Edge engineering in chemically active two-dimensional materials

When "cut off" continuous and uniform basal plane of two-dimensional (2D) materials, edges appear at cross-sections. Such edges with unique one-dimensional (1D) structures and bound-states significantly alter materials' local chemical activities and have been extensively investigated as model platforms for investigating structure-property-performance relationships for chemistry. Many interesting phenomena have been discovered in the past decades, highlighting the importance of interactions between active species and edge atoms at the atomic level and making 1D edges as emerging catalysts with high efficiency, promising candidates for battery and electrochemical contacts. Here, this review focuses on the recent progress of edge synthesis and structural engineering methods, understanding of edge structure-activity mechanisms, and potential applications using edge sites. Challenges and prospects are also envisioned.