Bi2O2S nanosheets anchored on reduced graphene oxides as superior anodes for aqueous rechargeable alkaline batteries

Abstract

To achieve high-performance aqueous rechargeable alkaline batteries (ARABs), durable and high-rate anode materials should be developed. Bi-based materials have always been considered as promising anodes due to their enormous capacity, adequate negative operating voltage range, and three-electron redox characteristics. Nonetheless, the poor kinetics and low cycling stability of bi-based materials have severely limited their applications for ARABs. Here inspired by the unique structural characteristic of two-dimensional (2D) materials with a fast ion diffusion channel and relatively robust structure, 2D/2D Bi2O2S@rGO nanosheets were synthesized using a one-step hydrothermal process as the anode material for ARABs. At a current density of 1 A g−1, the as-optimized anodes exhibit a high specific capacity of 250.51 mAh g−1. Using Bi2O2S@rGO NSs as the anode and (NiCo)9S8 as the cathode, the full cell exhibit a high energy density of 82.91 W h kg−1, a high power density of 7.59 kW kg−1, and excellent cycling stability, with a capacity retention rate of 92.74% after 5,000 cycles. This work could open up a way for environmentally friendly and high-performance anode materials.