Highly luminescent flexible amino-functionalized graphene quantum dots@cellulose nanofiber-clay hybrids for white-light emitting diodes

Amino-functionalized graphene quantum dots (afGQDs) made from graphene sheets glow bright with various colors under single-wavelength excitation, depending on their surface functional groups. These afGQDs were incorporated into a flexible and transparent clay host using electrostatic interactions between cellulose nanofiber (CNF) wrapped-afGQDs (CNF@afGQDs) and clay platelets. The resultant flexible afGQDs@CNF-clay films with a well-organized structure exhibited bright colorful photoluminescence, and were applied as a color converting material for blue light-emitting diodes (LEDs) to achieve white light emission. The af-GQDs@CNF-clay film based white LEDs showed pure white light emission with a CIE coordinate of (0.33, 0.37). The afGQDs@CNF-clay films with tunable emission are promising for use in future light emitting devices.