Electrophoretic Deposition Behavior of Sol-Gel Synthesized Hydroxyapatiteand Tricalcium Phosphate Nano-Powders

Recently, hydroxyapatite and β-tricalcium phosphate coatings have been used as bonding layerson implants in medical applications. In this research, nano-powders of calcium phosphateceramics were synthesized by sol-gel route. Calcium nitrate and dihydrogen phosphate were usedas precursors. Deionized water and ammonia were also employed as solvent and pH adjuster,respectively. The prepared sol was aged at room temperature and transformed to a white gel.Finally, hydroxyapatite and β-tricalcium phosphate were obtained by heat treatment at differenttemperatures. Then, these nano-powders were electrophoretically deposited on stainless steelsubstrate by applying ۱۲۰ V for ۱۰ min. Crystalline phase characterization was done by X-raydiffraction (XRD) and the results were confirmed by energy dispersive X-ray (EDX). Suspensionof each nano-powder was prepared in two different media and the dispersion behavior of eachcolloid was investigated. Based on dispersion behavior results and scanning electron microscopy(SEM) images, ethanol and ۲-propanol are the best media for electrophoretic deposition ofhydroxyapatite and β-tricalcium phosphate, respectively.

Keywords:

Hydroxyapatite , Tricalcium phosphate , Sol-gel , Electrophoretic deposition