Glycothermal synthesis and photoluminescence of Mg-Si modified Ce:YAG nanophosphors.

The absorption spectrum of Ce in a YAG based host grown using the glycothermal method was modified using the addition of Mg-Si pairs. Photoluminescence intensity was dramatically improved by increasing the reaction temperature to 315 °C instead of the conventionally used 300 °C. It was found that Mg acetate and tetraethylorthosilicate (TEOS) are suitable as precursors for the glycothermal process, as EDS elemental mapping showed their homogeneous inclusion in the final product. Their addition only slightly modified the emission spectrum of Ce:YAG. It was found that increasing the reaction temperature to 315 °C yielded nanoparticles 56 ± 16 nm in size with a 3.3× enhancement in absorption and 3.7× enhancement in emission intensities compared to samples synthesized at 300 °C, and an increase in photoluminescence quantum yield from 32% to 48%. Reaction kinetics of the precursors and a proposed route for post-synthesis surface functionalization are discussed.