Thermo-responsive light-emitting metal complexes and related materials

Abstract

Thermo-responsive light-emitting materials have wide potential applications in temperature sensing, bioimaging, optoelectronic devices and information security, due to their intriguing luminescence property changes in response to temperature. Among them, light-emitting metal complexes and related coordination materials are appealing in possessing enormous structural diversity and excellent luminescence properties. The general thermo-responsive types and the underlying mechanism of these materials and recent progress in the development of thermo-responsive metal complexes and related materials are surveyed in this critical review, including small molecular metal complexes with different electronic configurations (d⁶, d⁸, d¹⁰, among others), metal clusters, coordination polymers, metal–organic frameworks (MOFs), and multicomponent coordination polymers and assemblies. A particular focus is given on how to build systems showing ratiometric lumunescence changes in response to temperature, including molecular dyads containing two chromophores, heterodimetallic clusters, mixed-metal MOFs, and energy donor–acceptor assemblies. In addition, the applications of these materials in temperature sensing, bioimaging, and information security are briefly discussed. A perspective is given in the Conclusion section to reflect potential guidelines for future research in this field.