Atomic arrangement analysis and crystal growth mechanism of HAp nanocrystal synthesized from amorphous calcium phosphate
Kouichi Nakashima, Sakino Misawa, Yoshio Kobayashi, Toru Ishigaki, Yoshihisa Ishikawa, Shu Yin, Masato Kakihana, Tomoyo Goto, Tohru Sekino- Materials Chemistry
- Ceramics and Composites
Abstract
The crystal growth of hydroxyapatite (HAp) using a solvothermal method was investigated under various reaction conditions. The purpose of the present study is the synthesis of HAp nanocrystals with multiple facets and the atomic arrangement for various orientations of the crystal was clarified. HAp nanorods were obtained at 200°C after 24 h using a reaction medium of water. The atomic arrangement in HAp nanorods was examined for a characteristic facet in the direction of [21−13−] and [0110−] incidences and crystal orientation along the c‐axis of HAp nanorod was confirmed using electron microscopy. The present study clarifies the HAp crystal growth mechanism, where the adsorption of cations or anions onto the crystal facet determines the HAp crystal shape. The crystals of HAp grew along the c‐axis and became rod‐shaped suggesting that cations were adsorbed predominantly over anions.