A Ferroelectric Zinc-Based Complex with Ultraviolet Emission

Luminescent ferroelectrics have shown great application prospects in the fields of multifunctional sensors, anticounterfeiting and encryption technology, information storage, and optoelectronic devices due to the coexistence and coupling of fluorescence and spontaneous polarization. Although some ferroelectrics with luminescent properties have been developed in the organic-inorganic hybrid ferroelectrics (OIHFs) system and inorganic ferroelectrics in the past few years, the problems that cannot be avoided in further practical applications are impure components and internal defects, which will greatly weaken their performance and durability. Ferroelectric complexes are expected to open up new avenues for luminescent ferroelectrics due to their simple preparation, single component, and chemical diversity, but still remain unexplored. Here, we have realized the combination of ferroelectricity and photoluminescence in a metal complex [Zn(Dimebipy)Cl₂], which exhibits an mmmFmm2-type ferroelectric phase transition at about 346 K and efficient ultraviolet emission (346 nm) with a photoluminescence quantum yield of 32.4% at room temperature. Biosafe ligand and low-toxicity metal make it possible to apply in biomedical imaging and multichannel sensors. This discovery provides a new direction to explore ultraviolet emissive ferroelectrics for optoelectronic devices and biomedical applications.