Abstract
Polysulfide is a promising redox couple employed in various aqueous redox flow batteries (RFB) for large scale electrochemical energy storage due to its high solubility and low cost. However, polysulfide has much lower rate constant in comparison with other commonly used redox couples in RFB. Therefore, efficient electrocatalysis is a key to achieving high performance for polysulfide-based RFB. Here we first systematically investigated the electrocatalytic activity of various pyrite phase metal disulfides (FeS2, CoS2, NiS2) as thin film electrodes towards polysulfide redox reactions under steady state condition. Then we further demonstrated a high-performance polysulfide/ferrocyanide RFB using optimized high surface area NiS2 nanostructures grown on carbon paper as the electrode. The NiS2/carbon paper electrode was able to achieve a high current density of 38.6 mA cm-2 at an over potential of 100 mV. An aqueous polysulfide/ferrocyanide RFB employing NiS2/carbon paper as anode and plain carbon paper as cathode was further evaluated by constant current cycling test and electrochemical impedance spectroscopy to demonstrate high charging-discharging cycling performance and low charge transfer impedance.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.