Electron−Phonon Coupling from a Nanocomposite of Perovskite Quantum Dots and Nematic Liquid Crystal for White LED

Abstract

Here, we report the photophysical properties of a nanocomposite composed of CsPbBr3 (or I) quantum dots and a nematic liquid crystal (5CB). The liquid crystal (5CB) acts as a cationic-like spacer that effectively arranges the quantum dots (QDs). Temperature-dependent photoluminescence (PL) was used to investigate the optical properties of QDs/5CB nanocomposite films. The liquid crystal modulates the electron−phonon coupling strength and exciton binding energy of the perovskite, providing an effective means to control the arrangement of perovskite QDs. Notably, thin films of the nanocomposite exhibit unique and intriguing absorption and emission characteristics. We also present data on voltage-driven switching between the anisotropic limits. Furthermore, we propose a tandem device architecture based on stacked red, green, and blue (RGB) LED chips for full-color lighting and display applications. These nanocomposite and device strategies offer a viable pathway toward advanced lighting and white LEDs.