分级结构二维复合材料的构筑及其在能源转换与存储中的应用

Construction of Hierarchically Structured Two-Dimensional Composites and Their Applications in Energy Conversion and Storage

二维材料因其具有巨大的比表面积、丰富的活性位点及较短的离子扩散途径,被认为是最具潜力的电化学活性材料之一,受到研究者的广泛关注。然而,由于高表面能和大层间范德华力的作用,二维材料易发生堆叠,从而导致性能下降,严重影响其进一步应用。在保留二维材料物化特性的基础上,构筑分级结构二维复合材料是解决二维材料堆叠问题的最有效的方法之一。分级结构二维复合材料不仅保留复合材料中各组分的本征特性,而且能够发挥各组分之间的协同作用,增大比表面积,暴露更多活性位点,赋予复合材料优异的性能。总结了近年来分级结构二维复合材料的研究进展,分别介绍了液相模板法、化学气相沉积法和非模板法3种可控制备方法,重点讨论了分级结构二维复合材料在电化学储能与转化领域的应用,在此基础上,分析了该研究领域当前仍存在的问题,并对其未来的发展方向做出了展望。

Due to the large specific surface area,abundant active sites and short ion diffusion pathway,two-dimensional( 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 template-free 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.