Luminescent properties of a new green emitting Eu2+ doped CaZrSi2O7 phosphor for WLED applications

CaZrSi2O7 (CZS), a modification of the thortveitite family, was prepared as a polycrystalline powder material by the conventional solid-state reaction method. Structural, thermal and photoluminescence (PL) properties of the prepared material were investigated in order to evaluate its potentiality. XRD patterns confirm the monoclinic phase of CaZrSi2O7: Eu2+ phosphors.. Emissions arising from transitions between the 5d and 4f orbital gaps of Eu2+ are manifested in the broadband excitation and emission spectra with major peaks at 363 and 512 nm, respectively. The excitation wavelength matches well with that of the emission of the ultraviolet-light emitting diode (UV-LED). Concentration quenching occurs when the Eu2+ concentration is beyond 0.05 and the dipole–dipole interaction was the reason for the corresponding quenching mechanism. The temperature dependence of emission intensity of CZS: Eu2+ phosphor was investigated and it showed better thermal stability than the standard YAG: Ce3+ phosphor.