ABSTRACT
We successfully synthesized the green-emitting Y2SiO5:Tb3+ (YSO:Tb3+) phosphors using a improved solid-state-reaction method and characterized the resultant phosphors employing X-ray diffraction and Scanning Electron Microscope (SEM) techniques. The photoluminescence (PL) of the prepared YSO:Tb3+ (0.1–2 mol%) were investigated. The main emission peak of the phosphors was at 549 nm under a 243 nm of excitation due to the 5D4–7F5 transition of the Tb3+, whereas the peak at 485 nm was due to the 5D3–7FJ transition. With the different doping concentrations, the PL-emission intensities correspond to the peaks at 485 and 549 nm increased upto 1.5 mol% Tb3+ doping concentration and then decreased due to concentration quenching. The Commission Internationale de I’Eclairage coordinates of the YSO:Tb3+ were calculated and found in the deep green region. This result denotes that the present phosphor might be useful in solid-state lighting as well as in the display-device applications for the green light emission. We irradiated the prepared samples by UV rays with a 254 nm wavelength for the investigation of thermoluminescence (TL). The TL presented a well-resolved higher temperature peak at 148 °C with one associated shoulder peak at 107 °C. The peak at higher temperature displayed greater stability and less fading in the prepared phosphors. These phosphors may be useful for dosimetric applications.
