In Situ Construction of “Anchor‐Like” Structures in FeNCN for Long Cyclic Life in Sodium‐Ion Batteries
作者：Penghui Guo, Liyun Cao, Rong Wang, Yunfei Hu, Zhanwei Xu, Jianfeng Huang, Chunyan Yao, Ling Guo, Yayi Cheng, Jiayin Li, Koji Kajiyoshi · 发表于：Advanced Functional Materials · 年份：2020 · DOI：10.1002/adfm.202000208 · 被引用次数：40 · 研究领域：Advancements in Battery Materials、Inorganic Chemistry and Materials、MXene and MAX Phase Materials
Abstract Iron carbodiimide (FeNCN) is a high‐reactivity anode material for sodium‐ion batteries. However, strict synthesis technology and poor electrochemical stability limit its application. FeNCN polyhedrons are prepared using a facile one‐step pyrolysis process. In these polyhedrons, many “anchor‐like” structures are in situ constructed with FeC bonds. These FeC bonds connect the FeNCN polyhedrons closely. The FeNCN polyhedrons with “anchor‐like” structures exhibit good electrochemical stability, that is, high capacity retention of 79.9% (408 mAh g−1) at 0.5 A g−1 after 300 cycles. Further analysis suggests that the FeC bond plays an important role to improve the structural stability of FeNCN polyhedrons. The “anchor‐like” structures with FeC bonds can hold FeNCN polyhedrons closely when Na+ intercalates, avoiding structural breakage with obvious capacity loss. This work provides a novel synthesis technology of FeNCN and helps related researcher to deepen the understanding of this material, as well as provide inspirations as to improving the electrochemical stability of related materials.