A Coral‐Like FeP@NC Anode with Increasing Cycle Capacity for Sodium‐Ion and Lithium‐Ion Batteries Induced by Particle Refinement
Canpei Wang, Jitong Yan, Tianyu Li, Zhiqiang Lv, Xin Hou, Yongfu Tang, Huamin Zhang, Qiong Zheng, Xianfeng Li
Abstract
Abstract We present a coral‐like FeP composite with FeP nanoparticles anchored and dispersed on a nitrogen‐doped 3D carbon framework (FeP@NC). Due to the highly continuous N‐doped carbon framework and a spring‐buffering graphitized carbon layer around the FeP nanoparticle, a sodium‐ion battery with the FeP@NC composite exhibits an ultra‐stable cycling performance at 10 A g −1 with a capacity retention of 82.0 % in 10 000 cycles. Also, particle refinement leads to a capacity increase during cycling. The FeP nanoparticles go through a refining–recombination process during the first cycle and present a global refining trend after dozens of cycles, which results in a gradually increase in graphitization degree and interface magnetization, and further provides more active sites for Na + storage and contributes to a rising capacity with cycling. The capacity ascending phenomenon can also extend to lithium‐ion batteries.