There has been a stringent demand for blue (~450-470 nm) absorbing and red(~611 nm) emitting material system in phosphor converted white light emittingdiodes (WLEDs) available in the market. Conventionally used red-emittingY2O3:Eu3+phosphor has negligible absorption for blue light produced by GaInNbased LED chip. To address this issue, a new red-emitting Gd2CaZnO5:Eu3+(GCZO:Eu3+) nanophosphor system having exceptionally strong absorption for blue(~465 nm) and significant red (~611 nm) photoluminescence (PL) is presented.This is attributed to a dominant f-f transition (5D0\rightarrow7F2) of Eu3+ions, aroused due to an efficient energy transfer from the Gd3+ sites of thehost lattice to Eu3+ ions. X-ray diffraction and microscopy observationsrevealed the nanocrystalline nature and a bit elongated morphology of thesample respectively. While the energy dispersive x-ray analysis identified thechemical constituents of the GCZO:Eu3+ nanophosphor, the color overlay imagingconfirmed the substitution of Eu3+ for Gd3+ ions. It is highly anticipated thatthe multifold absorption at ~465 nm would certainly improve the color renderingproperties of existing WLEDs.
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