Homogeneous coatings of nanosized Fe_(2)O_(3) particles on Y_(2)O_(2)S:Eu

摘要

The red emitting phosphor Y_(2)O_(2)S:Eu commonly applied in colour television tubes was pigmented with a thin homogeneous layer of nanosized Fe_(2)O_(3) particles based on a novel coating strategy. In a first step the phosphor was covered with nanosized Fe_(3)O_(4) particles which themselves were prepared by reduction of an Fe(III)-salt with hydrazine. Thereafter, Fe_(3)O_(4) was converted to Fe_(2)O_(3) by heating to 450℃ in air. Surface composition and body colour of the corresponding phosphor samples were investigated applying ESCA and measuring diffuse reflectance. The size of the Fe_(2)O_(3) particles as well as the homogeneity of the resulting coating were studied by SEM. Furthermore, the adhesion of Fe_(2)O_(3) particles on the phosphor surface was examined.