Core–Shell Three-Dimensional Perovskite Nanocrystals with Chiral-Induced Spin Selectivity for Room-Temperature Spin Light-Emitting Diodes

We developed type-II core–shell nanocrystals (NCs) with a chiral low-dimensional perovskite shell and an achiral 3D MAPbBr₃ core. The core–shell NCs exhibit spin-polarized luminescence at the first excitation band of the achiral core, which is due to the chiral-induced spin selectivity (CISS) effect-governed spin-dependent shell-to-core electron transportation and the subsequent electron–hole recombination in the core. The preferred spin state of the transferred electrons is determined by the handness of the chiral shell. For the core–shell NCs film, a photoluminescence quantum yield (PLQY) of 54% and a circularly polarized luminescence (CPL) with a maximum |g_lum| of 4.0 × 10^–3 are obtained at room temperature. Finally, we achieved a spin-polarized light-emitting diode (spin-LED), affording a circularly polarized electroluminescence (CP-EL) with a |g_CP‑EL|of 6.0 × 10^–3 under ambient conditions.