Electrochemical synthesis and characterization of hydroxyapatite powders

Electrochemical synthesis of hydroxyapatite powders was performed galvanostatically from homogeneous solution of Na2H2EDTA·2H2O, NaH2PO4 and CaCl2 at a concentration relationship Ca/EDTA/PO43− of 0.25/0.25/0.15 M at current densities of 137 and 207 mA cm−2 and pH values of 9.0 and 12.0. The hydroxyapatite powders were characterized by X-ray diffraction, size distribution measurements, transmission electron microscopy, scanning electron microscopy and thermogravimetric and differential thermal analysis. The influence of the electrochemical synthesis parameters, e.g. applied current density and pH value, on the phase composition, crystallite size, morphology and thermal characteristics of hydroxyapatite powders were investigated.