Nouvelle génération d'absorbeurs UV inorganiques.Etude de solutions solides oxydes et oxynitrures.Application à la protection du bois.

摘要

This research work aims at creating and finalizing a novel generation of efficient inorganic UV absorbers for the whole UV spectrum within rare earth-based oxide and oxynitride solid solutions. A progressive modification of the chemical composition results in a continuous variation of the absorption property. For example, starting from the colored perovskite-type oxynitride LaTiON and using the following cross-substitution: La + N = Sr + O, it is possible to shift the absorption edge towards lower wavelengths. A similar approach is presented in the case of fluorite-type oxide solid solutions. Non photocatalytic compositions absorbing at 400 nm (UV/Visible transtition) have been isolated in the ceria-based systems CeO-YWO and CeO-YO. Several chimie-douce routes have been developed to synthezise ultra fine powders in order to incorporate them in industrial transparent finishes applied to the protection of wood.