Ferroelectric Domains and Domain Walls in Organic–Inorganic Hybrid Perovskites

Ferroelectric domains and domain walls (DWs) in organic–inorganic hybrid perovskites (OIHPs), particularly in 2D OIHPs, represent an intriguing platform for studying how unique microscopic properties can emerge at the domain level that are distinct from bulk properties. Ferroelectric domains and DWs feature domain-specific chiral photonics, charge separation pathways, nonlinear optical responses, and a domain-switchable spin texture. The relative orientations of differently polarized ferroelectric domains can break mirror symmetries and generate planar chirality, leading to metasurface-like responses toward light. The ability to reverse spin textures under an electric field offers dynamic control over spin states, making them highly suitable for spintronic applications. Recent advances in atomic-scale characterization have provided valuable insights into the atomic arrangements within ferroelectric domains and DWs that are different from ferroelastic domains in 2D OIHPs. The ability to produce a specific domain structure and control their polarization unlocks a materials platform where chirality, spin, charge, and light are dynamically coupled. This convergence could redefine optoelectronics, spintronics, and energy technologies, paving the way for a transformative future of adaptive multifunctional devices.