Surface adaptation prompted enhanced photo and thermoluminescence properties of Dy3þ doped wollastonite nanophosphor

Abstract

The novel CaSiO3:Dy3þ (1–11 mol %) nanophosphors synthesized via simple solution combustion route and covered with silica (SiO2) by the St€ober method are reported in the present work. The X ray diffraction analysis verifies the phase purity of the synthesized samples. The diffraction peaks observed in the recorded powder x-ray diffraction patterns are in good relation with those known for the CaSiO3 structure. The photoluminescence and thermoluminescence properties of SiO2@CaSiO3:Dy3þ (3 mol %) nanophosphors were extensively investigated. The 3-fold enhancement in the photoluminescence intensity of nanophosphors after surface coating was observed, that may be due to light diffraction and multiplied by shell SiO2. The utility of the prepared samples in white light emitting diodes was confirmed by studying photometric properties. The thermoluminescence study of the samples with different γ-ray doses showed good linearity up to 4 kGy and, thereafter, the sub-linear behavior was noticed. The variation in the thermoluminescence intensity arises as a consequence of competition between different trapping centers. The aforementioned results signify that the present material was highly useful for display and dosimetry applications.