Effect of pH control of mixture solution on the fabrication of the highly pure β-tricalcium phosphate powders synthesized by liquid-solid mixture precipitation method

摘要

The β-tricalcium phosphate (β-TCP; Ca_3(PO_4)_2) powders with high purity could be attained through mixing and precipitating (NH_4)_2HPO_4 with solution state and Ca(NO_3)_2·4H_2O with solid state and controlling the pH of mixture solution in a range from 7.0 to 8.5 within a short time. The FT-IR results showed that the peak of calcium pyrophosphate (Ca_2P_2O_7) excluding the peaks associated with p-TCP appeared at a pH ranging from 5.0 to 7.0 but did not appear at a pH ranging from 7.0 to 8.5. It is considered that the phase purity of β-TCP powders could be significantly improved through liquid-solid mixture precipitation and pH control of mixture solution. The XRD and SEM results showed that the phase purity and the particle size of precipitated β-TCP powders were above 99% and ranged from 200 nm to 600 nm, respectively.