Recent developments in morphological control of α-Al₂O₃particles synthesized in 1,4-butanediol solution

Direct precipitation of metal oxides from high boiling point organic solvents presents an alternative to wholly aqueous hydrothermal material synthesis routes. In the current study, reaction conditions to control particle size and shape of α-alumina, precipitated from 1,4-butanediol solutions are described. Synthesis variables including reaction time, stirring speed, amount of methanol, and solid loading have a strong effect on the size and shape of α-alumina synthesized in 1,4-butanediol solutions conditions to prepare α-alumina crystals with different habits including circular platelets, hexagonal platelets, hexagonal platelets with habit modifications on the edges, dodecahedra, polyhedra with 14 faces, polyhedra with 20 faces, hexagonal prisms, and hexagonal prisms with habit modifications on the edges are presented. Possible growth mechanisms of α-Al₂O₃particles in 1,4-butanediol solution are proposed based on theoretical shape and atomic surface structure generated with programs SHAPE^©and ATOMS^©. The results of this study indicate that it is possible to control the morphology of synthesized α-alumina particles by controlling the process conditions, and theoretical predictions of crystal shapes can be reconciled to the morphology of the experimentally synthesized particles.