Synthesis of pure Zn2SiO4 : Mn green phosphors by simple PVA-metal complex route

Green light emitting Zn2-x Mn (x) SiO4 (willemite) particles were synthesized by a simple and cost-effective poly(vinyl alcohol) (PVA)-complex route. Microstructural studies on the calcined products show that particles are pure, single phase, nano-crystalline, and agglomerated morphology. A pure-phase willemite structure was obtained with calcination between 850 and 1,175 degrees C for 2 h in air. Particle size analysis indicates that the average particle size is similar to 1 mu m. The photoluminescence properties of these 4 and 12 mol% Mn-doped Zn2SiO4 powders were measured by fluorescence spectroscopy. Particles with 4 mol% Mn doping prepared at 1,150 degrees C, with an emission decay time, I (0)/e, of 13.4 ms showed the highest relative peak emission intensities. The emission intensity at this doping level was measured to be similar to 110% of a representative commercial product's, doped with 11.2 mol% Mn, and exhibiting a decay time of 7.1 ms. The effect of calcination temperature on the photoluminescence and crystallinity properties of synthesized green powders was also investigated.