Photoluminescence properties of Mgq2 and its ex-situ, in-situ composites with PVOH

Abstract

Most of the metal quinolate have broad excitation spectra is in range 385nm to 410 nm with emission spectra in the blue green region and hence can be easily pumped by the UV and near UV LEDS. However the emission efficiency is significantly low to make them suitable for any practical applications. Blending quinolates with polymers not only make them highly emissive but the emission and excitation can be tailored according to the requirement. Moreover the properties changes with the way in which blend is prepared, which are labeled as In-situ blending and Ex-situ blending. In In-situ blending the Mgq2 is prepared in the polymer solution itself whereas in Ex-situ blending the previously prepared Mgq2 powder is dissolved in suitable solvent and mixed with the polymer. In this paper we report photoluminescence properties of Mgq2 and its composite film with PVOH. Green Yellow emission in Mgq2 powder is observed when excited by 385 nm LED whereas intense green emission is observed when excited by 400 nm LED. An Intense emission is observed in Mgq2 Ex-situ composites and observed emission is 7 times more with respect to powder. The Ex-situ composite shows near white emission when excited by 385 nm LED whereas blue green emission is observed when excited by 400 nm LED. In In-situ composites near white emission is observed when excited by 385 nm whereas blue emission is observed when excited by 400 nm LED. Thus these blended polymers may find application as white light phosphor for PCLED applications using near UV LEDs.