Quantum Dots-Based Flexible Films and Their Application as the Phosphor in White Light-Emitting Diodes

Abstract

Flexible luminescent materials, with the advantages of foldability and crack resistance, have attracted extensive interest owing to their broad application in collapsible optoelectronic devices. In this work, highly luminescent and flexible films were fabricated via self-assembly of triple building blocks: layered double hydroxide (LDH) nanoplatelets, polyvinyl alcohol (PVA), and quantum dots (QDs: CdTe or CdSe/ZnS), which show 2D ordered structure and finely tunable fluorescence (green, yellow, orange, and red). The resulting films display rather strong fluorescence and high fluorescence quantum yield (PLQY), which can be attributed to the uniform dispersion of QDs within the inorganic–organic hybrid matrix. Furthermore, we incorporated the red-emitting LDH/(PVA-CdSe/ZnS) film with the commercialized white light-emitting diodes (WLED) and obtained significantly improved color-rendering property through modifying its spectral distribution. In addition, the LDH/PVA-QDs films display high photo- and thermostability. Therefore, this work provides a facile approach for the design and fabrication of clay–polymer–QDs hybrid luminescent films with exceptional light emission, flexibility, and stability, which can serve as promising materials for the integration of WLED illumination devices.