Facile synthesis of single phase α-Zn2SiO4:Mn2+ phosphor via high-energy planetary ball milling and post-annealing method

Abstract

α-Zn2SiO4:Mn2+ green emitting-phosphor was prepared by a high–energy planetary ball milling and post-annealing method. The effect of Mn2+ doping concentration and annealing temperature on optical properties of the phosphors were systematically investigated by using XRD, FESEM, FTIR, Raman, Photoluminescence (PL) and Thermoluminescence (TL) spectroscopy. XRD results indicate that single crystalline α-Zn2SiO4:Mn2+ phosphor could be obtained after a thermal treatment at 1250 °C. The PL spectrum of the undoped Zn2SiO4 sample showed two emission bands: a strong broad NIR band centered at 740 nm and a weak green band centered at 520 nm, which are respectively attributed to NBOHs interface defects and other defects in the host crystal. The PL spectrum of Mn2+-doped α-Zn2SiO4 phosphor exhibited a single intense green emission band centered at 525 nm due to the electronic transitions 4T1-6A1 of Mn2+. The TL glow curve shows a strong peak at 158 °C and a weak peak at 235 °C, and shows a linear dose response with β-ray exposure time, which indicates the phosphor may be useful for dosimetric application.