Abstract Hydroxyapatite nanorods were synthesized with a new strategy by mixing hydrogen (15%) and argon (85%) gas injected into hydrothermal autoclave. Calcium nitrate tetrahydrate and diammonium hydrogen phosphate solutions were used as precursors. These materials were mixed together to maintain Ca/P ratio of 1.67. The final solution pH was adjusted with ammonia solution and transferred to the autoclave for hydrothermal process. The temperature and pH were set to 180 o C and 11 respectively. Powder synthesis was carried out once without gas injection, which was 10 h. The powders synthesized at 5, 10, and 15 h by injecting the gas mixture. The synthesized powders were characterized with Fourier transform infrared spectroscopy, Field emission scanning electron microscopy, X-ray diffraction, High-resolution transmission electron microscopy, and Raman spectroscopy. The results showed that use of injected gas increased crystallinity and crystallite size. Also, the use of gas injection has increased the hardness and elastic modulus.

中文翻译：

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水热法合成羟基磷灰石纳米棒的注气方法

摘要 通过混合注入水热高压釜的氢气 (15%) 和氩气 (85%)，采用新策略合成了羟基磷灰石纳米棒。四水合硝酸钙和磷酸氢二铵溶液用作前体。将这些材料混合在一起以保持 Ca/P 比为 1.67。最终溶液pH用氨溶液调节并转移到高压釜中进行水热工艺。温度和 pH 值分别设置为 180 o C 和 11。粉体合成一次，不注气，10 h。通过注入气体混合物在 5、10 和 15 小时合成粉末。合成的粉末通过傅里叶变换红外光谱、场发射扫描电子显微镜、X 射线衍射、高分辨透射电子显微镜、和拉曼光谱。结果表明，使用注入气体增加了结晶度和微晶尺寸。此外，注气的使用增加了硬度和弹性模量。