(1. College of Materials and Engineering, ZheJiang University of Technology, Hangzhou 310014, China) (2. Center for Membrane Separation and Water Science and Technology, Ocean College, Zhejiang University of Technology, Hangzhou 310014, China)
Due to the large specific surface area, abundant active sites and short ion diffusion pathway, twodimensional(2D) materials are considered to be one of the most promising electrochemically active materials, and thus received extensive attention of the researchers. However, 2D materials are prone to stacking because of their high surface energy and large interlayer van der Waals forces, which leads to performance degradation and seriously affects their further applications. In order to solve the problem of 2D materials stacking and retain the physical and chemical properties of the original 2D materials, the construction of hierarchical structure 2D composite materials have become one of the most effective means. The construction of hierarchical structure not only preserves intrinsic characteristics of each component in the composites, but also achieves significantly increased specific surface area, exposes more active sites on the 2D material interface, and improves the comprehensive properties of the composites by virtue of the synergistic effect between the components. In this review, the recent progress in hierarchically structured 2D composites was summarized, beginning with the introduction of the typical three preparation methods: liquid phase template method, chemical vapor deposition method and templatefree method. Moreover, the applications of hierarchically structured 2D composites in the field of electrochemical energy storage and transformation were emphatically discussed. The existing challenges of 2D composite materials with hierarchically structures were further discussed and the future research direction has prospected.