Optimization and photoluminescence behaviour of terbium doped YBO3 phosphors

Terbium doped yttrium borate phosphors have been prepared through solid state mixing method at 1200 degrees C. The concentration of Tb3+ ions has been varied in order to optimize the effective generation of green emission in Tb3+-doped yttrium borate phosphors. X-ray diffraction analysis suggested that the phase pure YBO3 was observed in all samples, and FESEM analysis confirmed that the particles were polyhedral and dumb-bell in shape. A detail photoluminescence behaviour of Tb3+-doped phosphors have been carried out under different excitation wavelengths. The PL behaviour suggested that the characteristic peaks due to Tb3+-ions appeared along with decrease in the broad peak intensity of the host with increase in the excitation wavelength. The optimum concentration of Tb3+ ions was found 5 and/or 10 mol % based on the PL behaviour. CIE coordinates suggested that the 5 mol % Tb3+-doped YBO3 sample has better chromaticity than that of other Tb3+-doped YBO(3 )phosphor compositions.