米粒型氯插层NiFe层状双金属氢氧化物作为新概念氯离子电池正极材料  

Chloride Inserted Grain-like NiFe Layered Double Hydroxide Cathode for the New Concept of Chloride Ion Battery

作　　者：尹青 杨姝涵 宋挚豪 赵泽羽 李泳志 赵丹阳 戚继球[1] 隋艳伟[1] YIN Qing;YANG Shuhan;SONG Zhihao;ZHAO Zeyu;LI Yongzhi;ZHAO Danyang;QI Jiqiu;SUI Yanwei(School of Materials and Physics,China Universiy of Mining and Technology,Xuzhou 221116,Jiangsu,China)

机构地区：[1]中国矿业大学材料与物理学院,江苏徐州221116

出　　处：《材料导报》2023年第21期9-16,共8页Materials Reports

基　　金：中央高校基本科研业务费专项资金(2022QN1090)。

摘　　要：以卤素氯离子为载荷离子的新概念氯离子电池(CIBs)被认为是“下一代”大规模、高安全电化学储能设备的有力竞争者。层状双金属氢氧化物(LDHs)因具有高的储氯容量与稳定的层状拓扑结构,被视为一类极具发展前景的CIBs正极材料。本工作以MOFs材料MIL-88A为模板前驱体,采用先水解后离子交换的两步法,制备了具有米粒形貌的氯离子插层NiFe LDH纳米多面体(g-NiFe-Cl LDH),其具有高于常规NiFe LDH纳米片两倍的比表面积。这种纳米多面体g-NiFe-Cl LDH材料能够克服一般LDHs纳米片层板间易堆积的本征缺陷,增大材料电化学活性位点暴露率,提高其与电解液的有效接触面积,促进氯离子扩散动力学,最终实现其储氯性能的强化。将g-NiFe-Cl LDH作为CIB正极材料时,电池表现出286.1 mAh/g的最大放电比容量,且在经过200次充放电循环后仍可保持155.3 mAh/g的稳定放电比容量,为常规NiFe-Cl LDH纳米片的两倍。同时,g-NiFe-Cl LDH基CIB的储能机理也被揭示:充电过程中,g-NiFe-Cl LDH正极中的氯离子从层间脱出,其主体层板中的双金属Ni^(3+)/Fe^(3+)被还原成Ni^(2+)/Fe^(2+)。考虑到LDHs材料简单的制备过程和高度可调的化学组分,本工作为设计具有高容量输出和长循环寿命的CIBs正极材料提供了新的思路。The new type of anion shuttle battery representing by thechloride-ion battery(CIB),is considered to be one of the competitor for the‘next generation’large-scale electrochemical energy storage system,owing to their significant safety advantages and low cost.However,it is still a great challenge to exploit high performance cathode materials for the practical application of CIBs.Layered double hydroxides(LDHs)have been considered as highly potential cathodes for CIBs because of their tunable interlayer spacing and unique topological transformation characte-ristic.Herein,the chloride inserted grain-like NiFe LDH(g-NiFe-Cl LDH)with large specific surface area is prepared using the MIL-88A as precursor through the hydrolysis process followed by anion exchange methode.The g-NiFe-Cl LDH could not only overcome the inherent defects of laminated stack by LDHs nanosheets,but also increase the exposure rate of electrochemical active sites,which accordingly improves the effective contact between electrode and electrolyte and promotes the chloride ion diffusion kinetics.The g-NiFe-Cl LDH is then used as cathode for CIB,which delivers a maximum discharge specific capacity of 286.1 mAh/g and a stable capacity of 155.3 mAh/g over 200 cycles.The Cl-storage mechanism of g-NiFe-Cl LDH cathode is also revealed that the reversible intercalation/deintercalation of chloride ions in LDH gallery along with the oxidation state changes in Ni 2+/Ni 3+and Fe 2+/Fe 3+oxidation couples.This work proviedes some new insights for the design and performance enhancement for the new LDHs-based anionic energy storage system.

关 键 词：氯离子电池 层状双金属氢氧化物(LDHs) 金属有机框架(MOF) 阴离子电化学储能 可逆氯离子嵌入/脱出机制 

分 类 号：O646[理学—物理化学]