Chlorine Substituted Organic Linker in Two-Dimensional Halide Double Perovskite Ferroelectric with Directional Dependence Properties

Ferroelectric materials have garnered significant interest due to their unique electrical and structural properties, holding immense promise for diverse electronic applications. This study introduces a novel 2D layered halide double perovskite ferroelectric material denoted as Cl_1.14Br_2.86PA₄AgInBr₈ (CPAIn). Through the strategic substitution of halogenated A-site organic linker 3-chloropropylammonium, CPAIn demonstrates exceptional non-centrosymmetric properties and remarkable ferroelectric behaviour, with a Curie temperature (Tc) of 197°C. One of the key findings of this research is CPAIn's anisotropic ferroelectric behaviour, characterized by a notably high spontaneous polarization (Ps) of 6.25 µC.cm^-2 along the perpendicular orientation to the octahedral layers. This observation underscores its potential for applications requiring precise control over polarization direction. Notably, the material exhibits differential resistivity along distinct crystallographic axes, with resistance measuring 9.71 MΩ.cm along the parallel direction and 18.81 MΩ.cm along the perpendicular direction. This variance is attributed to the role of organic cations as insulators, modulating charge transfer dynamics within the material. As demonstrated by CPAIn, the ferroelectric characteristics present intriguing opportunities for future development and construction of advanced electronic devices. This endeavour represents a noteworthy advancement in tapping into the complete capabilities of ferroelectric materials for a diverse array of technological uses. The distinctive qualities of CPAIn outlined in this investigation render it an attractive contender for further research and pragmatic integration into cutting-edge electronic devices.