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Structure transition from aragonite to vaterite and calcite by the assistance of SDBS

“…Pure aragonite and a mixture of aragonite and a trace amount of calcite were fabricated without any organic additives at 90 and 120 • C, respectively [13]. In the present investigation, a mixture of aragonite and a trace amount of calcite was synthesized at 150 • C. The obtained results prove that the effect of experimental temperature on polymorph of crystal CaCO 3 is not obvious between 120 and 150 • C. The transformation from aragonite to calcite was reported by through the agitation during the product formation process [16,17]. In the present work, SDBS was employed to modify the polymorph of crystal CaCO 3 .…”

Preparation of Uniform Needle-Like Aragonite Particles by Homogeneous Precipitation

“…The rate of these processes can be carefully controlled, which made it possible to establish conditions that would result in the formation of uniform aragonite particles by homogeneous precipitation in calcium salts solutions (18). In other studies irregular aragonite particles were obtained, if carbonate ions were introduced by CO 2 or soluble carbonate salts (13,6).…”

“…For example, aging the solution under magnetic stirring produced well-defined rhombohedral calcite particles. The transformation might proceed through a dissolution and recrystallization mechanism, controlled by surface reactions (6). According to Kato and co-workers (18), agitating reacting solutions with a magnetic stirrer yielded first aragonite, which then transformed into calcite.…”

“…Direct inorganic precipitation using soluble carbonate and calcium salts as initial materials produced irregular aragonite crystals (5,6). This method was modified by doping calcium salt solutions with small amounts of Sr 2ϩ , Ba 2ϩ , and Pb 2ϩ (7)(8)(9).…”

New Synthesis Technique for Making Hydroxyapatite Ceramics Using Hydrothermal Hot-Pressing.

“…This technique is applied to solidify many kinds of the materials such as silicate glass, titania, calcium carbonate, hydroxyapatite, etc [12,13].…”