Boosting the Sodium Storage Performance of O3-Type Layered Oxide Cathode by Dual-Site Doping
Shuo Shi, Qian Yang, Simi Sui, Shuang Li, Yingxin Zhang, Zhuo Chen, Yuling Wu, Mingming Fan, Tongtong Huo, Xuejie Bai, Mingyue Li, G. Yu, Wen Zhang, Xunzhu Zhou, Lin Li, Kaixiang Lei, Shijian Zheng
Abstract
O3-type layered oxide materials with inherently sufficient Na content have attracted significant attention for sodium-ion batteries (SIBs). However, they suffer from unsatisfactory electrochemical reaction kinetics, irreversible phase transition, and structural degradation during the electrochemical cycling, resulting in poor sodium storage performance. Herein, we propose a Ca/Sn dual-site doping strategy to boost the electrochemical performance of the O3-type layered oxide cathode materials. The synergistic effect of Ca/Sn dual-site doping can modulate the coordination environment and chemical bonds of transition metal (TM) ions, leading to the fast charge transfer kinetics and highly reversible phase transition with a small volume change. The improved structural stability effectively suppresses TM dissolution and maintains particle integrity during long-term cycling. Therefore, Na 0.98 Ca 0.01 Ni 0.33 Fe 0.33 Mn 0.315 Sn 0.015 O 2 delivers superior cycling stability and excellent rate performance. This work highlights the critical role of dual-site doping in enhancing sodium storage performance and provides significant guidance for the design of high-performance cathode materials.