Chemical Bonding Construction of Reduced Graphene Oxide-Anchored Few-Layer Bismuth Oxychloride for Synergistically Improving Sodium-Ion Storage

Two-dimensional-layered materials (TDLMs) have gained enormous attention because of their open layered structures and high specific capacities in sodium ion batteries (SIBs). However, effectively suppressing the fast capacity fading and serious volume change in cycling process is still a challenge. Herein, we report reduced graphene oxide-riveted bismuth oxychloride (BiOCl) by inducing interfacial Bi–C bonding as the high-performance anode for SIBs. This new composite structure can deliver an initial charge capacity of 266.6 mA h g–1 at 50 mA g–1 and a cycling stability maintaining 81.7% after 100 cycles, which is much superior to recent data of metal oxyhalide. The excellent charge/discharge cyclability is associated with the strong interfacial coupling that significantly reinforces charge transfer and structural stability of the electrode. At the same time, the remarkable mechanical stretching could mitigate the volume expansion and hence maintain the integrity of BiOCl nanosheets during cycling. The proposed strategy based on constructing strong interfacial coupling through chemical bonding and interlayer engineering may hold great promise for developing TDLMs for next-generation rechargeable batteries.