Artificial Light-Harvesting System with White-Light Emission in a Bicontinuous Ionic Medium

Artificial light-harvesting systems (ALHSs), which are closely related to Fo''rster resonance energy transfer (FRET), are among the most attractive scientific topics during the past few decades. Specifically, binary ALHSs that are composed of a fluid donor and acceptor have a simplified composition and high number density of the donor units. However, largely due to the difficulty in obtaining a fluid donor, investigation of these systems is still quite limited, especially for the ionic systems. Herein, we report a new type of binary ALHS using an ionic naphthalimide (NPI) derivative as a donor, which shows greatly improved photoluminescence for its bicontinuous liquid structure. When blending with an acceptor such as rhodamine 6G or trans-4-[4-(dimethylamino)styryl]-methylpyridinium iodide, efficient FRET was confirmed by both experimental results and molecular dynamics simulations, with an energy transfer efficiency up to similar to 90%. Tunable color, including white light emission, was achieved by tuning the acceptor/donor ratio, opening the door for a variety of applications such as light-emitting diodes and photoluminescent inks.

Automated summary

Artificial light-harvesting systems (ALHSs)are one of the most attractive scientific topics in recent decades. This study reports a new type of binary ALHS using an ionic derivative as a donor, which achieves efficient FRET and can be used for color tuning and various applications.