Due to their layered structure and high theoretical capacity, bismuth chalcogenides have been proposed as anodes in organic electrolyte Li- and Na-ion batteries. On the other hand, their electrochemical properties in aqueous systems have not been reported. Here, the electrochemical performance of Bi2Se3 thin films in 1 M NaNO3 aqueous electrolyte is presented. This aqueous Bi2Se3 system was found to have up to two orders of magnitude increased diffusion coefficients, compared to other anode materials in Na electrolyte-based systems, as well as limited anode electrode degradation over 5 CVs and significant changes in the anode after 30 CVs.
