Green Doping and Dual‐Mode Confinement in SnS<sub>2</sub>‒P‒SPAN Anodes: Unveiling High‐Performance Sodium/Potassium Ion Full‐Cells Across the Wide Temperature Ranges
Yiyi Wang, Wenbin Lai, Fuyu Xiao, Mingyang Ge, Fenqiang Luo, Xiang Hu, Renpin Liu, Peixun Xiong, Qinghua Chen, Qingrong Qian, Zhenhai Wen, Lingxing Zeng
Abstract
ABSTRACT Tin sulfide (SnS 2 ) is a promising anode material for sodium/potassium‐ion batteries (SIBs/PIBs) due to its large interlayer spacing and high theoretical capacity. However, its application is hindered by sluggish kinetics, volume expansion, and low conductivity. In this work, a synergistic engineering route is proposed that combining environmentally friendly chlorella with sulfurized polyacrylonitrile (SPAN) to achieve green doping and dual‐mode confinement SnS 2 ‐based anode. The SPAN matrix prevents SnS 2 agglomeration, enhances charge transfer, and improves structural stability, while phosphorus (P) doping accelerates “solid‒solid” conversion kinetics. The SnS 2 ‒P‒SPAN anode demonstrates outstanding sodium/potassium storage performance across a wide temperature range (‒40°C to 70°C), delivering high reversible capacities, excellent rate capability, and exceptional long‐term cycling stability. The reliability of the as‐developed strategy in a SnS 2 ‒P‒SPAN//NaNi 0.4 Fe 0.2 Mn 0.4 O 2 full cell is also verified, which shows strong practical potential with high capacity and long durability (241 mAh g −1 /800 cycles/0.5 A g −1 /25°C; 159 mAh g −1 /400 cycles/0.5 A g −1 /60°C; 105 mAh g −1 /800 cycles/0.5 A g −1 /‒15°C). The associated electrochemical mechanisms of SnS 2 ‒P‒SPAN are elucidated through comprehensive electrochemical tests, in/ex situ analyses. The theoretical calculation unveil that P‐doping helps to enhance the adsorption capacity of the Na + and discharge products. This work may pave the way for developing promising yet imperfect electrode materials in the field of energy storage.