An aqueous magnesium-ion hybrid supercapacitor operated at-50℃  

作　　者：Guoshen Yang Gangrui Qu Chi Fang Jie Deng Xianqi Xu Yinghao Xie Tian Sun Yachao Zhu Jiaxin Zheng Hang Zhou 

机构地区：[1]School of Electronic and Computer Engineering,Peking University Shenzhen Graduate School,Shenzhen,518055,China [2]School of Advanced Materials,Peking University Shenzhen Graduate School,Shenzhen,China [3]College of Food and Biological Engineering,Chengdu University,Chengdu,610106,China [4]Institute Charles Gerhardt Montpellier,UMR 5253,Universitae Montpellier,Montpellier,CC 1502,France

出　　处：《Green Energy & Environment》2024年第4期702-712,共11页绿色能源与环境（英文版）

基　　金：supported by Shenzhen Science and Technology Innovation Committee(Nos.JCYJ20190806145609284,GJHZ20190820091203667,JSGG20201102161000002,SGD-X20201103095607022);Guangdong Basic and Applied Basic Research Foundation(2020A1515010716);Guangdong Introducing Innovative and Entrepreneurial Teams Program(2019ZT08Z656);P.H.would like to acknowledge Shenzhen Science and Technology Program(KQTD20190929172522-248).

摘　　要：The recent advances in aqueous magnesium-ion hybrid supercapacitor(MHSC)have attracted great attention as it brings together the benefits of high energy density,high power density,and synchronously addresses cost and safety issues.However,the freeze of aqueous electrolytes discourages aqueous MHSC from operating at low-temperature conditions.Here,a low-concentration aqueous solution of 4 mol L^(-1) Mg(ClO_(4))_(2) is devised for its low freezing point(-67℃)and ultra-high ionic conductivity(3.37 mS cm^(-1) at-50℃).Both physical characterizations and computational simulations revealed that the Mg(ClO_(4))_(2) can effectively disrupt the original hydrogen bond network among water molecules via transmuting the electrolyte structure,thus yielding a low freezing point.Thus,the Mg(ClO_(4))_(2) electrolytes endue aqueous MHSC with a wider temperature operation range(-50℃–25℃)and a higher energy density of 103.9 Wh kg^(-1) at 3.68 kW kg^(-1) over commonly used magnesium salts(i.e.,MgSO_(4) and Mg(NO_(3))_(2))electrolytes.Furthermore,a quasi-solid-state MHSC based on polyacrylamide-based hydrogel electrolyte holds superior low-temperature performance,excellentflexibility,and high safety.This work pioneers a convenient,cheap,and eco-friendly tactic to procure low-temperature aqueous magnesium-ion energy storage device.

关 键 词：Low-concentration aqueous electrolyte Anti-freezing property Magnesium-ion hybrid supercapacitor High energy density 

分 类 号：TM53[电气工程—电器]