水系锌电池中自组装电极-电解质界面相实现高可逆的锌金属负极  

Self-assembled electrode-electrolyte interphase enabling highly reversible Zn metal anode for aqueous zinc batteries

作　　者：沈琪彬 陈泰强 李馨 夏水鑫 袁涛 庞越鹏 郑时有 Qibin Shen;Taiqiang Chen;Xin Li;Shuixin Xia;Tao Yuan;Yuepeng Pang;Shiyou Zheng(School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,China

出　　处：《Science China Materials》2024年第7期2266-2276,共11页中国科学（材料科学）（英文版）

基　　金：supported by the National Natural Science Foundation of China(52271222,51902301 and 22379096);the Natural Science Foundation of Zhejiang Province(LY21E020006);Shanghai Science and Technology Commission(21010503100 and 23DZ1202500)。

摘　　要：由于缺乏先进的固体电解质界面相,水系锌电池的循环寿命受到锌金属负极副反应和枝晶等问题的严重制约.本文介绍了一种由两性分子(APMs)电解液添加剂构建而成的自组装电极-电解质界面相(AEEI).作为一个示范,这里选取聚乙烯吡咯烷酮(PVP)用做APMs,因为它的羰基氧原子与芳香性的吡咯环共轭,从而具有较强的电子给体性质.X射线光电子能谱和傅里叶变换红外光谱分析表明,AEEI的形成和稳定是由APMs的羰基氧原子同时与锌金属和锌离子相互作用推动的.所形成的AEEI主要由富含锌离子的APMs致密层状胶束构成.在电解质中保持APMs的含量在临界聚集浓度(~0.1%)以上,可以保证AEEI的固有稳定性,避免裂纹形成或脱落等问题.得益于其抑制水分解副反应和不利的二维锌扩散的能力,在AEEI的作用下实现了无枝晶的锌沉积.在1 M Zn(OTf)_(2)添加1%PVP的电解液中,形成的AEEI保证了锌对称电池具有超过2000小时的长循环寿命,Zn||Ti电池500个循环后库仑效率高于99.2%,以及V_(2)O_(5)||Zn全电池500个循环后容量的高保持率(达76%).The cycle life of aqueous zinc batteries is hindered by undesired side reactions and dendrite growth of the Zn metal anode due to the lack of an advanced solid electrolyte interphase.Here,a pioneering self-assembled electrode-electrolyte interphase(AEEI)constructed from electrolyte additives of amphiphilic molecules(APMs)is presented.Specifically,polyvinyl pyrrolidone(PVP)molecules are demonstrated due to their high electron-donating property of the carbonyl oxygen atoms in pyrrolidone groups that conjugate with aromatic pyrrole rings.The formation and stability of this interphase is fundamentally prompted by the interaction between the carbonyl oxygen atoms of APMs and Zn metal as well as Zn2+ions,which is elucidated by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy.The resultant AEEI predominantly consists of a dense lamellar micelle of APMs enriched with Zn^(2+)ions.Maintaining the contents of APMs above a critical aggregation concentration of~0.1%within the electrolyte guarantees the inherent stability of the AEEI,avoiding concerns of crack formation or detachment.Conformal and dendrite-free Zn deposition is achieved with the help of the AEEI,benefitting from its ability to suppress water decomposition side reactions and unfavorable 2D diffusion of Zn2+ions.The AEEI ensures a long cycle life of more than 2000 h for symmetric Zn cells,Coulombic efficiency of>99.2%over 500 cycles for Zn||Ti cells,and a capacity retention of 76%over 500 cycles for V_(2)O_(5)||Zn full cells in 1 M Zn(OTf)_(2) electrolyte with 1%PVP.

关 键 词：aqueous zinc batteries zinc metal anode electrode-electrolyte interphase SELF-ASSEMBLY 

分 类 号：TM912[电气工程—电力电子与电力传动] O646[理学—物理化学]