High resolution transmission electron microscopy investigation of single crystal apatite fibres synthesized by a homogeneous precipitation method

Apatite fibres were synthesized from aqueous solutions containing urea in the Ca(NO3)(2)-(NH4)(2)HPO4-HNO3 systems by a homogeneous precipitation method. The products were composed of carbonate-containing apatite fibres with preferred orientation along the (h00) planes. In order to characterise the properties of individual fibres, an investigation was performed using a high-resolution transmission electron microscopy (HR-TEM). It was confirmed, from the results of HR-TEM, that the apatite fibres were single crystals with the c-axis orientation parallel to the long axis of the fibre. In addition, the fibres were highly strained defects and consisted of domains that were preferentially oriented with the a-axis parallel to the surface of the substrate.