Synthesis and Calcination Temperature Dependent Photoluminescence Properties of Novel Bromosilicate Phosphors

Novel Eu2+-doped bromosilicate phosphors, (CaO–CaBr2–SiO2):0.03Eu2+, were prepared by the traditional solid-state method under a different calcination temperature. The as-prepared (CaO–CaBr2–SiO2):0.03Eu2+ phosphors obtained under various reaction temperatures all indicated a broad excitation in the near ultraviolet region (350–450 nm). The phosphor system exhibits bluish-green light with a peak wavelength at 498 nm when the calcination temperature is below 800 °C, while it shows a strong blue emission light with a peak wavelength at 474 nm as the calcination temperature is above 800 °C, and it also gives an interesting greenish-yellow long-lasting phosphorescence with a peak wavelength at 540 nm in the dark.