Free-standing flexible graphene oxide paper electrode for rechargeable Li–O2 batteries

Abstract

A smooth, free-standing and flexible graphene oxide paper was produced using a vacuum filtration technique. This graphene oxide paper was characterized by scanning electron microscopy, X-ray diffraction and Raman spectroscopy techniques. The charge–discharge characteristics of the graphene oxide paper have been investigated from 1 V to 4.5 V at a constant 0.01 mA cm−2 with an ECC–Air test cell. The electrochemical impedance of the graphene oxide paper has been measured to investigate the difference in the resistance of the cell before and after an electrochemical cycling test. The Li–air cell with a graphene oxide flexible paper cathode exhibited a 612 mAh g−1 discharge capacity and a 555 mAh g−1 charge capacity after 10 cycles. This study demonstrated that graphene oxide paper might be a good alternative cathode material for Li–O2 batteries in the future.