Enhanced electrocatalytic performance of Fe-TiO2/N-doped graphene cathodes for rechargeable Li-O2 batteries

The Fe3+-doped TiO2 on nitrogen-doped graphene (Fe-TiO2/N-doped graphene) electrocatalyst is synthesized and employed as cathode material for Li-O-2 battery. Fe-TiO2 nanoparticles show uniform dispersion on N-doped graphene with less agglomeration compared with TiO2 nanoparticles. The improvement of electrochemical performance of Fe-TiO2/N-doped graphene electrocatalyst is due to the changed electronic and structural properties, which result in forming Ti-O-Fe bonds and oxygen vacancy sites in the crystalline structure of TiO2. The Fe-TiO2/N-doped graphene electrode delivers a discharge capacity of 13,500 mA h g(-1) ((catalytic)) and a cyclic retention of 45 cycles, which are much better compared to the pristine counterpart.