Solid-state batteries can ensure high energy density and safety in lithium metal batteries, while polymer electrolytes are plagued by slow ion kinetics and low selective transport of Li⁺. Metal-organic frameworks (MOFs) are proposed as emerging fillers for solid-state poly(ethylene oxide)(PEO) electrolytes, however, developing functionalized MOFs and understanding their roles on ion transfer has proven challenging. Herein, combining computational and experimental results, the functional group regulation in MOFs can effectively change surficial charge distribution and limit anion movement is revealed, providing a potential solution to these issues. Specifically, functionalized 2D MOF sheets are designed through molecular engineering to construct high-performance composite electrolytes, where the electron-donating effect of substituents in 2D-MOFs effectively limits the movement of ClO₄⁻ and promotes mechanical properties and ion migration numbers (0.36 up to 0.64) of PEO. As a result, Li/Li cells with composite electrolyte exhibit superior cyclability for 1000 h at a current density of 0.2 mA cm⁻². Meanwhile, the solid LiFePO₄/Li battery delivers highly reversible capacities of 148.8 mAh g⁻¹ after 200 cycles. These findings highlight a new approach for anion confinement through the use of functional group electronic effects, leading to enhanced ionic conductivity, and a feasible direction for high-performance solid-state batteries.

中文翻译：

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用于先进固体锂电池的具有快速锂离子传导功能的功能化二维金属有机框架纳米片

固态电池可以确保锂金属电池的高能量密度和安全性，而聚合物电解质则受到离子动力学慢和Li ⁺选择性传输低的困扰。金属有机框架（MOF）被提议作为固态聚环氧乙烷（PEO）电解质的新兴填料，然而，开发功能化MOF并了解其在离子转移中的作用已被证明具有挑战性。在此，结合计算和实验结果，揭示了MOF中的官能团调控可以有效改变表面电荷分布并限制阴离子运动，为这些问题提供了潜在的解决方案。具体来说，功能化2D MOF片通过分子工程设计来构建高性能复合电解质，其中2D-MOF中取代基的给电子效应有效地限制了ClO 4 - 的运动，并提高了机械性能和离子迁移数（_0.36^以上）至0.64)的PEO。结果，具有复合电解质的Li/Li电池在0.2 mA cm ^-2的电流密度下表现出优异的1000小时循环性能。同时，固体LiFePO _{4 /Li电池在200次循环后可提供148.8 mAh g} ^-1的高可逆容量。这些发现强调了一种通过使用官能团电子效应来限制阴离子的新方法，从而增强离子电导率，并为高性能固态电池提供了可行的方向。