Graphite as a positive electrode material of dual ion batteries(DIBs)has attracted tremendous attentions for its advantages including low lost,high working voltage and high energy density.However,very few literatures ...Graphite as a positive electrode material of dual ion batteries(DIBs)has attracted tremendous attentions for its advantages including low lost,high working voltage and high energy density.However,very few literatures regarding to the real-time observation of anion intercalation behavior and surface evolution of graphite in DIBs have been reported.Herein,we use in situ atomic force microscope(AFM)to directly observe the intercalation/de-intercalation processes of PF6^-in graphite in real time.First,by measuring the change in the distance between graphene layers during intercalation,we found that PF6^-intercalates in one of every three graphite layers and the intercalation speed is measured to be 2μm-min^-1.Second,graphite will wrinke and suffer structural damnages at high voltages,along with severe electrolyte decomposition on the surface.These findings provide useful information for further optimizing the capacity and the stability of graphite anode in DIBs.展开更多
基金This research was financially supported by Soft Science Research Project of Guangdong Province(No.2017B030301013)the Shenzhen Science and Technology Research(Nos.CYJ20170818085823773 and ZDSYS201707281026184).
文摘Graphite as a positive electrode material of dual ion batteries(DIBs)has attracted tremendous attentions for its advantages including low lost,high working voltage and high energy density.However,very few literatures regarding to the real-time observation of anion intercalation behavior and surface evolution of graphite in DIBs have been reported.Herein,we use in situ atomic force microscope(AFM)to directly observe the intercalation/de-intercalation processes of PF6^-in graphite in real time.First,by measuring the change in the distance between graphene layers during intercalation,we found that PF6^-intercalates in one of every three graphite layers and the intercalation speed is measured to be 2μm-min^-1.Second,graphite will wrinke and suffer structural damnages at high voltages,along with severe electrolyte decomposition on the surface.These findings provide useful information for further optimizing the capacity and the stability of graphite anode in DIBs.