Achieving High‐Performance 3D K<sup>+</sup>‐Pre‐intercalated Ti<sub>3</sub>C<sub>2</sub>T<sub><i>x</i></sub> MXene for Potassium‐Ion Hybrid Capacitors via Regulating Electrolyte Solvation Structure
Shuoqing Zhao, Zhichao Liu, Guanshun Xie, Xin Guo, Ziqi Guo, Fei Song, Guohao Li, Chi Chen, Xiuqiang Xie, Nan Zhang, Bing Sun, Shaojun Guo, Guoxiu Wang
Abstract
Abstract The development of high‐performance anode materials for potassium‐based energy storage devices with long‐term cyclability requires combined innovations from rational material design to electrolyte optimization. A three‐dimensional K + ‐pre‐intercalated Ti 3 C 2 T x MXene with enlarged interlayer distance was constructed for efficient electrochemical potassium‐ion storage. We found that the optimized solvation structure of the concentrated ether‐based electrolyte leads to the formation of a thin and inorganic‐rich solid electrolyte interphase (SEI) on the K + ‐pre‐intercalated Ti 3 C 2 T x electrode, which is beneficial for interfacial stability and reaction kinetics. As a proof of concept, 3D K + ‐Ti 3 C 2 T x //activated carbon (AC) potassium‐ion hybrid capacitors (PIHCs) were assembled, which exhibited promising electrochemical performances. These results highlight the significant roles of both rational structure design and electrolyte optimization for highly reactive MXene‐based anode materials in energy storage devices.