NANOMETRIC POWDER

摘要

The invention relates to a method for the synthesis of a powder comprising primary particles having a maximum size of less than 250 nm, said method comprising the following consecutive steps: A) preparation of a mother liquor containing: an oxide having a monoclinic structure selected from HfO2, ZrO2, Eu2O3, Sm2Os or a precursor of said oxide having a monoclinic structure, and a modifying agent soluble in an aqueous medium selected from the group of oxoanions, anions of the elements of column 17 of the periodic table, hydroxide OH if the pH of the mother liquor is a base, and the mixtures thereof, the mother liquor having a pH of less than 4 or higher than 10, and B) preparation of said powder, including a hydrothermal treatment operation based on the mother liquor.