Effect of manganese source material on characteristics of Zn ₂SiO₄:Mn phosphor particles prepared by spray pyrolysis

The type of manganese material used as an activator source affected the luminous characteristics of Z₂SiO₄:Mn phosphor particles in spray pyrolysis. The prepared Zn₂SiO₄:Mn particles had different optimum post-treatment temperatures and reduction conditions for obtaining the maximum photoluminescence intensity from the manganese source material used. The particles prepared from manganese nitrate and sulfate had higher photoluminescence intensities than the commercial product prepared by solid-state reaction method after post-treatment at 1200°C without using a reduction process. However, the maximum photoluminescence intensity under vacuum ultraviolet excitation was obtained from the particles prepared from manganese chloride, post-treated at 1120°C for 5 h and reduced at 775°C, which was 10% higher than that of the commercial product. Manganese source material also affected the decay time (τ₁₀) of the Zn₂SiO ₄:Mn phosphor particles. The manganese chloride was favored for the formation of the phosphor particles having a short decay time and high brightness under vacuum ultraviolet excitation.