A novel ultrathin single-crystalline Bi 2 O 3 nanosheet wrapped by reduced graphene oxide with improved electron transfer for Li storage

Two-dimensional (2D) metal oxides have been of great interest owning to their particular properties such as rapid electron transfer capability. Herein, we present a novel ultrathin single-crystalline bismuth oxide (Bi2O3) nanosheet wrapped by reduce graphene oxide (rGO), which exhibits rapid electron and Li ion transfer in Li-ion battery anode. The 2D profile of both Bi2O3 and rGO sheets enables them to contact steadily, forming a sandwiched structure, which is beneficial for the transport of electrons and Li ions. The Bi2O3@rGO anodes exhibit a capacity of 218 mAh g−1 after 100 cycles at a rate of 0.5 C, which exceeds the bare Bi2O3 and some reports about Bi2O3 anodes. In addition, density of states (DOSs) and band gap structures of the Bi2O3 wrapped with rGO have been investigated through density functional theory (DFT) calculations, which show that the band gap is improved and the electron transfer is significantly enhanced.