Photoluminescence investigation of rare-earth activated GdCa3(GaO)3(BO3)4 phosphors under UV excitation

A borate compound was adopted as a new host material of Eu3+ and Tb3+ activators to fabricate efficient luminescence materials. The phosphor compositions, Gd1−xEuxCa3(GaO)3(BO3)4 and Gd1−xTbxCa3(GaO)3(BO3)4, were synthesized by conventional solid-state reactions. The crystalline phases of the resulting powders were identified using an X-ray diffraction system. Their photoluminescence properties were investigated under long-wavelength UV excitation. The Eu3+-doped and Tb3+-doped GdCa3(GaO)3(BO3)4 phosphors efficiently emitted red and green light, respectively. The temperature dependency of emission intensity was measured in a range from room temperature to 150 °C. The emission intensities of the red and green phosphors at 150 °C are 87% and 91% of those at room temperature, respectively. In addition, the decay times of both the red and green phosphors are shorter than 3 ms.