Recent progress on two-dimensional ferroelectrics: Material systems and device applications

Ferroelectrics are a type of material with a polar structure and their polarization direction can be inverted reversibly by applying an electric field. They have attracted tremendous attention for their extensive applications in non-volatile memory, sensors and neuromorphic computing. However, conventional ferroelectric materials face insulating and interfacial issues in the commercialization process. In contrast, two-dimensional (2D) ferroelectric materials usually have excellent semiconductor performance, clean van der Waals interfaces and robust ferroelectric order in atom-thick layers, and hold greater promise for constructing multifunctional ferroelectric optoelectronic devices and nondestructive ultra-high-density memory. Recently, 2D ferroelectrics have obtained impressive breakthroughs, showing overwhelming superiority. Herein, firstly, the progress of experimental research on 2D ferroelectric materials is reviewed. Then, the preparation of 2D ferroelectric devices and their applications are discussed. Finally, the future development trend of 2D ferroelectrics is looked at.