Willow‐Leaf‐Like ZnSe@N‐Doped Carbon Nanoarchitecture as a Stable and High‐Performance Anode Material for Sodium‐Ion and Potassium‐Ion Batteries
Caifu Dong, Leqiang Wu, Yanyan He, Yanli Zhou, Xiuping Sun, Wei Du, Xueqin Sun, Liqiang Xu, Fuyi Jiang
Abstract
Abstract ZnSe is regarded as a promising anode material for energy storage due to its high theoretical capacity and environment friendliness. Nevertheless, it is still a significant challenge to obtain superior electrode materials with stable performance owing to the serious volume change and aggregation upon cycling. Herein, a willow‐leaf‐like nitrogen‐doped carbon‐coated ZnSe (ZnSe@NC) composite synthesized through facile solvothermal and subsequent selenization process is beneficial to expose more active sites and facilitate the fast electron/ion transmission. These merits significantly enhance the electrochemical performances of ZnSe@NC for sodium‐ion batteries (SIBs) and potassium‐ion batteries (PIBs). The obtained ZnSe@NC exhibits outstanding rate performance (440.3 mAh g −1 at 0.1 A g −1 and 144.4 mAh g −1 at 10 A g −1 ) and ultralong cycle stability (242.2 mAh g −1 at 8.0 A g −1 even after 3200 cycles) for SIBs. It is noted that 106.5 mAh g −1 can be retained after 550 cycles and 71.4 mAh g −1 is still remained after 1500 cycles at 200 mA g −1 when applied as anode for PIBs, indicating good cycle stability of the electrode. The possible electrochemical mechanism and the ionic diffusion kinetics of the ZnSe@NC are investigated using ex situ X‐ray diffraction, high‐resolution transmission electron microscopy, and a series of electrochemical analyses.