Abstract
Performance, durability, and abundance/cost of electrocatalytic materials are fundamental parameters in for large electrochemical storage solutions like redox-flow batteries (RFB). The acidic environment in Hydrogen–Bromine RFB (HBRFB), which targets tens of thousands of hours in durability, makes the challenge even more acute. Continuous effort to find the most effective and stable catalyst can promote HBRFB goal to become sustainable for high power storage systems. Herein, we explore the lower limits in catalyst loading for the two most active precious group metals (PGMs) – platinum and iridium (individually and in a bimetallic catalyst). The catalyst has been structurally characterized and lab-scale redox-flow cells have been cycled with a decreasing loading of PGM. Carbon support and polymeric coating on Pt catalyst shows a significant increase in the utilization of the catalyst. It enables low platinum loadings (down to 0.36 mgPt/cm2) while maintaining a high discharge power of 0.56 W/cm2 and surface activity (peak power normalization to the electrochemical active area) of 63 W/m2. On the other side, Ir catalyst shows lower discharge power of 0.34 W/cm2, which cannot be improved even at high loading. Finally, bimetallic PtIr reaches a good compromise of high power 0.54 W/cm2 and durability for more than 700 cycles. Each catalyst shows high PGM utilization with discharge power above 1.5 W/mgPGM.
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.