Single-Step Solid-State Synthesis of CeMgAl₁₁O₁₉:Tb Phosphor

Abstract

The green-emitting CeMgAl11O19:Tb (CMAT) phosphor has been prepared at 1200 °C by the simple solid-state reaction using AlF3 as a self-flux. This preparation temperature is much lower than those (1500-1700 °C) for conventional solid-state reaction and spray pyrolysis method. In particular, the complete process to produce high-quality phosphor particles was carried out through the single-step heat treatment of the mixture of corresponding oxide-type metal sources. An addition of AlF3 as a self-flux significantly decreased the crystallization temperature of CMAT with plate-like shape. The particle morphology could be controlled from plate-like to spherical by using H3BO3 as an additional flux. Thus, an optimal morphology and luminescence characteristics of CMAT were achieved when both AlF3 and H3BO3 fluxes were simultaneously used. Compared with conventional solid-state process, which is accompanied by the calcination step(s), and other alternative liquid solution techniques such as sol-gel method and spray pyrolysis, no use of active precursors and liquid media that are harmful to the environment is a distinctive advantage for the industrial purpose.

Comparison of experimental and theoretical radiation shielding parameters of several environmentally friendly materials

“…Terbium-doped cerium magnesium aluminate (CeMgAl 11 O 19 :Tb, CMAT) has been widely used as the green-emitting component in three-band lamps and has been studied for use in some PDPs [7,8]. In particular, it is used in long-life and highloading fluorescent lamps due to its high durability under intense UV radiation [9]. Sodium-yttrium-fluoride (NaYF 4 ), among all RE-doped fluoride host nanocrystals, is preferred for use in medical and biological fields due to & F. Akman fakman@bingol.edu.tr the noninvasive deep-tissue penetration of its radiation [10], its low toxicity [11], and its biocompatibility [12].…”