Molten salt synthesis of morphology controlled α-alumina platelets

摘要: Abstract Controlling the morphology of plate-like α-Al 2 O 3 powders is essential since Al platelets different sizes and shapes are needed in numerous applications. In this work, non-aggregated single-crystal with diameters ranging from ~1 µm to more than 20 µm thicknesses ~0.1 µm 1.3 µm were produced by molten salt synthesis. The effects alumina precursor compositions on phase formation development particles investigated. (SO 4 ) reacts K SO form Al(SO liquid at ~625 °C. seeds generated in-situ decomposition can serve as low energy nucleation sites, thus accelerate complete transformation much lower temperatures, yielding ≥20 µm diameter. Conversely, γ-Al stable until higher resulting small hexagonal (1–2 µm diameter) salt. addition precursors, species also strongly affect particles. Compared chloride salts (NaCl KCl), sulfate (K Na create favorable conditions for growth higher- aspect-ratio platelets.