High K-storage performance based on the synergy of dipotassium terephthalate and ether-based electrolytes
High K-storage performance based on the synergy of dipotassium terephthalate and ether-based electrolytes
复制标题
基于对苯二甲酸二钾和醚基电解质协同作用的高储钾性能
DOI：
10.1039/c6ee03185d
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发表时间：
2017-02-01
影响因子：
32.5
通讯作者：
Chen, Jun
中科院分区：
文献类型：
--
作者：
Lei, Kaixiang;Li, Fujun;Chen, Jun
钾离子电池（KIB）的发展强烈依赖于具有高安全性和良好电化学性能的阳极。在这里，我们首次实现了基于对苯二甲酸二钾（K2 TP）和基于1，2-二甲氧基乙烷（DME）的电解质的协同作用的KIB的优异阳极性能。K2 TP具有典型的层状结构和K+转运通道。它在200 mA g（-1）下具有249 mA h g（-1）的大容量，在1000 mA g（-1）下充放电500次后，容量保持率高达94.6%，库仑效率为100%。这归因于K2 TP的活性羧酸基团和柔性分子结构，以及在DME基电解质中形成的稳定的固体电解质界面（SEI）。此外，K2 TP的氧化还原电压约为0.6 V，有利于K+的插入，而不是在放电过程中的沉积。这使得K2 TP成为一种很有前途的KIBs阳极材料，并对KIBs的新体系进行了更多的研究。
Potassium-ion batteries (KIBs) are strongly dependent on the development of anodes with high safety and good electrochemical performance. Here, we achieved excellent anode performance of KIBs based on the synergy of dipotassium terephthalate (K2TP) and a 1,2-dimethoxyethane (DME)-based electrolyte for the first time. The K2TP is featured as a typical layered structure with K+ transport channels. It delivers a large capacity of 249mA h g (-1) at 200mA g (-1) and a high capacity retention of 94.6% after 500 cycles of discharge and charge at 1000 mA g (-1) with a Coulombic efficiency of 100%. This is attributed to the active carboxylate groups and the flexible molecular structure of K2TP, and the stable solid electrolyte interphase (SEI) formed in the DME-based electrolyte. Furthermore, the redox voltage around 0.6 V of K2TP favors K+ insertion rather than deposition during discharge. These make K2TP a promising anodematerial for KIBs, and encouragemore investigations into the new system of KIBs.