基于有机溶剂原位制备的致密疏水铜金属层在保护锌负极中的应用  

Application of a densely hydrophobic copper metal layer in-situ prepared with organic solvents for protecting zinc anodes

作　　者：罗秋洋 唐晓宁[1] 夏澍 刘珺楠 杨兴富 雷杰 LUO Qiuyang;TANG Xiaoning;XIA Shu;LIU Junnan;YANG Xingfu;LEI Jie(School of Materials and Metallurgy,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学材料与冶金学院,贵阳550025

出　　处：《无机化学学报》2024年第7期1243-1253,共11页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.22065005);贵州省基础研究(自然科学)项目(黔科合基础-ZK[2023]一般048);贵州大学引进人才科研项目(No.202052)资助。

摘　　要：通过在N-甲基吡咯烷酮(NMP)有机溶剂中锌电极与CuI之间的置换反应,在锌电极上原位构建了一层致密且疏水的铜金属保护层(Cu@Zn)。铜金属保护层能有效地隔离锌电极与电解液的接触,减少锌电极-电解液界面的析氢和腐蚀等副反应。同时,铜金属保护层还具有较好的亲锌性,更小的界面电阻,更低的成核能垒,有利于锌离子均匀沉积,从而有效抑制了锌枝晶的生成。Cu@Zn对称电池实现了超过1 700 h(1 mA·cm^(-2))和1 330 h(3 mA·cm^(-2))的循环寿命。采用商用MnO_(2)与之匹配得到的Cu@Zn||MnO_(2)全电池不仅在1 A·g^(-1)下具有168.5 mAh·g^(-1)的可逆比容量,还可稳定循环2 000次以上。Herein,a dense and hydrophobic Cu metal protective layer was constructed in-situ on the Zn electrode(Cu@Zn) through a displacement reaction in an organic solvent.Specifically,CuI powder was dissolved in methyl-2-pyrrolidone(NMP) and stirred for 12 h to obtain a uniform solution.Subsequently,the bare Zn was immersed in the solution at 80 ℃ for 6 h,and then washed with absolute ethanol three times to achieve the Cu@Zn electrode.Scanning electron microscopy(SEM) and X-ray diffraction(XRD) analyses confirm a dense Cu protective layer on the surface of the Cu@Zn electrode.Additionally,the better hydrophobicity of the Cu@Zn electrode was demonstrated through contact angle measurements with a 2 mol·L^(-1) ZnSO_(4) electrolyte.The dense and hydrophobic Cu metal protective layer can effectively isolate the direct contact between the Zn electrode and electrolyte,suppressing side reactions such as hydrogen evolution and corrosion at the electrode/electrolyte interface.Furthermore,the Cu layer possesses zincophilicity,reduced interfacial resistance,and a lower nucleation energy barrier,thereby promoting uniform Zn deposition and effectively inhibiting dendritic growth.As a result,Cu@Zn symmetric cells exhibited continuous stable performance for 1 700 and 1 330 h at 1 mA·cm^(-2),1 mAh·cm^(-2) and 3 mA·cm^(-2),1 mAh·cm^(-2),respectively,which were higher than those of bare Zn symmetric cells(204 and 120 h).Furthermore,the Cu@Zn‖MnO_(2full) cell delivered a specific capacity of 168.5 mAh·g^(-1) at 1 A·g^(-1) respectively,maintaining stability for over 2 000cycles.

关 键 词：水系锌离子电池 锌电极 致密疏水 亲锌性 铜金属层 

分 类 号：O614.121[理学—无机化学] TM912[理学—化学] TB34[电气工程—电力电子与电力传动]