Modulating the interfacial microenvironment via zwitterionic additive for long-cycling aqueous Zn-ion batteries  

两性离子添加剂调控界面微环境实现水系锌离子电池长循环

作　　者：Yawen Xie Shuang Feng Jiechang Gao Tao Cheng Liang Zhang 谢雅雯;冯爽;郜杰昌;程涛;张亮(Institute of Functional Nano&Soft Materials(FUNSOM),Soochow University,Suzhou,215123,China;Jiangsu Key Laboratory of Advanced Negative Carbon Technologies,Soochow University,Suzhou,215123,China)

机构地区：[1]Institute of Functional Nano&Soft Materials(FUNSOM),Soochow University,Suzhou,215123,China [2]Jiangsu Key Laboratory of Advanced Negative Carbon Technologies,Soochow University,Suzhou,215123,China

出　　处：《Science China Materials》2024年第9期2898-2907,共10页中国科学（材料科学）（英文版）

基　　金：supported by the National Natural Science Foundation of China(12275189);Collaborative Innovation Center of Suzhou Nano Science&Technology;the 111 Project;Joint International Research Laboratory of Carbon-Based Functional Materials and Devices。

摘　　要：Aqueous zinc-ion batteries(AZIBs)have garnered extensive attention as promising energy storage systems because of the advantages of low cost and high safety.However,severe parasitic reactions at the Zn anode surface pose a huge challenge for the practical application of AZIBs,especially the intricate hydrogen evolution reaction(HER)and Zn dendrite growth.Herein,zwitterionic taurine with isoelectric point property is introduced as an electrolyte additive to construct a passivation layer by adapting its net charge to the microenvironment variation for stabilizing the Zn anode.The experimental and theoretical results reveal that taurine can not only in-situ form a hydrophobic and zincophilic layer on the Zn anode surface via the chelation with Zn^(2+)in the alkaline interfacial microenvironment,but also buffer the pH change dynamically,thus effectively suppressing the HER and Zn dendrite growth.As a consequence,the taurine-containing electrolyte enables a stable cycling of Zn anodes in symmetric Zn∥Zn cells for more than 1800 h under a deep plating/stripping condition(5 mA cm^(-2)and 5 mAh cm^(-2)).More encouragingly,the full cells coupled with the NH_(4)V_(4)O_(10)cathode can also exhibit an excellent capacity retention of 89.8%after 1200 cycles.This efficient strategy with an environmental adaptive additive offers valuable insights for mitigating the side reactions to achieve practical AZIBs and beyond.水系锌离子电池(AZIBs)作为极具发展前景的储能系统由于具有低成本、高安全性等优点受到了广泛的关注.然而,锌负极表面严重的副反应,特别是复杂的析氢反应(HER)和锌枝晶生长,给AZIBs的实际应用带来了巨大的挑战.本文通过引入具有等电点特性的两性离子牛磺酸,作为电解质添加剂,有效调节其净电荷以适应微环境的变化来构建钝化层从而稳定锌负极.实验和理论结果表明,牛磺酸在碱性界面微环境中能够与Zn^(2+)发生螯合作用并在锌负极表面原位形成疏水且亲锌的钝化层,同时动态缓冲pH值的变化,从而抑制了HER和枝晶生长.因此,在含牛磺酸添加剂的电解液中,Zn‖Zn对称电池可以稳定循环1800小时以上(5mA cm^(-2)和5 mAh cm^(-2)).此外,采用NH_(4)V_(4)O_(10)正极和锌负极的全电池在1200次循环后也具有高达89.8%的优异容量保持率.这种可以良好适应微环境的添加剂为减轻电池副反应,从而实现高性能水系锌离子电池的实际应用提供了新的思路.

关 键 词：aqueous zinc-ion batteries passivation layer pH buffer interfacial microenvironment zwitterionic additive 

分 类 号：TM912[电气工程—电力电子与电力传动]