Metallic zinc is an excellent anode material for Zn-ion batteries,but the growth of Zn dendrite severely hinders its practical application.Herein,an efficient and economical cationic additive,poly dimethyl diallyl amm...Metallic zinc is an excellent anode material for Zn-ion batteries,but the growth of Zn dendrite severely hinders its practical application.Herein,an efficient and economical cationic additive,poly dimethyl diallyl ammonium(PDDA) was reported,used in aqueous Zn-ion batteries electrolyte for stabilizing Zn anode.The growth of zinc dendrites can be significantly restrained by benefiting from the pronounced electrostatic shielding effect from PDDA on the Zn metal surface.Moreover,the PDDA is preferentially absorbed on Zn(002) plane,thus preventing unwanted side reactions on Zn anode.Owing to the introduction of a certain amount of PDDA additive into the common ZnSO_(4)-based electrolyte,the cycle life of assembled Zn‖Zn cells(1 mA·cm^(-2) and 1 mAh·cm^(-2)) is prolonged to more than 1100 h.In response to the perforation issue of Zn electrodes caused by PDDA additives,the problem can be solved by combining foamy copper with zinc foil.For real application,Zn-ion hybrid supercapacitors and MnO_(2)‖Zn cells were assembled,which exhibited excellent cycling stability with PDDA additives.This work provides a new solution and perspective to cope with the dendrite growth problem of Zn anode.展开更多
Graphene oxide(GO),an important chemical precursor of graphene,can stably disperse in aqueous surrounding and undergo aggregation as metal cations introduced.The usual instability of GO with ions is caused by the shie...Graphene oxide(GO),an important chemical precursor of graphene,can stably disperse in aqueous surrounding and undergo aggregation as metal cations introduced.The usual instability of GO with ions is caused by the shielding effect of ions and crosslinking between GO and ions.However,the dynamic stability of GO under ions exchange still remains unclear.Here,we investigated the dynamic dispersion stability of GO with metal ions and observed a redispersion behavior in concentrated Fe3+solution,other than permanent aggregation.The exchange with Fe3+ions drives the reversion of zeta(ζ)potential and enables the redispersion to individual GO-Fe3+complex sheets,following a dynamic electric double layer(EDL)mechanism.It is found that the specifically strong electrostatic shielding effect and coordination attraction between Fe3+and functional oxygen groups allows the selective redispersion of GO in concentrated Fe3+solution.The revealed dynamic dispersion stability complements our understanding on the dispersive stability of GO and can be utilized to fabricate graphene-metal hybrids for rich applications.展开更多
基金financially supported by Fuzhou science and technology project (Nos.2021-ZD-213 and 2020-Z-6)Fujian Provincial Department of Science and Technology(Nos.2021T3036,2020T3004,2020T3030 and 2020H0040)+2 种基金STS Science And Technology Project of the Chinese Academy of Sciences(No.KFJ-STS-QYZD-2021-09-001)Quanzhou Science and Technology Project (No.2020G17)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy (No.2021009)。
文摘Metallic zinc is an excellent anode material for Zn-ion batteries,but the growth of Zn dendrite severely hinders its practical application.Herein,an efficient and economical cationic additive,poly dimethyl diallyl ammonium(PDDA) was reported,used in aqueous Zn-ion batteries electrolyte for stabilizing Zn anode.The growth of zinc dendrites can be significantly restrained by benefiting from the pronounced electrostatic shielding effect from PDDA on the Zn metal surface.Moreover,the PDDA is preferentially absorbed on Zn(002) plane,thus preventing unwanted side reactions on Zn anode.Owing to the introduction of a certain amount of PDDA additive into the common ZnSO_(4)-based electrolyte,the cycle life of assembled Zn‖Zn cells(1 mA·cm^(-2) and 1 mAh·cm^(-2)) is prolonged to more than 1100 h.In response to the perforation issue of Zn electrodes caused by PDDA additives,the problem can be solved by combining foamy copper with zinc foil.For real application,Zn-ion hybrid supercapacitors and MnO_(2)‖Zn cells were assembled,which exhibited excellent cycling stability with PDDA additives.This work provides a new solution and perspective to cope with the dendrite growth problem of Zn anode.
基金supported by the National Natural Science Foundation of China(Nos.51533008,51603183,51703194,51803177,21805242 and 5197030056)National Key R&D Program of China(No.2016YFA0200200)+4 种基金Fujian Provincial Science and Technology Major Projects(No.2018HZ0001-2)Hundred Talents Program of Zhejiang University(No.188020*194231701/113)Key Research and Development Plan of Zhejiang Province(No.2018C01049)the Fundamental Research Funds for the Central Universities(Nos.2017QNA4036,2017XZZX001-04)Foundation of National Key Laboratory on Electromagnetic Environment Effects(No.614220504030717)。
文摘Graphene oxide(GO),an important chemical precursor of graphene,can stably disperse in aqueous surrounding and undergo aggregation as metal cations introduced.The usual instability of GO with ions is caused by the shielding effect of ions and crosslinking between GO and ions.However,the dynamic stability of GO under ions exchange still remains unclear.Here,we investigated the dynamic dispersion stability of GO with metal ions and observed a redispersion behavior in concentrated Fe3+solution,other than permanent aggregation.The exchange with Fe3+ions drives the reversion of zeta(ζ)potential and enables the redispersion to individual GO-Fe3+complex sheets,following a dynamic electric double layer(EDL)mechanism.It is found that the specifically strong electrostatic shielding effect and coordination attraction between Fe3+and functional oxygen groups allows the selective redispersion of GO in concentrated Fe3+solution.The revealed dynamic dispersion stability complements our understanding on the dispersive stability of GO and can be utilized to fabricate graphene-metal hybrids for rich applications.
