Progress in Flexoelectric Effect Research and Related Applications

ABSTRACT The flexoelectric effect refers to the electromechanical coupling between electric polarization and mechanical strain gradient. It universally exists in a variety of materials in any space group, such as liquid crystals, dielectrics, biological materials, and semiconductors. Because of its unique size effect, nanoscale flexoelectricity has shown novel phenomena and promising applications in electronics, optronics, mechatronics, and photovoltaics. In this review, we provide a succinct report on the discovery and development of the flexoelectric effect, focusing on flexoelectric materials and related applications. Finally, we discuss recent flexoelectric research progress and still‐unsolved problems.