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

Abstract

<p>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 “<i>in situ</i> 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<sup>-1</sup>@10.0 A g<sup>-1</sup>) and high-rate cycling stability (82.8% capacity retention after 2000 cycles at 5.0 A g<sup>-1</sup>). The origin of the excellent rate performance is revealed by the deliberately designed consecutive CV measurements, <i>Ex situ</i> 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.</p>

Expanding the ReS2 Interlayer Promises High-Performance Potassium-Ion Storage

“…Various kinds of strategies, such as nanostructure design to improve the kinetic property, combined with carbon-based materials to improve the electron conductivity, have already been utilized in ReS 2 -based electrodes to enhance the battery performance. ,, Nevertheless, due to the poor utilization of the interlayer distance and the weak van der Waals’ force, the presented ReS 2 -based electrodes still do not satisfy the requirements of high-rate electrochemical systems. Recently, the interlayer expanding strategy has been employed to improve WS 2 - and MoS 2 -based anodes in PIBs, demonstrating the enhanced kinetics of K + and electrons. − Inspired by the interlayer expanding strategy of MoS 2 and WS 2 in potassium-ion battery systems, herein, interlayer-expanded ReS 2 nanosheets were prepared through the hydrothermal process. The prepared nanocomposites show distinctive properties, which can significantly achieve higher K-ion transport kinetics. , Benefiting from the expanded interlayer distance, the synthesized composite shows excellent rate capability (EI-ReS 2 @rGO nanocomposite shows specific capacities of 432.5, 316.5, and 241 mAh g –1 under 0.05, 0.2, and 1.0 A g –1 current densities) and superior cycling stability (EI-ReS 2 @rGO nanocomposites keep 82.6% at 200 cycle), providing valid ionic kinetic diffusions for improving the electrochemical performance.…”