简介 |
PROBLEM TO BE SOLVED : To improve stability and to carry an NOx occlusion material in fine and highly dispersed state.
SOLUTION : Hydrogen peroxide is added to an aqueous solution of a compound oxide precursor comprising a first compound containing at least one kind of element selected from alkali metals, alkaline earth metals and rare earth elements, a second compound containing at least one kind of element selected from group 3 elements, group 4 elements and transition metals, and a third compound having a multidentate ligand. It is supposed that, by coordinating hydrogen peroxide in the complex made of the second compound and the third compound, the reaction between the complex and the ion of the first compound is suppressed and proceeding of gelation is suppressed. |