High-entropy enabled two-dimensional ferroelectricity and memristive synapses in van der Waals layered materials

Two-dimensional ferroelectric materials offer opportunities for ultrathin non-volatile electronics, but their development is limited by stringent structural requirements for intrinsic polarity. Here we show that high-entropy engineering can induce switchable polarization in centrosymmetric van der Waals materials. By introducing configurational disorder into layered metal phosphorus trisulfides, we synthesize (MnFeCoNi)_1-xCd_xPS₃ single crystals exhibiting electric-field-induced polar states and ferroelectric-like switching at ±0.5 V, with a transition temperature up to 523 K. Combined calculations and characterizations reveal that polarization originates from electric-field-driven Cd²⁺ migration enabled by lattice distortions and heterogeneous coordination environments. This migration-mediated mechanism differs from conventional ferroelectric models and enables non-volatile neuromorphic functions, including long-term potentiation and bidirectional weight modulation. This work establishes high-entropy engineering as a strategy for manipulating ion migration dynamics in two-dimensional layered materials, opening a pathway toward emergent ferroelectric-like states beyond the conventional requirement of non-centrosymmetric structures.