Fluorescence Properties and Synthesis of Green-Emitting Tb3+-Activated Amorphous Calcium Silicate Phosphor by Ultraviolet Irradiation of 378 nm

Abstract EN

The excitation wavelength of conventional Tb3+-activated phosphor is near 270 nm.

This study describes novel green-emitting Tb3+-activated amorphous calcium silicate by ultraviolet excitation at 378 nm.

The Tb3+-activated amorphous calcium silicate was prepared by heating a sample of Tb3+-activated calcium silicate hydrate (CSH) at 900°C for 30 minutes.

The emission wavelength of the resulting phosphor was 544 nm.

The optimum excitation wavelength within the range 300–400 nm was 378 nm.

The Tb3+-activated amorphous calcium silicate emitted green by ultraviolet irradiation.

The optimum initial Tb/Ca atomic ratio of this phosphor was about 0.5.

A mechanism for the action of the phosphor is proposed, in which Tb3+ ions existing in the layer of the CSH lead to loss of water molecules and OH groups.