High-Temperature Ferroelectricity and Photoluminescence in a Hybrid Organic–Inorganic Compound: (3-Pyrrolinium)MnCl3

Coupling of ferroelectricity and optical properties has become an interesting aspect of material research. The switchable spontaneous polarization in ferroelectrics provides an alternative way to manipulate the light–matter interaction. The recent observation of strong photoluminescence emission in ferroelectric hybrid organic–inorganic compounds, (pyrrolidinium)­MnX3 (X = Cl or Br), is an attractive approach to high efficiency luminescence with the advantages of ferroelectricity. However, (pyrrolidinium)­MnX3 only displays ferroelectricity near or below room temperature, which limits its future applications in optoelectronics and multifunctional devices. Here, we rationally designed and synthesized high-temperature luminescent ferroelectric materials. The new hybrid compound (3-pyrrolinium)­MnCl3 has a very high Curie temperature, T c = 376 K, large spontaneous electronic polarization of 6.2 μC/cm2, and high fatigue resistance, as well as high emission efficiency of 28%. This finding is a further step to the practical use of ferroelectric luminescence based on organic–inorganic compounds.