Two-dimensional nanostructures may effectively be utilized as electrode materials for lithium/sodium-ion batteries to enhance the energy and power densities and cycling stability, and to satisfy the increasing demands of electrical vehicles and power stations. This review introduces the “geometry-driven” concept to illuminate the mechanisms related to various geometric sites in 2D materials for improving their electrochemical performance. The geometric sites of 2D materials are categorized into point-like, line-like, and plane-like defects. The electronic structures of geometric sites are then discussed. Hierarchical materials constructed from 2D materials, such as 3D crumpled nanoparticles, nanoflowers, and heterostructures, are highlighted. A summary of applications of the in situ transmission electron microscopy (TEM) technique is presented toward understanding the mechanisms of geometric-site effects in 2D materials. Finally, some perspectives on the geometry concept for material designs, theoretical calculations for performance prediction, and modern in situ TEM techniques for uncovering electrochemical mechanisms are discussed.

二维纳米结构可以有效地用作锂/钠离子电池的电极材料，以提高能量和功率密度以及循环稳定性，并满足电动汽车和发电站日益增长的需求。这篇综述引入了“几何驱动”的概念，以阐明与2D材料中各种几何部位有关的机制，以改善其电化学性能。2D材料的几何位置可分为点状，线状和平面状缺陷。然后讨论了几何位置的电子结构。突出显示了由2D材料构造的分层材料，例如3D皱缩的纳米颗粒，纳米花和异质结构。现场应用摘要提出了透射电子显微镜（TEM）技术，以了解2D材料中几何部位效应的机理。最后，讨论了有关材料设计的几何概念，用于性能预测的理论计算以及用于揭示电化学机理的现代原位TEM技术的一些观点。