Effect of calcining temperature on particle size of hydroxyapatite synthesized by solid-state reaction at room temperature

•HAP powders were synthesized by solid-state reaction at room temperature.•The morphology of HAP crystals was strongly dependant on the calcining temperature.•The obtained powders calcining at 600 °C exhibit the morphology of platelets.

Using diammonium phosphate, calcium nitrate tetrahydrate and sodium bicarbonate as raw materials, hydroxyapatite (HAP) was facilely synthesized by solid-state reaction at room temperature. The crystallinity, phase, morphology and particle size of the products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry/differential thermal analysis (TG–DTA) and particle size analyzer. The influence of calcining temperature on the crystallinity and composition of HAP phase was also investigated.

Graphical abstractHAP powders were synthesized by solid-state reaction at room temperature. The results indicated that calcining temperature were critical in controlling the size and shape of the resulting HAP particles. When calcining temperature was higher than 600 °C, XRD analysis of resulting products revealed a single crystalline phase, similar to stoichiometric HAP.Figure optionsDownload full-size imageDownload as PowerPoint slide