Biocompatible hydroxyapatite (HAp) powders have thermodynamically driven tendencies to lower their surface areas due to the formation of irreversible aggregates. To address this challenge, HAp hybrid powders are herein prepared by using a traditional wet-precipitation method with subsequent hydrothermal carbonization for surface modification. The crystallite size, crystallite degree and area ratio of the infrared peak assigned to bonding water against those of free water are determined to investigate the variation of HAp crystallization with processing parameters. The crystallization of HAp is facilitated by enriched water in a stealth layer with water molecules evolved by citrate, nitrogen (N)-containing methylene blue (MB), hydrogen-group-rich β-cyclodextrin (CD) and oxygen-containing organic carbon shells. The low surface areas result in fabrication of nano-sized HAp powders with a uniform size distribution, well-dispersed morphologies and smooth surfaces through calcination of HAp-CD-MB@C. The pH values of acidic buffers increase slowly during incubation of HAp-CD-MB@C powders with chemical stability and a large grain size after calcination at 550°C for 2 h. The present study will shed light on the preparation of nano-sized inorganic powders with a uniform size distribution, well-dispersed morphologies and modulated chemical stability for potential applications as carriers of small molecular substances and fillers in composite materials.

中文翻译：

---

具有更高化学稳定性和分散性的煅烧羟基磷灰石粉末

由于不可逆聚集体的形成，生物相容性羟基磷灰石 (HAp) 粉末具有热力学驱动的降低其表面积的趋势。为了应对这一挑战，本文通过使用传统的湿法沉淀法和随后的水热碳化进行表面改性来制备 HAp 杂化粉末。确定了分配给键合水与自由水的红外峰的微晶尺寸、微晶度和面积比，以研究 HAp 结晶随工艺参数的变化。隐形层中的富水促进了 HAp 的结晶，水分子由柠檬酸盐、含氮 (N) 的亚甲蓝 (MB)、富含氢基的 β-环糊精 (CD) 和含氧有机碳壳形成. 低表面积导致通过 HAp-CD-MB@C 的煅烧制备具有均匀尺寸分布、良好分散形态和光滑表面的纳米级 HAp 粉末。在 550°C 下煅烧 2 小时后，具有化学稳定性和大粒径的 HAp-CD-MB@C 粉末在孵育过程中，酸性缓冲液的 pH 值缓慢增加。本研究将揭示具有均匀尺寸分布、良好分散形态和调制化学稳定性的纳米级无机粉末的制备，作为复合材料中小分子物质载体和填料的潜在应用。在 550°C 下煅烧 2 小时后，具有化学稳定性和大粒径的 HAp-CD-MB@C 粉末在孵育过程中，酸性缓冲液的 pH 值缓慢增加。本研究将揭示具有均匀尺寸分布、良好分散形态和调制化学稳定性的纳米级无机粉末的制备，作为复合材料中小分子物质载体和填料的潜在应用。在 550°C 下煅烧 2 小时后，具有化学稳定性和大粒径的 HAp-CD-MB@C 粉末在孵育过程中，酸性缓冲液的 pH 值缓慢增加。本研究将揭示具有均匀尺寸分布、良好分散形态和调制化学稳定性的纳米级无机粉末的制备，作为复合材料中小分子物质载体和填料的潜在应用。