Supercritical fine particle synthesis method and fine particles of barium hexaferrite

摘要

PPROBLEM TO BE SOLVED: To provide ultrafine and monodispersed crystalline nanoparticles of barium hexaferrite, which are scientifically and technologically very important particles, by precisely controlling its shape and size. PSOLUTION: A barium hexaferrite single magnetic domain nanoparticle having controlled size and shape obtained by capping with an organic ligand using an SCW flow reactor aided with an organic molecule, and its simple and economically excellent production method are provided. The formation and controlled growth of colloidal nanoparticle of barium hexaferrite occurs under a supercritical water (SCW) condition by (1) firstly, mixing supercritical water and a precursor liquid at a mixing point to form a single nanocrystal, (2) next, mixing an organic molecule with high temperature water, and (3) lastly, reacting selectively the organic molecule and the surface of a specific inorganic crystal. PCOPYRIGHT: (C)2009,JPO&INPIT