Fluorescence enhancement of red and blue concurrently emitting Ba3MgSi2O8:Eu2+,Mn2+ phosphors for plant cultivation has been investigated by Dy3+ addition.The Ba3MgSi2O8:Eu2+,Mn2+,Dy3+(BMS-EMD) phosphors have two-color emissions at the wavelength peak values of 437 nm and 620 nm at the excitation of 350 nm.The two emission bands are coincident with the absorption spectrum for photosynthesis of plants.An obvious enhancement effect has been observed upon addition of Dy3+ with amount of 0.03 mol%,in which the intensities of both blue and red bands reach a maximum.The origin of red and blue emission bands is analysed.The photochromic parameters of the samples at the nearly UV excitation are tested.This fluoresence enhancement is of great significance for special solid state lighting equipment used in plant cultivation.
The sub-micron sized YAG ： Ce phosphors were synthesized via a modified sol-gel method by peptizing nano-pesudoboehmite particulate. It is found that YAG phase from the dried gel powders appears at 1000 ℃ then the pure YAG phase exists at a relatively lower sintering temperature of 1400 ℃. The smaller sizes of phosphors in the ranges of 1 - 3 μm are obtained due to the contribution of seeding effects of nano-sized alumina particles to strengthen each step of the processes. Both the excitation and emission spectra of photoluminescence of the phosphor obtained at 1400 ℃ meet well with the spectroscopic requirements of the WLED phosphors.
