The Interfacial Regulation Strategies of Perovskite Light-Emitting Diodes through Alkali Metal Compounds

Perovskite light-emitting diodes exhibit great potential in the fields of display and lighting, yet their performance is still limited by interfacial nonradiative recombination and charge imbalance. Although alkali metal compounds (AMCs) have been extensively studied as perovskite lattice components or bulk dopants, the strategy of using AMCs as functional interlayers or interfacial modifiers has received far less attention than it deserves. Despite the fact that this strategy has been proven effective, there is still a lack of systematic sorting and review of its multidimensional action mechanisms. We aim to fill this gap and explore the multiple interfacial roles of AMCs. This review not only provides a perspective for understanding the interfacial physicochemical processes related to AMCs, but also offers theoretical insights for the design and fabrication of high-performance and stable device.