Dye Encapsulated Metal-Organic Framework for Warm-White LED with High Color-Rendering Index

A strategy by encapsulating organic dyes into the pores of a luminescent metal-organic framework (MOF) is developed to achieve white-light-emitting phosphor. Both the red-light emitting dye 4-(p-dimethylaminostyryl)-1-methylpyridinium (DSM) and the green-light emitting dye acriflavine (AF) are encapsulated into a blue-emitting anionic MOF ZJU-28 through an ion-exchange process to yield the MOFdye composite ZJU-28DSM/AF. The emission color of the obtained composite can be easily modulated by simply adjusting the amount and component of dyes. With careful adjustment of the relative concentration of the dyes DSM and AF, the resulting ZJU-28DSM/AF (0.02 wt% DSM, 0.06 wt% AF) exhibits a broadband white emission with ideal CIE coordinates of (0.34, 0.32), high color-rendering index value of 91, and moderate correlated color temperature value of 5327 K. Such a strategy can be easily expanded to other luminescent MOFs and dyes, thus opening a new perspective for the development of white light emitting materials.