Spectral variation of Y3Al5O12:Ce3+ nanophosphors and their optical simulation

Yellow Y3Al5O12:Ce3+ (YAG:Ce) nanophosphors were prepared through a high-energy planetary milling of the bulk phosphor: two groups of D50 = 200 nm and 500 nm. They showed the drastic narrowing of excitation peaks with blue-shifting of emission bands, indicative of smaller spectral overlap and Stokes shift, compared with the bulk. It was explained by their significant quenching of all Raman scattering modes, implying the restriction of electron-phonon couplings caused by their defects. The optical simulations of white LEDs based on the nanophosphor's mixture with K2SiF6:Mn4+ red phosphor showed a higher color rendering index for their smaller concentrations.