锂硒电池ZIF-L衍生氮掺杂碳纳米片/碳布自支撑电极的电化学性能研究  

ZIF-L Derived Nitrogen-doped Carbon Nanosheets/Carbon Cloth Self-supported Electrode for Lithium-selenium Battery

作　　者：荀道祥 罗序维 周明冉 何佳乐 冉茂进 胡执一 李昱[1] XUN Daoxiang;LUO Xuwei;ZHOU Mingran;HE Jiale;RAN Maojin;HU Zhiyi;LI Yu(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China;Nanostructure Research Centre(NRC),Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学材料复合新技术国家重点实验室,武汉430070 [2]武汉理工大学纳微结构研究中心,武汉430070

出　　处：《无机材料学报》2024年第9期1013-1021,共9页Journal of Inorganic Materials

基　　金：国家自然科学基金(U22B6011,22275142,52103285);111引智计划(B20002);湖北省自然科学基金(2020CFB416)。

摘　　要：硒(Se)因其较高的体积比容量(3253 mAh cm^(-3))和电子电导率(1×10^(-5)S m^(-1))而成为新一代锂硒(Li-Se)电池储能材料。针对其反应过程中体积膨胀较大、容量衰减较快以及活性物质利用率低等问题,本研究通过在碳布(CC)上生长二维Zn基金属有机框架(ZIF-L)并碳化,设计了一种ZIF-L衍生氮掺杂碳纳米片/硒自支撑复合材料(Se@NC/CC)用于锂硒电池研究。ZIF-L碳化形成的氮掺杂碳纳米片中丰富的微孔结构有效缓解了反应过程中的体积膨胀,掺杂N原子有利于吸附反应过程中的Li2Se,减少活性物质损失。特别地,Se@NC/CC电极中Se和C之间存在强的化学键作用,在一定程度上也可以减少活性物质损失,提高整体性能稳定性。电化学测试表明,在0.5C(1.0C=675 mAh g^(-1))电流密度下,Se@NC/CC电极的初始放电比容量为574 mAh g^(-1),展现出高初始放电比容量;电流密度为2.0C时,初始放电比容量为453.3 mAh g^(-1),循环500圈后仍然具有406.2 mAh g^(-1)的容量;同时也表现出了良好的倍率性能,与文献报道相比有较明显的优势。本研究设计的柔性自支撑硒电极为先进碱金属-硒电池的硒宿主材料设计提供了新的研究思路。Selenium(Se)is considered as a new generation energy storage material of lithium-selenium(Li-Se)battery due to its high volume specific capacity(3253 mAh cm^(-3))and high electronic conductivity(1×10^(-5)S m^(-1)).To address the problems of volume expansion,fast capacity decay,and low utilization of active materials during its charging-discharging process,a ZIF-L derived nitrogen-doped nanosheets/selenium(Se@NC/CC)flexible self-supported composite electrode is designed in this study for lithium-selenium battery by growing two-dimensional zinc-based metallic organic framework(ZIF-L)on carbon cloth(CC).The rich microporous structure in the nitrogen-doped carbon nanosheets can effectively alleviate the volume expansion during the reaction process,and the doping of heteroatoms N helps to adsorb Li2Se and reduce the loss of active substances.In particular,it is found that there is strong chemical bonding between Se and C in the Se@NC/CC electrode,which also helps to reduce the loss of active materials and improve the performance.Electrochemical results show that the initial discharge specific capacity of the Se@NC/CC electrode is 574 mAh g^(-1)at a current density of 0.5C(1.0C=675 mAh g^(-1)),demonstrating a high initial discharge specific capacity.At a current density of 2.0C,the initial discharge specific capacity is 453.3 mAh g^(-1),which maintains at 406.2 mAh g^(-1)after cycling for 500 cycles and it also displays excellent rate performance compared to literature.Such a flexible self-supported selenium cathode designed in this study provides a new research route on the design of selenium host materials for advanced alkali metal-selenium batteries.

关 键 词：锂硒电池 碳布 自支撑 ZIF-L材料 碳纳米片 

分 类 号：TQ174[化学工程—陶瓷工业]