Abstract
Two-dimensional (2D) ferroelectric semiconductors, as an emerging class of functional materials, attract considerable interest in nanoelectronics, spintronics, and optoelectronics, owing to their unique ability to combine ferroelectricity and semiconducting properties at the ultimate thickness limit. This review provides a comprehensive overview of the development, fundamental mechanisms, and recent advances of 2D ferroelectric semiconductors. The origins and unique characteristics of 2D ferroelectricity are discussed, and representative intrinsic 2D ferroelectric semiconductors as well as extrinsic systems are summarized. The potential applications of these materials in electronics, optoelectronics, spintronics, and valleytronics are discussed in detail. Finally, the key challenges facing the field are outlined, and perspectives on future directions are offered. This review aims to provide a systematic reference for both fundamental studies and technological development, fostering the advancement of 2D ferroelectric semiconductors toward high-performance and multifunctional device applications.