment in air, in which N is not found, leads to much slower HAp coverage, believed to be related to the lack of surface charge.