A novel synthetic route to Y2O3:Tb3+ phosphors by bicontinuous cubic phase process

This study applies a novel approach to prepare the terbium-doped yttrium oxide phosphors (Y2O3:Tb3+) using the bicontinuous cubic phase (BCP) process. The experimental results show that the prepared precursor powder was amorphous yttrium hydroxide Y1-xTbx(OH)3 with a spherical shape and primary size 30-50 nm. High crystallinity phosphors with body-centered cubic structures were obtained after heat treatment above 700 oC for 4 h. The primary size of the phosphors grew to 100-200 nm, and dense agglomerates with a size below 1 μm were formed during the calcination. The obtained Y2O3:Tb3+ phosphor had a strong green emitting at 542 nm. The optimum Tb3+ concentration was 1 mol% to obtain the highest PL intensity. This study indicates that the calcining temperature of 700 oC needed for high luminescence efficiency in this work is much lower than 1000 oC or above needed for the conventional solid-state method.