| 초록 |
All-inorganic CsPbI3 perovskite has recieved much attention for replacting organic-inorganic hybrid perovskite due to its excellent humidity and thermal stability. However, formation of non-perovskite yellow δ-phase at room temperature hindered its application in optoelectronic devices. We present that a small quantity of poly(ethylene oxide) (PEO) added to the precursor solution effectively inhibits the formation of the yellow δ-phase during film preparation, and promotes the development of a black α-phase at a low crystallization temperature. A thin, dense, pinhole-free α-phase CsPbI3 film with excellent photoluminescence is successfully employed in a light-emitting diode, yielding the characteristic red emission of the perovskite film at 695 nm with brightness, external quantum efficiency, and emission band width of approximately 101 cd m−2, 1.12%, and 32 nm, respectively. |
