Recent Progress in the Stability of Red-Emissive Perovskite Nanocrystals for Light-Emitting Diodes

All-inorganic perovskite nanocrystals (PNCs) have been anticipated to be used in efficient and stable perovskite optoelectronic devices because of their suitable bandgap, broad absorption spectrum, and high color purity. However, long-term stability remains a major obstacle for the commercial application of PNCs. In particular, for red-emissive perovskites, the reaction to the environment is more sensitive than that for the green counterpart, which makes a phase transformation easily occur at room temperature. On the basis of CsPbI3 PNCs, we analyze the main instability factors of red-emissive PNCs (620–720 nm), including their structures, optoelectronic properties, and instability mechanism. We then summarize some strategies to improve the stability and performance of the perovskites and light-emitting diodes (LEDs). Furthermore, we discuss the challenge of scaling up the production of PNCs. Finally, we propose possible perspectives for the development of perovskite materials.