锂钠合金的原位电化学制备及“锂+钠”共储特性  

In-situ Electrochemical Preparation of Li-Na Alloy and the Co-storage of Li+and Na+Ions

作　　者：吴利军 郭守杰 张超 李知声 李唯聪 杨长春[2] WU Li-Jun;GUO Shou-Jie;ZHANG Chao;LI Zhi-Sheng;LI Wei-Cong;YANG Chang-Chun(College of Materials and Chemical Engineering,Xuchang University,Xuchang 461000,China;College of Chemistry,Zhengzhou University,Zhengzhou 450000,China)

机构地区：[1]许昌学院化工与材料学院,许昌461000 [2]郑州大学化学学院,郑州450000

出　　处：《应用化学》2022年第11期1757-1765,共9页Chinese Journal of Applied Chemistry

基　　金：河南省青年自然科学基金(No.202300410349);许昌学院创新团队项目(No.2022CXTD007);许昌学院校级科研项目(No.2021YB001)资助。

摘　　要：锂钠合金相较于单一锂或者单一钠具有更优异的性能,以钠金属为正极、锂金属为负极,以LiPF_(6)、NaClO_(4)以及锂钠混合离子电解液作为电解液,组装成纽扣电池,在梯度电流密度下进行充放电,成功实现了锂钠合金的原位电化学制备。得益于锂、钠双电化学活性离子的协同效应,不同钠含量的锂钠合金为负极的锂钠混合离子电容器均呈现良好的电化学性能。尤其是低钠量的锂钠合金负极,添加NaClO_(4)电解液时,活化的柠檬酸钾衍生碳(SCDC-活化)正极在1 A/g电流密度下循环300圈时仍能保持238 mA·h/g的比容量和99%的容量保持率。高钠量的锂钠合金负极,添加锂钠混合离子电解液时,SCDC-活化呈现了319 mA·h/g的比容量,并在循环1040圈时仍能保持93 mA·h/g的高比容量和98%的容量保持率。Compared with single lithium or sodium,lithium-sodium alloy has better performance.In-situ electrochemical preparation of lithium sodium alloy is successfully achieved in button battery which is chargedand discharged under gradient current density by using sodium metal as the positive electrode,lithium metalas the negative electrode,and LiPF_(6),NaClO_(4) or lithium sodium mixed ion electrolyte as the electrolyte.Benefiting from the synergistic effect of lithium and sodium double electrochemically active ions,the lithiumsodium mixed ion capacitors with different lithium contents as negative electrodes show good electrochemicalperformance.In particular,with lithium sodium alloy with high lithium content as the negative electrode and NaClO_(4) electrolyte added,Carbon derived from sodium citrate(Sodium citrate derived carbon,SCDCactivated)maintains the high specific capacity of 238 m A·h/g and the capacity retention rate of 99%at thecurrent density of 1 A/g for 300 cycles.With the addition of lithium-sodium mixed ion electrolyte,SCDCactivated exhibits the specific capacity of 319 m A·h/g,and it can retain 93 m A·h/g and 98%capacityretention rate after 1040 cycles.

关 键 词：锂钠合金 原位电化学制备 锂钠共储特性 

分 类 号：O614.1[理学—无机化学]