Abstract: Systems and methods for an active emissive layer configured for use in an electroluminescent device. The active emissive layer includes a host-guest blend in which the host includes a perovskite (e.g., CsPbBr3, CsPbCl3, and/or CsPbI3) and the guest includes quantum shells (QSs) embedded in the host. The QSs include a quantum-confined, spheroidal shell that is a first semiconductor (e.g., CdSe) sandwiched between a core and an outer layer that are a wider band gap semiconductor (e.g., CdS). The active emissive layer is formed by mixing a perovskite solution with a colloid to generate a blended mixture, where the colloid is the QSs suspended in a same solvent used for the perovskite solution. The perovskite solution is coated on a substrate to form a film that is then annealed, and electrodes are formed to flow a current through the active emissive layer, causing emitted light.

Abstract: Active emissive layers (e.g., of a light-emitting electrochemical cell (LEC)) are provided and can comprise zero-dimensional (0D) perovskite material in combination with a three-dimensional (3D) perovskite material, as well as electroluminescent devices (e.g., LECs) utilizing such active emissive layers and methods of fabricating and using such active emissive layers and electroluminescent devices. The 0D perovskite material can be incorporated into a matrix film of the 3D perovskite material. The 0D perovskite material can be, for example, perovskite nanocrystals (PNCs). The 0D perovskite material can be, for example, Cs4PbBr6, and the 3D perovskite material can be, for example, CsPbBr3.