Reduced graphene oxide decorated with Bi₂O_2.33 nanodots for superior lithium storage

Bismuth oxides are important battery materials owing to their ability to electrochemically react and alloy with Li, which results in a high capacity level, which substantially exceeds that of graphite anodes. However, this high Li-storage capability is often compromised by the poor electrochemical cyclability and rate capability of bismuth oxides. To address these challenges, in this study, we design a hybrid architecture composed of reduced graphene oxide (rGO) nanosheets decorated with ultrafine Bi₂O_2.33 nanodots (denoted as Bi₂O_2.33/rGO), based on the selective and controlled hydrolysis of a Bi precursor on graphene oxide and subsequent crystallization via solvothermal treatment. Because of its high conductivity, large accessible area, and inherent flexibility, the Bi₂O_2.33/rGO hybrid exhibits stable and robust Li storage (346 mA·h·g^-1 over 600 cycles at 10 C), significantly outperforming previously reported Bi-based materials. This superb performance indicates that decorating rGO nanosheets with ultrafine nanodots may introduce new possibilities for the development of stable and robust metal-oxide electrodes.