A multifunctional molecular ferroelectric with chiral features, a high Curie temperature, large spontaneous polarization and photoluminescence: (C9H14N)2CdBr4

• Published in: Chemical science (Cambridge) Vol. 12; no. 39; pp. 13061 - 13067
• Main Authors: Yu-Kong, Li, Yuan-Yuan, Lai, Ting-Ting, Ying, Ding-Chong, Han, Yu-Hui, Tan, Yun-Zhi Tang, Peng-kang, Du, Zhang, Hao
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 21.10.2021; The Royal Society of Chemistry
• Subjects: Anomalies; Broadband; Chemistry; Chiral materials; Curie temperature; Ferroelectric domains; Ferroelectric materials; Ferroelectricity; Ferroelectrics; Metal halides; Optoelectronic devices; Photoluminescence; Polarization; Room temperature; Tetrahedra
• ISSN: 2041-6520; 2041-6539
• DOI: 10.1039/d1sc03964d

Low-dimensional chiral organic–inorganic hybrid metal halides have attracted a lot of attention in recent years due to their unique intrinsic properties, including having potential applications in optoelectronic and spintronic devices. However, low-dimensional chiral molecular ferroelectrics are very rare. In this paper, we report a novel zero-dimensional molecular ferroelectric (C9H14N)2CdBr4 (C9H14N+ = protonated 3-phenylpropylamine), which has obvious dielectric and thermal anomalies and shows a high Curie temperature at 395 K. It crystallizes in the P21 space group at room temperature, showing a strong CD signal, large spontaneous polarization (Ps = 13.5 μC cm−2), and a clear ferroelectric domain. In addition, it also exhibits a flexible SHG response. The photoluminescence spectrum shows that 1 has broadband luminescence. At the same time, compound 1 has a wide band gap, which is mainly contributed to by the inorganic CdBr4 tetrahedron. The high tunability of low-dimensional chiral molecular ferroelectrics also opens up a way to explore multifunctional chiral materials.