Boosting Fast and Stable Potassium-ion Storage by Synergistic Interlayer and Pore-structure Engineering

Carbon-based material has been regarded as one of the most promising electrode materials for Potassium-ion batteries (PIBs). However, the battery performance based on reported porous carbon electrodes is still unsatisfactory, while the in-depth K-ion storage mechanism remains relatively ambiguous. Herein, we propose a facile “in situ template bubbling” method for synthesizing interlayer tuned hierarchically porous carbon with different metallic ions, which delivers superior K-ion storage performance, especially the rate capability (158.6 mAh g^-1@10.0 A g^-1) and high-rate cycling stability (82.8% capacity retention after 2000 cycles at 5.0 A g^-1). The origin of the excellent rate performance is revealed by the deliberately designed consecutive CV measurements, Ex situ Raman tests, GITT and theoretical simulations. Considering the facile preparation strategy, superior electrochemical performance and insightful mechanism investigations, this work can provide fundamental understandings for high performance PIBs and related energy storage devices like sodium-ion batteries, aluminum-ion batteries, electrochemical capacitors and dual-ion batteries.