Dissolution–Precipitation Synthesis and Characterization of Zinc Whitlockite with Variable Metal Content
Agnė Kizalaitė, Inga Grigoravičiūtė-Puronienė, Dane Romar C. Asuigui, Sarah L. Stoll, Sunghun Cho, Tohru Sekino, Aivaras Kareiva, Aleksej Žarkov
Abstract
ions. Variable chemical composition of the synthesis products was achieved by changing Ca-to-Zn molar ratio in the reaction mixture. Investigation of the phase evolution as a function of time demonstrated that phase-pure zinc whitlockite powders can be synthesized in just 3 h. It is also demonstrated that single-phase products can be obtained when the Ca-to-Zn ratio in the reaction medium is in the range from 9 to 30. With higher or lower ratios, neighboring crystal phases such as scholzite or calcium hydroxyapatite were obtained. The morphology of the synthesized powders was found to be dependent on the chemical composition, transforming from hexagonal to rhombohedral plates with the increase of Zn content. Thermal stability studies revealed that the synthesized compounds were thermally unstable and decomposed upon heat treatment.