摘要
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.
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)
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)。
