Regulation and application of organic luminescence from low-dimensional organic-inorganic hybrid metal halides

Organic solid-state luminescence shows broad application prospects in fields such as sensing, luminescent devices, information storage, and biological imaging. However, most organic molecules show poor luminescence performance in aggregated states. Efficient solid-state luminescence can be achieved by hybridization of organic luminescent groups and inorganic matrices at the molecular level. Among numerous organic/inorganic hybrid materials, the low-dimensional metal halides (LDMHs) developed in recent years have attracted widespread attention for their advantages of facile synthesis, good processability, and outstanding optical properties. Introducing suitable organic luminophores into inorganic metal halide frameworks can not only achieve a high quantum yield up to 100%, but also realize long-lived room temperature phosphorescence with a lifetime up to 1.2 s. It is of great significance to have a deep understanding of the luminescence mechanism and regulatory strategies of organic luminophores in LDMHs for achieving efficient and multicolor luminescence. In this review, the mechanism of organic luminescence in LDMHs is introduced based on different exciton behaviors. The regulatory strategies adopted to improve the luminescent performances of organic components in LDMHs are discussed in detail including bandgap engineering, energy transfer, molecular engineering, organic guest doping and external heavy atom effects. Finally, the potential applications and research prospects regarding LDMHs with organic luminescence are summarized for the future development of this area. In this review, the organic luminescence properties of low-dimensional organic-inorganic hybrid metal halides (LDMHs) are summarized, with emphasis on the mechanism, regulating strategy and applications of organic luminescence in LDMHs.