Defect Engineering of 2D Materials for Electrochemical Energy Storage

Abstract With the increasing demands for current clean energy technologies, researchers are paying more and more attention to the full utilization of energy storage devices. However, the development of energy storage technologies is still limited by different technical challenges that need to be well addressed. Owing to the high specific surface area, ultrahigh carrier mobility and excellent mechanical flexibility, 2D materials have shown prominent superiorities for a wide range of energy storage applications. For 2D materials, a series of intrinsic deficiencies such as comparatively low conductivity, sparse electroactive sites, and poor reversibility have been found to restrict their further applications in real devices. In particular, 2D materials could be further defectively engineered to achieve a meaningful breakthrough in further improving the power performance and cycle life that satisfies the industrial demands. For a comprehensive clarify of the defect effects, this review summarizes the controllable strategies to generate defects in 2D materials, along with various characterizations and applications to identify the mechanisms of defects on the improvement of electrochemical performance. Finally, future directions of defects engineering design and application prospects of defective 2D materials are provided.