Facile fabrication of spherical silicone encapsulant with Pt nanoparticles for applications as white light-emitting diode

In this letter, optical performances of white light-emitting diode (LED) packages, based on silicone encapsulants with geometries of sphere and hemisphere, were investigated. The spherical encapsulant has a high potential for directing light and was prepared facilely by adding the Pt nanoparticles (PtNPs) obtained through thermal decomposition. Such silicone encapsulant with PtNPs containing well-dispersed phosphor particles was achieved in comparison to the hemispherical encapsulant with unfavorable distribution of phosphor. Under 7 wt% phosphor incorporation and 350 mA injection, the white LED packaged with spherical encapsulant delivers a significantly higher luminous efficacy of 105.9±2.9 lm/W with reference to the performance of hemisphere-shaped white LED package (87.8±2.0 lm/W).